Where your numbers come from.
Every result in this app is measured against a range, rolled into a score, and read against your own baseline. This page explains each of those steps, names the evidence behind every Prime range, and defines the words the app uses. It is written to be checked: every source is linked, and a range with no source yet says so.
1. Three ranges, and which one you see
A lab range answers “is this abnormal?”. A Prime range answers “where should I aim?”. They are different questions, and a result can be normal by the first and outside the second at the same time.
There are three ranges a marker can be read against, and they come from different places.
| Range | It answers | It comes from |
|---|---|---|
| Population percentile | Where do people like me actually sit? | National survey data (NHANES), which samples everyone, healthy or not |
| Lab reference range | Is this result abnormal? | The laboratory that ran your sample, from a screened healthy group, on its own instrument |
| Prime range | Where should I aim? | Prime Years, from published evidence, by the method in the next section |
Only the third is a target. The first two describe; the third prescribes. They can sit far apart. HDL cholesterol is the clearest example on this page: a laboratory range has no ceiling, because a high HDL was long read as good, and the Copenhagen cohorts cited in the table below found mortality rising again at the highest values. A person at the top of the lab’s range is “completely normal” and outside the Prime range at once.
Which range you see beside a result
When your lab report carries its own reference range, that is the one shown beside the result, and the verdict on the results page is measured against it. When a report carries several ranges and does not say which applies to you, none is shown rather than a guess. The lab’s range is matched to the instrument that ran your sample on the day it ran, which is stronger than any static table. Your Prime range is still recorded on every result, and it is what the Prime Score and the marker charts are measured against. Substituting one for the other would quietly change the claim being made, so the app keeps both and says which is which.
2. How a Prime range is set
A Prime range is set from the strongest evidence that exists for that marker, on a ladder of five evidence tiers, with a sixth label for a marker that has none. Every marker below carries its own entry: the step a range came from and what it cites, or, where that is still missing, which of the two is missing and why. Nothing is left blank for you to interpret.
112 separate judgments made without a rule would be 112 different rules, and you are entitled to assume that “in range” means the same thing for every marker on one screen. So there is one rule. A range is set from the highest tier that has evidence for that marker; lower tiers are not consulted once a higher one applies — and where no tier has evidence we defensibly believe, the judgment is to set no range, which is why 88 of the 112 carry none.
- Tier 1. Guideline threshold. A guideline body has set a target from hard outcomes such as heart attacks or kidney failure. The threshold is the zone boundary, unchanged.
- Tier 2. Risk inflection in cohort data. Published cohort data show where risk is lowest. The zone is that low point, not the whole span below a cut-off.
- Tier 3. Functional sufficiency. A level at which a body function stops failing or saturates. The zone starts at that level, and still needs a ceiling.
- Tier 4. Healthy-cohort reference interval, narrowed. No outcome evidence exists, but a properly screened healthy cohort has a published reference interval. The zone is drawn inside it, toward the end that is better for that marker.
- Tier 5. Population percentile, narrowed. Only population survey data exist. The zone is drawn inside the distribution, and is labelled as the weakest evidence tier.
- Tier 6. Reported, not evidence-tiered. The marker is shown with context and no evidence tier, usually because it is a device maker’s own composite score.
The rules every range must satisfy
- Never looser than a guideline threshold. If a guideline says under 70 and the range says under 100, the range is wrong.
- Never narrower than the test can measure. A range tighter than the assay’s own variation is scoring noise.
- Never applied across methods where the method sets the scale. Free testosterone by equilibrium dialysis reads about ten times a direct immunoassay. A range must name its method.
- Never stretched beyond the studied population. A range inherits the population its source measured.
- Every range records its tier and its source. A range whose tier cannot be named is not ready.
- Sufficiency is not a target to exceed. A level that is enough is a floor, not an invitation to go higher.
- Where the Prime range and the lab range barely overlap, the page must say so. You are being told two contradictory-sounding things at once, and that deserves a sentence, not a footnote.
What is not copied from anyone else
Some longevity programs publish tight “optimal” targets described as the levels of a healthy young adult, with no citation, reference population or method behind them. That description does not survive contact with data: on the national survey cited in the table below, the average young adult already sits outside several of the Prime ranges. Young is not the same as healthy. An unauditable target is exactly what this page exists to avoid.
3. How a result is scored
Inside your Prime range a result scores 100. Outside it, the score falls in a straight line with distance. The same rule scores every marker, whichever direction is good for it.
Each result gets a score from 0 to 100 for how close it sits to the Prime range. Inside the range, 100. Just outside either edge, 85. From there the score falls in a straight line, reaching 0 at 1.5 range-widths beyond the edge. The rule is symmetric, so “lower is better” and “higher is better” are properties of the range, not of the scorer: a lower-is-better marker such as hs-CRP simply has no clinical floor, and the chart draws no “below” band for it.
The score is shown as one of three words.
- Optimal: a score of 85 or more. Inside the range, or at its edge.
- Watch: a score from 60 to 84. Outside the range, but not far.
- Attention: a score under 60. Well outside the range.
Every dot on a marker chart is scored the same way, and each one is scored against the Prime range recorded on that sample when it was taken. A range tightened on a later panel does not recolor your history, and the chart says so in words when it applies.
4. The Prime Score and biological age
The Prime Score is the average of your marker scores, with wearable readings capped at 25% of it. Biological age is a simple estimate derived from that score, and it is provisional.
The Prime Score
Your Prime Score is the weighted average of every marker that has a reading. Blood markers and wearable markers are not equally strong signals: a poor night’s HRV is noise where an out-of-range HbA1c is signal, and a wearable reports every day while a blood panel arrives a few times a year. So the wearable group as a whole is capped at 25% of the score, however few blood markers there are. Below that cap nothing is re-weighted. The score is not computed at all until you have a blood panel; a wearable alone is not a whole-health number, and the app says so rather than printing one.
The score is recomputed once a day. A day on which nothing behind it changed adds no point, so the chart holds one point for each day the score was seen to move.
Biological age
The biological age shown is derived from your Prime Score by a deliberately simple model: a score of 72 reads as your calendar age, and every 2.3 points above or below it moves the estimate one year younger or older. It has a single anchor point, it is not an epigenetic clock, and it declines to answer outside ages 20 to 120 rather than print a number nothing stands behind. Treat it as a motivating summary of your marker scores, not as a measurement.
5. How a therapy is judged
A therapy is judged against your own baseline, on the markers it is meant to move, while the markers it could disturb are watched. Nobody is compared with an average.
Each therapy Prime Years offers is tied to the markers it is meant to move (its targets) and the markers it could push the wrong way (its safety markers). That mapping is the same for everyone. What is yours is the comparison: each target’s latest reading against the reading you started with. This is the N-of-1 method, the same before-and-after logic a clinician uses, applied to your record automatically.
