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Rapamycin extends mouse lifespan 9–14%
NAD+ precursors reverse aging in humans
Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
Verdict change — caffeine half-life downgraded

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What references ranges does Peter consider too broad on lab tests? (AMA #3) — Whalespan

Content›Video›What references ranges does …

What references ranges does Peter consider too broad on lab tests? (AMA #3)

Peter Attia17m · 2020-01-24

Claims Made

31

Claims Supported

18

Support Rate

58%

Support rate

18 of 31 claims supported

18 supported13 partial / not

Claims from this content

28

✓Well SupportedThe increase in growth hormone from sauna use is likely due to increased activity of hypothalamic neurons that regulate heat and stimulate growth hormone release.✓Well SupportedOptimal two-hour glucose after a 75g glucose challenge should be below 100 mg/dL and insulin ideally below 20 or approximately twice the one-hour insulin level.✓Well SupportedPeter Attia's lowest IGF levels occurred during three years on a ketogenic diet, where they were in the 25th percentile for age.✓Well SupportedElevated IGF-1 leads to negative feedback, lowering HGH production, and as IGF-1 declines, HGH release is stimulated.Partially Supported

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Attia walks back the clinic protocol: too aggressive for healthy adults

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AV

A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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N. Park

2d

Would love a "what would change this verdict" RSS feed. Sign me up if it exists.

◐

Free T3 levels indicate peripheral T4 conversion to T3, while reverse T3 levels indicate peripheral T4 conversion to reverse T3.

✓Well SupportedPeter Attia measures oxidized LDL (oxLDL) because it is easy to perform and is more directly linked to the atherosclerotic process than MPO.

◐Partially SupportedBiochemically optimal thyroid function is indicated by TSH between 0.5-2.0, free T3 above 3.0, and reverse T3 below 12.

✕Not SupportedOverly suppressing cholesterol synthesis, particularly with statins, may pose a risk at the individual level.

◐Partially SupportedOptimal fasting glucose should be below 90 mg/dL, fasting insulin below 6, and at 1 hour post-75g glucose challenge, glucose below 120-130 mg/dL and insulin below 20-30.

◐Partially SupportedPeter Attia prefers LDL particle number below 1000 nmol/L for preventing the most common cause of death.

◐Partially SupportedIGF-1 levels provide a more stable, long-term view of physiological state compared to pulsatile hormones like growth hormone.

◐Partially SupportedPeter Attia prefers ALT levels below 20 and AST levels below 20, considering standard lab upper limits of ~44 for ALT and ~40 for AST to be unnecessarily high.

◐Partially SupportedPeter Attia no longer believes IGF-1 and growth hormone should be minimized for longevity.

◐Partially SupportedAggressive goals for non-HDL cholesterol are maintained by Peter Attia and his colleagues.

◐Partially SupportedMeasuring growth hormone (GH) in blood tests is generally difficult to interpret outside of extreme pathological cases.

◐Partially SupportedThe three main factors impacting IGF-1 are amino acid intake, insulin levels, and exogenous growth hormone.

◐Partially SupportedPeter Attia prefers uric acid below 5.0 mg/dL, noting that higher levels may have health consequences.

◐Partially SupportedIGF levels are more stable than GH levels.

◐Partially SupportedThe ideal EPA/DHA index in red blood cells should be above 8.5%, with levels up to 10-12% tolerated if no adverse effects occur.

◐Partially SupportedThe relative ratio of DHEA to EPA/DHA may be more important than the absolute EPA/DHA index.

◐Partially SupportedMeasuring growth hormone (GH) and ACTH is difficult for assessing pituitary function outside of extreme pathological cases due to their pulsatile nature.

◐Partially SupportedPeter Attia prefers C-reactive protein below 1 mg/L.

◐Partially SupportedEpidemiology is a poor tool for health interventions, but contrasting IGF-1 levels with disease is a less flawed approach.

◐Partially SupportedDuring tissue and organ regeneration, IGF-1 levels are likely not at their lowest but are rebounding, indicating synthesis.

◐Partially SupportedDesmosterol is an important sterol to measure, and Peter Attia prefers to see it above 0.5.

◐Partially SupportedHigh-frequency moving hormones can be too noisy for interpretation due to pulsatile nature.

◐Partially SupportedPeter Attia disregards standard laboratory reference ranges and uses his own set of physiological standards.

◐Partially SupportedThe oral glucose tolerance test is a better diagnostic tool for type 2 diabetes than hemoglobin A1c.