- Too early to tell: fewer than six weeks since the therapy started. Most markers have not had time to move.
- Working: every target has moved at least 5% in its good direction, and at least one is Optimal.
- Partial response: at least one target has moved at least 5% in its good direction, but not every target has, or none has reached Optimal yet.
- No response yet: no target has moved 5% in its good direction since baseline. Worth reviewing with your provider.
- No results yet: none of the therapy’s targets has a reading. The app says this rather than guessing.
A verdict is only ever written for a therapy actually recorded on your chart. The app never assumes you are on something because a marker happens to look like it.
6. What this page does not claim
Prime ranges, the Prime Score and the biological-age model are decision-support tools. They are not a diagnosis and do not replace your provider’s judgment.
- Every Prime range is a proposal awaiting clinical sign-off. The ranges were drafted by the team building this app from the evidence in section 7, using the method in section 2. They are under clinical review and will change as that review lands. This page is updated when they do.
- The app tracks 112 markers and sets a Prime range for 24 of them. 19 of those 24 have a verified source attached today. 2 are device composites reported without a tier. The 3 still under review are marked below, with a sentence saying what is missing. A range without a source is not hidden behind a borrowed citation. The other 88 markers are tracked with no Prime range at all — shown below as “Tracked, no PYM target”. That is a finding, not a review still outstanding: we looked and did not find a target we could defend, so the app records the reading and does not score it.
- Almost no range is split by sex or age. PSA is the exception: its range widens with age, and the bands are shown against it in the table. No marker currently carries a separate range for women. Every other range applies to everyone, and the note beside a marker says when that matters. Where your lab report carries its own range, that one is matched to you and is the one shown beside the result.
- Nothing here is a claim of treatment effect. Whether a therapy works for you is judged from your own readings, after the fact, by the method in section 5.
7. Sources, marker by marker
Every marker the app tracks — its Prime range where it has one, the evidence tier that range came from, and the sources it cites. “Under review” means a range exists but no verified source is attached yet, and the note says why. “No target found” means there is no Prime range to support.
Hormones
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Free testosterone | Tracked, no PYM target | No target found | The shipped 150 to 250 pg/mL band scored a healthy-men reference interval (equilibrium dialysis) as a therapeutic target, which describes who is healthy rather than where TRT should aim. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement; TRT is judged on no scored target until one is sourced. Equilibrium dialysis matters: a direct immunoassay reads roughly a tenth of this for the same blood. No source, because there is no target to support. |
| Total testosterone | Tracked, no PYM target | No target found | The shipped 500 to 900 ng/dL band was a reference interval for healthy men — where most people fall — scored as though it were a therapeutic target, which is a different claim the reference study never makes. Pulled on 2026-09-15 with no replacement rather than kept as a forced fit; TRT is judged on no scored target until one is sourced. No source, because there is no target to support. |
| IGF-1 | 120 to 160 ng/mL | Tier 2 Risk inflection in cohort data | Set on the range associated with the lowest all-cause mortality in a meta-analysis of 19 prospective cohorts covering 30,876 people. The relationship is U-shaped: compared with the middle of the distribution, low IGF-1 carries a 33% higher risk of death and high IGF-1 a 23% higher risk, so this is a band to stay inside rather than a number to push up. It is also the safety marker for the recovery peptide protocol, because sermorelin and ipamorelin raise IGF-1 by design. Note that the range sits below the population: the reference median for men in their forties is around 199 ng/mL. Sources: Rahmani 2022, Kim 2020 |
| PSA | Under 2.5 ng/mL 18–49: under 2.5 ng/mL 50–59: under 3.5 ng/mL 60–69: under 4.5 ng/mL 70–+: under 6.5 ng/mL | Tier 1 Guideline threshold | A screening ceiling, not a wellness target. Oesterling 1993 established the age-specific ninety-fifth percentiles that are standard in prostate screening — from 471 community men screened cancer-free by biopsy and ultrasound — at 2.5 ng/mL to age 49, 3.5 through the fifties, 4.5 through the sixties and 6.5 beyond. The prostate enlarges with age, so unlike most markers here the threshold genuinely belongs to the age rather than describing it. The trend matters more than any single value. Sources: Oesterling 1993, Morgan 1996 |
| Free PSA % | 25 to 100% | Tier 1 Guideline threshold | A validated decision threshold, not an interval. Across 773 men at seven US medical centres, a free-PSA share at or below 25 percent was the point at which biopsy was recommended: it caught 95 percent of cancers while sparing a fifth of the biopsies that would otherwise have been done. Higher is better, so the zone is 25 percent and above. The scope is narrow and it matters — the figure was derived in men aged 50 to 75 whose total PSA sat between 4 and 10 ng/mL and whose prostate felt normal on examination. Outside that window this is not the test that was validated, and a reassuring percentage does not carry the meaning it carries inside it. Sources: Catalona 1998 |
| Free T3 | Tracked, no PYM target | No target found | Studies of free T3 within the normal range against hard outcomes conflict and several are null, and the largest pooled analyses of thyroid function and mortality did not include it. Free T3 also falls in any serious non-thyroidal illness, so a low value is often a report on general health rather than on the thyroid. Reported without a target. No source, because there is no target to support. |
| Total T3 | Tracked, no PYM target | No target found | Outcome research in thyroid disease is written against TSH and free T4, not total T3, and the total moves with carrier-protein levels that change in pregnancy, with oestrogen and in liver disease. No published target exists for a healthy adult. No source, because there is no target to support. |
| Total T4 | Tracked, no PYM target | No target found | The same problem as total T3: carrier proteins dominate the number, and the outcome literature targets free T4 and TSH. Converting a free T4 target into a total T4 one is not a conversion the biology allows. Reported without a target. No source, because there is no target to support. |
| TPO antibodies | Tracked, no PYM target | No target found | This is a positive-or-negative test read against whatever upper limit the performing assay declares, and those limits differ severalfold between methods. PYM stamps one zone onto every laboratory’s result, so an assay-specific cut-off cannot be that zone. What the antibody tells a clinician is presence, not level. No source, because there is no target to support. |
| Thyroglobulin antibodies | Tracked, no PYM target | No target found | Assay-specific like TPO antibodies, and read as present or absent. Their main clinical job is to flag that a thyroglobulin result cannot be trusted, which is a fact about another test rather than a target of its own. No source, because there is no target to support. |
| Thyroglobulin | Tracked, no PYM target | No target found | A tumour marker, interpreted against a fixed assay and a member’s own previous value after thyroid surgery, not against a population target. In somebody with an intact thyroid it reflects gland size and activity, and no guideline sets a level to aim for. No source, because there is no target to support. |
| DHEA-S | Tracked, no PYM target | No target found | The Endocrine Society advises against routine DHEA measurement and supplementation outside adrenal insufficiency, so the body that would set a target explicitly declines to. The cohort data showing a U-shape come from frail older populations, where the finding is about illness rather than about a level to aim at. Reported without a target. No source, because there is no target to support. |
| Estrone | Tracked, no PYM target | No target found | Cardiovascular mortality studies in postmenopausal women found no association with estrone, and the thresholds proposed in high-risk cardiac cohorts have not held up. Its level also depends on body fat, which is where most postmenopausal oestrogen is made, so the number reports adiposity as much as endocrine state. No source, because there is no target to support. |
| Progesterone | Tracked, no PYM target | No target found | A value means nothing without the cycle day it was drawn on, and after menopause it is low in everybody. Menopause guidance is explicit that serum hormone levels rarely guide hormone therapy, which is decided on symptoms. Reported without a target. No source, because there is no target to support. |
| FSH | Tracked, no PYM target | No target found | FSH is a staging and diagnostic test: it says where somebody is in the menopause transition, or whether a low testosterone comes from the testes or the pituitary. Neither use has a level to aim for, and in perimenopause it swings widely between draws. No source, because there is no target to support. |
| LH | Tracked, no PYM target | No target found | Its clinical job is to classify a low testosterone as coming from the testes or from the pituitary, which is a diagnostic fork rather than a target. The testosterone guideline that defines that use sets no LH level to aim for. No source, because there is no target to support. |
| AMH | Tracked, no PYM target | No target found | A fertility and ovarian-reserve test, used to predict response to ovarian stimulation rather than health. Reproductive medicine guidance is clear that it predicts egg yield better than it predicts the chance of conceiving, and it has no longevity target at all. No source, because there is no target to support. |
| Prolactin | Tracked, no PYM target | No target found | The endocrine guideline for high prolactin defines the diagnosis against each laboratory’s own upper limit rather than a single number, so there is no shared threshold to ship. A single high value also often reflects the draw itself — stress, or a needle that took two attempts — and is confirmed by repeating it rather than acted on. No source, because there is no target to support. |
| SHBG | Tracked, no PYM target | No target found | The shipped 20 to 60 nmol/L band (30 to 110 for women) scored the centre of a common laboratory interval, not yet even split by age, as a therapeutic target with no citation attached. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Estradiol | Tracked, no PYM target | No target found | The shipped 20 to 40 pg/mL band scored a target the Endocrine Society guideline names no threshold for, at levels standard immunoassays measure imprecisely, with no citation attached. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Cortisol (morning) | Tracked, no PYM target | No target found | The shipped 8 to 18 µg/dL band scored the middle of a healthy-cohort reference interval, drawn from a morning mass-spectrometry sample, as a wellness target; an afternoon or saliva result is a different test entirely. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Hematocrit | Under 54% | Tier 1 Guideline threshold | A testosterone-therapy safety ceiling, not a wellness target. The Endocrine Society clinical practice guideline directs stopping or reducing testosterone therapy if hematocrit climbs above 54%, and the zone is that stop threshold, ceiling only. Sources: Bhasin 2018 |
| TSH | Tracked, no PYM target | No target found | The shipped 1.0 to 2.5 mIU/L band scored the centre of a disease-free reference population's distribution (NHANES III) as a therapeutic target, which the reference study never claims to be. A result between 2.5 and 4 is not a thyroid diagnosis. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Free T4 | Tracked, no PYM target | No target found | The shipped 1.0 to 1.6 ng/dL band scored a target with no method attached — free T4 reference intervals are set per assay by each laboratory, and no citation named which assay this band was drawn from. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
Metabolic
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Uric acid | Tracked, no PYM target | No target found | Chen 2025 (NHANES 1999-2018) gives three separate risk-curve inflection points — 5.40, 5.75 and 5.94 mg/dL against three different outcomes — not a floor-and-ceiling band. The shipped 3.5 to 5.5 mg/dL zone stitched an unrelated antioxidant-role floor onto the lowest inflection and scored members against the span between, which the paper does not support. Pulled on 2026-09-15 with no replacement. No source, because there is no target to support. |
| Amylase | Tracked, no PYM target | No target found | The shipped 50 to 95 U/L band scored the middle half of a multi-country healthy-cohort reference interval as a wellness target; an isolated high amylase is most often a harmless immunoglobulin complex rather than anything pancreatic. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Lipase | Tracked, no PYM target | No target found | The shipped 28 to 55 U/L band scored the middle half of a single-platform reference interval as a wellness target, on a marker whose two standard estimation methods disagree by 23 percent at the upper limit. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Selenium | 120 to 150 µg/L | Tier 3 Functional sufficiency | The only zone here whose two ends come from different kinds of evidence, and they agree. The floor is functional: in a randomised, placebo-controlled trial in 119 UK adults aged 50 to 64, the supplement dose that fully expressed selenoprotein P raised plasma selenium from 96 to 118 ng/mL, so below roughly 120 the body is still short of what its selenium-dependent enzymes need. The ceiling is a risk curve: across 13,887 US adults followed twelve years, mortality fell as selenium rose to about 130 ng/mL and then turned upward again above 150. More is not better with this one, which is unusual for a nutrient. Micrograms per litre and nanograms per millilitre are the same quantity written two ways, so both studies sit on this scale without conversion. Sources: Hurst 2010, Bleys 2008 |
| Calcium | Tracked, no PYM target | No target found | Blood calcium is held in a narrow range by parathyroid hormone whatever the diet does, so a value inside the range says the control system works rather than that intake is right. Bone density, not serum calcium, is the measure of skeletal calcium, and PYM sets no serum target. No source, because there is no target to support. |
| Methylmalonic acid | Under 271 nmol/L | Tier 3 Functional sufficiency | Methylmalonic acid rises when a cell is functionally short of B12, which makes it the textbook sufficiency marker. The ceiling of 271 nmol/L is the NIH Office of Dietary Supplements Health Professional fact sheet’s own figure, cite-locked on 2026-09-15. Ceiling only — there is no floor a member should aim for. MMA also rises with age and with falling kidney function, so a raised value with a low eGFR is not automatically B12. Sources: National 2024 |
| Zinc | Tracked, no PYM target | No target found | Deficiency cut-offs exist and vary by sex, time of day and whether the member had eaten, none of which our draw records. Beyond the deficiency line no concentration has been shown to be better than another, and serum zinc falls in any inflammation regardless of intake, so a low number can mean two quite different things. Reported without a target. No source, because there is no target to support. |
| Copper | Tracked, no PYM target | No target found | The published association runs one way with no turning point: higher copper tracks higher mortality across the range studied, which gives a direction and no number. A direction alone would make any ceiling here arithmetic rather than evidence. Copper also rises with inflammation and with oestrogen, so a single value carries more than nutritional status. No source, because there is no target to support. |
| Leptin | Tracked, no PYM target | No target found | Leptin is produced in proportion to fat mass, so it partitions by adiposity before anything else and the sexes differ severalfold at the same weight. Once body fat is accounted for, the outcome signal largely goes with it — which means any target would be a restatement of body composition rather than an independent one. No source, because there is no target to support. |
| C-peptide | Tracked, no PYM target | No target found | A Danish general-population study established fasting reference intervals on a named analyser, which is the right kind of source, but the intervals are not in the part of the paper we could read and C-peptide assays are not standardised between platforms. Reported without a target until the numbers can be read rather than inferred. No source, because there is no target to support. |
| Creatine kinase | Tracked, no PYM target | No target found | An enzyme released when muscle is damaged, which makes it a safety marker in specific situations — statin-associated muscle injury, or a suspected rhabdomyolysis — rather than something to optimise. The number is dominated by recent exercise: a hard resistance session raises it several-fold for days in a healthy person, and it runs higher in men and in people with more muscle. A threshold that means something in one of those contexts means nothing in the other, so PYM reports it without a target. No source, because there is no target to support. |
| HbA1c | Tracked, no PYM target | No target found | The ADA threshold at 5.7% is a diagnosis line, not a wellness target, and the shipped 4.8 to 5.4% band was drawn from mortality-cohort floors with no cite-locked source behind the pairing. Pulled on 2026-09-15 with no replacement rather than reworked into a Tier-5 substitute. No source, because there is no target to support. |
| Fasting insulin | Tracked, no PYM target | No target found | SEARCHED_NONE: no defensible optimal band exists for fasting insulin, and the shipped 2 to 6 µIU/mL zone matched the same unsupported shape as a competitor’s marketed "under 5" claim. Pulled on 2026-09-15. No source, because there is no target to support. |
| Fasting glucose | Tracked, no PYM target | No target found | The ADA’s under-100 mg/dL line is a diagnosis threshold, not a wellness target, and Tirosh 2005 gives a within-normal-range risk slope rather than a floor-and-ceiling pair. The shipped 70 to 90 mg/dL band was not drawn from either source. Pulled on 2026-09-15 with no replacement. No source, because there is no target to support. |
| Vitamin B12 | Tracked, no PYM target | No target found | The shipped 500 to 1500 pg/mL band scored the midpoint of a Danish age-adjusted reference interval, plus an assay-driven ceiling that is not a toxicity line, as a therapeutic target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Folate | Tracked, no PYM target | No target found | The shipped 10 to 30 ng/mL band paired an uncited homocysteine-response floor with a ceiling that was an assay cap at some laboratories, not a physiological limit. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Vitamin D | Tracked, no PYM target | No target found | The 2011 Endocrine Society guideline called 30 ng/mL sufficient and suggested 40 to 60 as a wellness target; its 2024 successor withdrew that guidance for healthy adults and advises against routine testing. The shipped 40 to 70 ng/mL band scored a withdrawn guideline recommendation as a live therapeutic target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Magnesium | Tracked, no PYM target | No target found | The shipped 1.9 to 2.4 mg/dL band placed its floor in the upper half of a population distribution and its ceiling above the 97.5th percentile, both scoring choices rather than outcome evidence, as a therapeutic target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| RBC magnesium | Tracked, no PYM target | No target found | The shipped 5.0 to 6.8 mg/dL band scored the upper half of a typical interval with no method attached — red-cell magnesium reference intervals are set per assay by each laboratory. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
Liver
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Albumin | Tracked, no PYM target | No target found | Low albumin predicts death across almost every population studied, but it falls in inflammation, malnutrition and liver disease alike, so it is a symptom of several things rather than a target of its own. No published work names a level a healthy adult should aim for, so PYM sets none and reports the number. No source, because there is no target to support. |
| Total protein | Tracked, no PYM target | No target found | A sum of two things that move for unrelated reasons, which is why no guideline body sets a target for the sum. It earns its place on a panel as a cross-check on albumin and globulin, and PYM reports it without a target of its own. No source, because there is no target to support. |
| Total bilirubin | Tracked, no PYM target | No target found | Higher bilirubin is associated with lower mortality in several cohorts, which would make it a "higher is better" marker, but the association was quartile-based and in the largest US analysis held only within fatty liver disease. An association without a threshold is not a target, so PYM reports the number. No source, because there is no target to support. |
| Alkaline phosphatase | Tracked, no PYM target | No target found | Tonelli 2009 found a graded association between higher alkaline phosphatase and death in a US population sample, which gives a direction and no cut-point: the finding compares thirds of a distribution, not values. A direction alone would make any zone here arithmetic, so PYM reports the number. No source, because there is no target to support. |
| ALT | Tracked, no PYM target | No target found | The shipped 0 to 30 U/L ceiling scored a clinical-gastroenterology 'truly normal' reference band, itself split by sex (29 to 33 U/L for men, 19 to 25 for women), as one flat wellness ceiling. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| AST | Tracked, no PYM target | No target found | The shipped 0 to 30 U/L ceiling was set to match ALT's ceiling rather than AST's own evidence, which the ACG guideline does not state. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| GGT | Tracked, no PYM target | No target found | The shipped 0 to 30 U/L ceiling scored a healthy-cohort reference interval (Nordic Reference Interval Project) as a wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
Kidney
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Cystatin C | Tracked, no PYM target | No target found | The shipped 0.63 to 0.85 mg/L band (0.54 to 0.74 for women) scored an age- and sex-partitioned healthy-cohort reference interval as a therapeutic wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement; age bands await a clinician regardless. No source, because there is no target to support. |
| Urine albumin/creatinine ratio | Under 30 mg/g | Tier 1 Guideline threshold | KDIGO places normal albumin excretion below 30 mg/g, moderately increased from 30 to 300, and severely increased above that. The ceiling is the first line and there is no floor. This one is deliberately NOT age-banded: more than a tenth of adults past fifty exceed 30 mg/g, and that is early kidney disease rather than a normal finding for their age, so an age band would hide the finding worth having. Sources: KDIGO 2024 |
| Sodium | 135 to 142 mmol/L | Tier 2 Risk inflection in cohort data | Set on a risk curve, and only on one side of it. Following 15,752 adults enrolled in middle age for twenty-five years, a serum sodium above 142 mmol/L carried a 39 percent higher risk of developing a chronic disease and a 50 percent higher chance of testing biologically older than chronological age; above 144, a 21 percent higher risk of dying early. The enrolment ages in that study are the ages of our own members. The ceiling is that 142. The floor is not from the same evidence and does not pretend to be: 135 is the bottom of the clinical normal range, below which low sodium is a problem in its own right, and the study says nothing about the low side. Read this as a hydration marker rather than a salt marker. Sources: Dmitrieva 2023 |
| Urine red blood cells | Under 2 /hpf | Tier 1 Guideline threshold | A guideline definition with nothing inferred. Three or more red cells per high-power field on a single microscopic specimen is microhematuria under the 2020 AUA/SUFU guideline, so the target is two or fewer. It is an absolute threshold: not partitioned by age or sex, and deliberately not age-banded, for the same reason as the urine albumin ratio — blood in the urine becoming commoner with age does not make it normal. A dipstick positive for blood is a different test; the guideline rests the definition on microscopy. Sources: Barocas 2020 |
| Potassium | Tracked, no PYM target | No target found | Searched for a target on 2026-09-11 and none held up: the cohorts that report a U-shaped mortality curve for potassium are in specific disease populations and point in opposite directions, and no general-population nadir was found. Reported without a target rather than given one from a population percentile. No source, because there is no target to support. |
| Chloride | Tracked, no PYM target | No target found | Chloride is interpreted as part of a pattern with sodium and bicarbonate, not as a number with its own optimum, and no outcome study sets a target for it. PYM reports it and leaves the pattern reading to the clinician. No source, because there is no target to support. |
| Carbon dioxide | Tracked, no PYM target | No target found | Total carbon dioxide is a buffer level read against breathing rate and kidney function, and its meaning comes from the direction it has moved rather than from where it sits. No published target exists for a healthy adult, so PYM sets none. No source, because there is no target to support. |
| Urine white blood cells | Tracked, no PYM target | No target found | The conventional threshold of five cells per high-power field traces back to a study of febrile infants under sixty days old, which is not a population our members belong to, and no adult threshold with comparable evidence was found. Reported without a target rather than borrowed from infants. No source, because there is no target to support. |
| eGFR | 90 to 120 mL/min | Tier 1 Guideline threshold | KDIGO stage G1, normal kidney function, is an eGFR of 90 or above; the zone floor is that threshold. The ceiling is a scoring ceiling: a very high eGFR is not better and can reflect hyperfiltration. Sources: KDIGO 2024 |
| Creatinine | Tracked, no PYM target | No target found | The shipped 0.7 to 1.1 mg/dL ceiling scored a population distribution (NHANES) as a therapeutic target; creatinine tracks muscle mass and is read with eGFR, not scored alone. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| BUN | Tracked, no PYM target | No target found | The shipped 8 to 18 mg/dL ceiling scored an age- and sex-specific reference interval from a Chinese general population — a different population than PYM's members — as a universal wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
Blood & immune
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Red cell distribution width | Tracked, no PYM target | No target found | Perlstein 2009 reports a mortality gradient rising across the whole RDW distribution with no nadir, so there is no evidence-backed floor. The shipped 11.5 to 13.0 percent band sat below the US median of 13.3 to 13.6 percent and was not drawn from the study. Pulled on 2026-09-15; an upper-quintile ceiling framed explicitly as a quintile rather than as a wellness band is a future reword, not shipped here. No source, because there is no target to support. |
| Mean corpuscular volume | Tracked, no PYM target | No target found | Cell size is a pointer to a cause rather than a thing to optimise: the same value is normal in one member and the first sign of B12 deficiency in another, depending on what else is on the panel. PYM reports it and scores the underlying markers instead. No source, because there is no target to support. |
| Mean corpuscular hemoglobin | Tracked, no PYM target | No target found | A derived index that moves with cell size and haemoglobin, both of which PYM already scores. It is diagnostic context for those two rather than a target of its own, and no guideline sets one. No source, because there is no target to support. |
| Mean corpuscular hemoglobin concentration | Tracked, no PYM target | No target found | The most stable index on a blood count, which is what makes it useful as a quality check on the sample and useless as something to aim at. PYM reports it without a target. No source, because there is no target to support. |
| Red blood cell count | Tracked, no PYM target | No target found | The count is one of three ways of saying the same thing, and haemoglobin is the one anaemia guidelines are written against — PYM scores haemoglobin and haematocrit and reports the count beside them rather than setting a third target. No source, because there is no target to support. |
| Mean platelet volume | Tracked, no PYM target | No target found | Mean platelet volume rises when the marrow is replacing platelets quickly, so it is read against the platelet count rather than alone, and it drifts with how long the sample sat before analysis. No target survives that, so PYM reports it. No source, because there is no target to support. |
| Neutrophils | Tracked, no PYM target | No target found | A share of the white-cell count that moves within hours of an infection, a hard training session or a poor night, so a single value describes a moment rather than a state. The ratio of neutrophils to lymphocytes carries the prognostic signal in the literature, and PYM does not yet compute it. No source, because there is no target to support. |
| Lymphocytes | Tracked, no PYM target | No target found | Reported as a percentage, so it falls whenever neutrophils rise even with an unchanged lymphocyte count — which is why the percentage on its own supports no target. PYM reports it, and the absolute count is the number a clinician reads against it. No source, because there is no target to support. |
| Monocytes | Tracked, no PYM target | No target found | A small share of the white-cell count with a wide normal range and no published target for a healthy adult. It is read as part of the differential pattern, and PYM reports it without a target. No source, because there is no target to support. |
| Eosinophils | Tracked, no PYM target | No target found | Driven by allergy, asthma and parasite exposure rather than by anything a longevity protocol changes, and the clinically meaningful version is the absolute count. PYM reports the percentage without a target. No source, because there is no target to support. |
| Basophils | Tracked, no PYM target | No target found | The rarest cell on the differential, so low that the difference between one value and the next is mostly counting noise on an automated analyser. Nothing published supports a target, and PYM reports the number. No source, because there is no target to support. |
| Lead | Under 3.5 µg/dL | Tier 1 Guideline threshold | The ceiling is the level at which public health bodies say to act: 3.5 micrograms per decilitre, set for adults and children alike in 2022. Read it carefully, because it is not a safety line — it is the 97.5th percentile of the US population, a statement about how common a level is rather than about whether it harms. The National Toxicology Program found sufficient evidence of harm in adults and children below 10 and below 5. So the target is the span underneath the action line, and lower is better the whole way down; there is no lead level worth aiming to reach. Sources: Council 2022, National 2012 |
| Mercury | Under 5.8 µg/L | Tier 1 Guideline threshold | The ceiling of 5.8 micrograms per litre is the blood concentration matching the US environmental agency reference dose for methylmercury, which the CDC describes as an estimated level assumed to be without appreciable harm. That reference dose was derived to protect a developing fetus, the most sensitive endpoint rather than the one most of our members are at, so this is a deliberately conservative line. Note also what the test covers: blood mercury is mostly methylmercury from fish and falls over weeks once the diet changes, while elemental and inorganic mercury are measured in urine, which PYM does not test. Sources: Centers 2004 |
| Cadmium | Under 5 µg/L | Tier 1 Guideline threshold | The ceiling is the whole-blood level occupational regulation treats as hazardous, 5 micrograms per litre. Blood cadmium reflects recent exposure; the burden that damages kidneys accumulates there over decades and is measured in urine, which PYM does not test, so a reassuring blood level is not a statement about a lifetime. Smoking is the largest source outside industrial work by a wide margin, and stopping is the intervention that moves this number. Sources: Agency 2013 |
| Neutrophil count | Tracked, no PYM target | No target found | An absolute count rather than a share, which removes the arithmetic problem the percentage has — it does not fall merely because another cell type rose. What it does not have is a target: it moves within hours of an infection, a hard training session or a poor night, and the prognostic signal in the literature belongs to the neutrophil-to-lymphocyte RATIO, which PYM does not yet compute. Reported without a target. No source, because there is no target to support. |
| Lymphocyte count | Tracked, no PYM target | No target found | The count is the version worth reading — the percentage falls whenever neutrophils rise, with no change in the lymphocytes themselves. Even so, no published work names a level for a healthy adult to aim at, and the signal that does exist is carried by the ratio to neutrophils rather than by either count alone. Reported without a target. No source, because there is no target to support. |
| Monocyte count | Tracked, no PYM target | No target found | A small, wide-ranging part of the white-cell count with no published target for a healthy adult. It is read as part of the differential pattern, and the ratio work that exists pairs it with HDL rather than treating it alone. No source, because there is no target to support. |
| Eosinophil count | Tracked, no PYM target | No target found | The absolute count is what allergy and eosinophilic-disease guidance is written against, rather than the percentage — but that guidance sets thresholds for DISEASE, not a level for a healthy adult to aim at, and the number is driven by allergy, asthma and parasite exposure rather than by anything a longevity protocol changes. No source, because there is no target to support. |
| Basophil count | Tracked, no PYM target | No target found | The rarest cell on the differential, and so low that the difference between one automated result and the next is mostly counting noise. Nothing published supports a target, and the count shares that with the percentage. No source, because there is no target to support. |
| Hemoglobin | Tracked, no PYM target | No target found | The shipped 13.5 to 17.0 g/dL band (12 to 15 for women) scored a reference interval anchored to WHO anaemia diagnosis floors as a therapeutic wellness target — a floor for diagnosing anaemia is not evidence for where a healthy adult should aim. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| White blood cells | Tracked, no PYM target | No target found | The shipped 4.0 to 8.0 K/µL band trimmed the standard laboratory interval on an uncited claim that a persistently high-normal count tracks with inflammation. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Platelets | Tracked, no PYM target | No target found | The shipped 150 to 400 K/µL band was the unmodified conventional laboratory interval, carrying no cohort or outcome evidence behind it as a wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Ferritin | Tracked, no PYM target | No target found | The shipped 50 to 200 µg/L band (30 to 150 for women) scored a WHO iron-overload risk threshold and an arbitrary floor above the WHO deficiency line as a wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement; ferritin is reported alongside iron and transferrin saturation without a target. No source, because there is no target to support. |
| Iron | Tracked, no PYM target | No target found | The shipped 60 to 150 µg/dL band scored a healthy-cohort reference interval (Nordic Reference Interval Project, around NHANES medians) as a wellness target; iron swings with meals and time of day and is never read alone. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| TIBC | Tracked, no PYM target | No target found | The shipped 250 to 400 µg/dL band was converted from a reference interval published in different units, with no interval published in these units ever attached. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Transferrin saturation | Tracked, no PYM target | No target found | The shipped 20 to 45 percent band (15 to 45 for women) scored a conventional deficiency floor, not yet cited, as a therapeutic wellness target. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement; read with ferritin, it separates deficiency from overload. No source, because there is no target to support. |
Inflammation
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| IgE | Tracked, no PYM target | No target found | Total IgE reports allergic and parasitic burden, not health, and the specific tests are what identify a trigger. The association studies report quartiles of a population rather than a level to aim for. Reported without a target. No source, because there is no target to support. |
| Rheumatoid factor | Tracked, no PYM target | No target found | Read as positive or negative against the performing assay’s own cut-off, which differs between methods. PYM stamps one zone onto every laboratory’s result, so an assay-specific cut-off cannot be that zone — and a low positive is common in healthy older adults, which is the opposite of a target. No source, because there is no target to support. |
| hs-CRP | Under 1 mg/L | Tier 2 Risk inflection in cohort data | The CDC and American Heart Association statement grades cardiovascular risk by hs-CRP as low below 1 mg/L, average from 1 to 3, and high above 3. The zone is the low-risk grade, ceiling only, and is a risk grade rather than a wellness band. Draw twice if acute illness is suspected; above 10 mg/L reads as acute or inflammatory, not chronic cardiovascular risk. Sources: Pearson 2003 |
| Homocysteine | Tracked, no PYM target | No target found | The shipped 4 to 9 µmol/L ceiling scored a meta-analysis that reports a risk SLOPE — every 5 µmol/L lower meant less ischaemic heart disease and stroke risk, with no level below which the benefit stopped — as though it named a threshold. A slope is not a cut-point. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
Lipids & cardiovascular
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Lipoprotein(a) | Under 75 nmol/L | Tier 1 Guideline threshold | The National Lipid Association places low cardiovascular risk below 75 nmol/L, intermediate from 75 to 125, and high at or above 125, and the 2026 ACC/AHA guideline makes once-in-a-lifetime testing a Class 1 recommendation. The ceiling is the low-risk line. There is no floor — no amount of Lp(a) is too little. It is largely inherited and barely moves with diet or exercise, so it is read as risk stratification rather than as a target to chase. Sources: Koschinsky 2024 |
| NT-proBNP | Tracked, no PYM target | No target found | The shipped 0 to 125 pg/mL zone stamped ESC’s ambulatory rule-out screening threshold as a wellness AIM, distinct from Januzzi’s ICON acute rule-out of 300 pg/mL — the two answer different clinical questions and neither is a target for someone with no symptoms. Pulled on 2026-09-15. The ICON study, pooling 1,256 patients across four international sites, found 300 pg/mL had a 98% negative predictive value to rule out acute heart failure in a symptomatic patient, with age-banded rule-in cut-points of 450, 900 and 1800 pg/mL for ages under 50, 50 to 75, and over 75. That is stated here as context for what the number means clinically; it is an acute diagnostic threshold, not a Prime range, so PYM reports the value without a target. Context: Januzzi 2005 |
| Omega-3 total | Tracked, no PYM target | No target found | The famous 8 to 12 percent target is the Omega-3 Index, which is EPA plus DHA as a share of the fatty acids in red blood cell membranes. Our panel reports a plasma concentration in micromoles per litre. Same nutrient, different measurement, and the target does not transfer between them — which is exactly the kind of move that produces a confident wrong number. No source, because there is no target to support. |
| EPA | Tracked, no PYM target | No target found | The cardiovascular trials of EPA randomised people to a dose of a drug and measured events, not to a target plasma concentration, and their results conflict with each other. No trial supports aiming at a particular micromoles-per-litre value. No source, because there is no target to support. |
| DHA | Tracked, no PYM target | No target found | The cohort evidence associating DHA with lower risk reports it as a percentage of the fatty acids in a blood fraction, not as an absolute plasma concentration, so nothing published names a value in micromoles per litre to aim for. No source, because there is no target to support. |
| DPA | Tracked, no PYM target | No target found | The least studied of the three long-chain omega-3s, and what evidence exists reports it as a share of fatty acids rather than a concentration. Nothing supports an absolute target. No source, because there is no target to support. |
| Omega-6 total | Tracked, no PYM target | No target found | The outcome literature for omega-6 fats is written in percentages of total fatty acids, while laboratories report an absolute concentration. Converting one into the other needs a denominator the panel does not report, so no target is derivable. No source, because there is no target to support. |
| Arachidonic acid | Tracked, no PYM target | No target found | Pooled cohort analyses report arachidonic acid as a percentage of fatty acids and find no consistent harm, which undercuts the usual advice to lower it. Neither the direction nor a value is established well enough to be a target. No source, because there is no target to support. |
| Linoleic acid | Tracked, no PYM target | No target found | Pooled cohort analyses associate a higher percentage of linoleic acid with lower cardiovascular risk — the opposite of the popular advice — but they report quintiles of a percentage, and our panel reports an absolute concentration. A target built from that gap would be invented rather than derived. No source, because there is no target to support. |
| ApoB | Tracked, no PYM target | No target found | The shipped 30 to 80 mg/dL band invented a floor no guideline sets and stamped one of the National Lipid Association’s three risk-stratified intensification goals as a flat wellness ceiling. Pulled on 2026-09-15. The 2024 NLA consensus discusses apoB intensification thresholds by cardiovascular risk — 60, 70 and 90 mg/dL across rising risk — meant to guide treatment intensification, not to describe a healthy target for someone with no risk assessment on file. PYM has no risk stratum to place a member in, so no single one of the three ships as a universal ceiling; picking one (80, say) would repeat the exact error this marker was pulled for. Reported without a target. Context: Soffer 2024 |
| LDL cholesterol | Tracked, no PYM target | No target found | The shipped 40 to 100 mg/dL band invented a floor no guideline sets — there is no LDL level too low — and flattened three separate risk-stratified ceilings into one green zone. The 2019 ESC/EAS guideline sets those ceilings by cardiovascular risk category: under 100 mg/dL for moderate risk, under 70 for high risk, and under 55 for very high risk. Pulled on 2026-09-15. PYM has no risk assessment to place a member in one of the three categories, so none ships as a universal AIM; reported without a target. Context: Mach 2020 |
| HDL cholesterol | Tracked, no PYM target | No target found | The shipped 50 to 80 mg/dL band scored a risk-factor threshold and a U-shaped cohort inflection point as a flat wellness target, and the underlying evidence differs by sex in a way the flat band never expressed. Pulled 2026-09-15 (Deliverable D JOB 3) with no replacement. No source, because there is no target to support. |
| Triglycerides | Under 150 mg/dL | Tier 1 Guideline threshold | The shipped 40 to 90 mg/dL half-band scored a member against the middle of the US population distribution rather than a guideline line, and is retired (Deliverable D §2b, 2026-09-15). Both NCEP ATP III and the 2019 ESC/EAS guideline treat a fasting triglyceride under 150 mg/dL as normal. The zone is that ceiling only, with no floor. Sources: NCEP ATP III 2002, Mach 2020 |
| Total cholesterol | Under 200 mg/dL | Tier 1 Guideline threshold | The shipped 120 mg/dL floor was invented — no guideline sets a total-cholesterol floor, and a member on a statin with a genuinely low total should not be scored against one — and is retired (Deliverable D §2b, 2026-09-15). NCEP calls a total cholesterol under 200 mg/dL desirable. The zone is that ceiling only, with no floor: ApoB and LDL carry the risk signal, not the total. Sources: NCEP ATP III 2002 |
Recovery & fitness
| Marker | Prime range | Evidence | Basis and sources |
|---|---|---|---|
| Resting heart rate | 48 to 60 bpm | Tier 2 Risk inflection in cohort data | In the Copenhagen Male Study, mortality rose with resting heart rate independent of fitness: about 16% per 10 beats per minute, and three times higher above 90 than at 50 or below. The zone is the low-risk band; the floor is a scoring floor for people who are not endurance athletes. Sources: Jensen 2013 |
| Heart-rate variability | 60 to 110 ms | Under review | HRV depends on the device, the metric used, age and the time of night. A zone that does not name all four is not comparable across members, so this one is under review. No source attached yet. |
| VO₂ max | 40 to 55 mL/kg/min | Under review | In 122,000 patients tested on a treadmill, mortality fell with every step up in fitness and never levelled off, with the fittest group at a fifth of the risk of the least fit. Higher is better with no upper limit; the floor of 40 awaits its own citation, since the study grouped people by fitness percentile rather than by this number, and the ceiling is a scoring ceiling, not a health one. Context: Mandsager 2018 |
| Respiratory rate | 12 to 16 /min | Under review | The textbook adult resting range. Wearables measure it overnight, which runs lower, and the zone has not yet been set against device data. No source attached yet. |
| Sleep score | 80 to 100 | Reported, not evidence-tiered | A composite of sleep duration, depth and consistency on a 0 to 100 scale. There is no published evidence tier for a composite score; the zone treats 80 and above as a good night. No source attached yet. |
| Sleep score (WHOOP) | 80 to 100 | Reported, not evidence-tiered | WHOOP’s own nightly score on its own scale. A proprietary composite has no evidence tier; the zone treats 80 and above as a good night. No source attached yet. |
| Daily steps | 8000 to 12000 | Tier 2 Risk inflection in cohort data | A meta-analysis of 15 cohorts found mortality fell with more daily steps up to about 6,000 to 8,000 for adults aged 60 and over, and 8,000 to 10,000 for younger adults, then levelled off. The zone starts at 8,000. Sources: Paluch 2022 |
8. Reference list
Every PubMed entry below was fetched from PubMed and its title checked before it was cited. Links open the abstract on PubMed, or the publisher’s page for a source that is not a journal article.
- Rahmani J, Montesanto A, Giovannucci E, et al. Association between IGF-1 levels ranges and all-cause mortality: a meta-analysis. Aging Cell, 2022. PubMed 35048526
- Kim B, Cho Y, Ku CR, Lee SG, Lee KA, Kim JH. Establishment of reference intervals for serum insulin-like growth factor I in Korean adult population. Endocrinology and Metabolism, 2020. PubMed 33212546
- Koschinsky ML, Bajaj A, Boffa MB, et al. A focused update to the 2019 NLA scientific statement on use of lipoprotein(a) in clinical practice. Journal of Clinical Lipidology, 2024. PubMed 38565461
- Dmitrieva NI, Gagarin A, Liu D, Wu CO, Boehm M. Middle-age high normal serum sodium as a risk factor for accelerated biological aging, chronic diseases, and premature mortality. EBioMedicine, 2023. PubMed 36599719
- Hurst R, Armah CN, Dainty JR, et al. Establishing optimal selenium status: results of a randomized, double-blind, placebo-controlled trial. American Journal of Clinical Nutrition, 2010. PubMed 20181815
- Bleys J, Navas-Acien A, Guallar E. Serum selenium levels and all-cause, cancer, and cardiovascular mortality among US adults. Archives of Internal Medicine, 2008. PubMed 18299496
- Catalona WJ, Partin AW, Slawin KM, et al. Use of the percentage of free prostate-specific antigen to enhance differentiation of prostate cancer from benign prostatic disease: a prospective multicenter clinical trial. JAMA, 1998. PubMed 9605898
- Barocas DA, Boorjian SA, Alvarez RD, et al. Microhematuria: AUA/SUFU guideline. The Journal of Urology, 2020. PubMed 32698717
- Council of State and Territorial Epidemiologists; CDC/NIOSH. Blood lead level reference values for adults. CDC National Institute for Occupational Safety and Health, 2022. Source
- National Toxicology Program. NTP monograph on health effects of low-level lead. NTP Monograph, 2012. PubMed 23964424
- Centers for Disease Control and Prevention. Blood mercury levels in young children and childbearing-aged women, United States, 1999-2002. MMWR Morbidity and Mortality Weekly Report 53(43), 2004. Source
- Agency for Toxic Substances and Disease Registry. Case studies in environmental medicine: cadmium toxicity, laboratory evaluation. ATSDR, 2013. Source
- Oesterling JE, Jacobsen SJ, Chute CG, et al. Serum prostate-specific antigen in a community-based population of healthy men. Establishment of age-specific reference ranges. JAMA, 1993. PubMed 7688054
- Morgan TO, Jacobsen SJ, McCarthy WF, Jacobson DJ, McLeod DG, Moul JW. Age-specific reference ranges for prostate-specific antigen in black men. New England Journal of Medicine, 1996. PubMed 8663870
- Soffer DE, Marston NA, Maki KC, et al. Role of apolipoprotein B in the clinical management of cardiovascular risk in adults: An Expert Clinical Consensus from the National Lipid Association. Journal of Clinical Lipidology, 2024. PubMed 39256087
- Januzzi JL, van Kimmenade R, Lainchbury J, et al. NT-proBNP testing for diagnosis and short-term prognosis in acute destabilized heart failure: an international pooled analysis of 1256 patients: the International Collaborative of NT-proBNP Study. European Heart Journal, 2005. PubMed 16293638
- Bhasin S, Brito JP, Cunningham GR, et al. Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. Journal of Clinical Endocrinology & Metabolism, 2018. PubMed 29562364
- Pearson TA, Mensah GA, Alexander RW, et al. Markers of inflammation and cardiovascular disease: application to clinical and public health practice. A statement for healthcare professionals from the Centers for Disease Control and Prevention and the American Heart Association. Circulation, 2003. PubMed 12551878
- Mach F, Baigent C, Catapano AL, et al. 2019 ESC/EAS guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. European Heart Journal, 2020. PubMed 31504418
- National Cholesterol Education Program Expert Panel. Third report of the National Cholesterol Education Program (NCEP) Expert Panel on detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel III): final report. Circulation, 2002. PubMed 12485966
- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney International, 2024. PubMed 38490803
- Jensen MT, Suadicani P, Hein HO, Gyntelberg F. Elevated resting heart rate, physical fitness and all-cause mortality: a 16-year follow-up in the Copenhagen Male Study. Heart, 2013. PubMed 23595657
- Mandsager K, Harb S, Cremer P, et al. Association of cardiorespiratory fitness with long-term mortality among adults undergoing exercise treadmill testing. JAMA Network Open, 2018. PubMed 30646252
- Paluch AE, Bajpai S, Bassett DR, et al. Daily steps and all-cause mortality: a meta-analysis of 15 international cohorts. The Lancet Public Health, 2022. PubMed 35247352
- Rupprecht M, Wagenpfeil S, Schöpe J, Vieth R, Vogt T, Reichrath J. Meta-Analysis of European Clinical Trials Characterizing the Healthy-Adult Serum 25-hydroxyvitamin D Response to Vitamin D Supplementation. Nutrients, 2023. PubMed 37764770
- Kavyani Z, Musazadeh V, Fathi S, Hossein Faghfouri A, Dehghan P, Sarmadi B. Efficacy of the omega-3 fatty acids supplementation on inflammatory biomarkers: An umbrella meta-analysis. International Immunopharmacology, 2022. PubMed 35914448
- AbuMweis S, Jew S, Tayyem R, Agraib L. Eicosapentaenoic acid and docosahexaenoic acid containing supplements modulate risk factors for cardiovascular disease: a meta-analysis of randomised placebo-control human clinical trials. Journal of Human Nutrition and Dietetics, 2018. PubMed 28675488
- Zhao JV, Huang X, Zhang J, Chan YH, Tse HF, Blais JE. Overall and Sex-Specific Effect of Berberine on Glycemic and Insulin-Related Traits: a Systematic Review and Meta-Analysis of Randomized Controlled Trials. The Journal of Nutrition, 2023. PubMed 37598753
- Jovanovski E, Yashpal S, Komishon A, et al. Effect of psyllium (Plantago ovata) fiber on LDL cholesterol and alternative lipid targets, non-HDL cholesterol and apolipoprotein B: a systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition, 2018. PubMed 30239559
- Sohouli MH, Almuqayyid F, Alfardous Alazm A, et al. A comprehensive review and meta-regression analysis of randomized controlled trials examining the impact of vitamin B12 supplementation on homocysteine levels. Nutrition Reviews, 2024. PubMed 37495210
- National Institutes of Health, Office of Dietary Supplements. Vitamin B12 — Health Professional Fact Sheet. NIH Office of Dietary Supplements, 2024. Source
Questions about a range, or a source you think is missing: email support@primeyearsmedical.com, or raise it with your provider at your next review.
Prime ranges, the Prime Score, and the biological-age model are decision-support tools, not a diagnosis. They do not replace your provider’s clinical judgment. Methodology and copy pending clinical and legal review.