Integrated Wellness Evidence Library

Every claim, graded and cited.

Physician-reviewed summaries of the science behind our clinical concepts — what is established, what is emerging, and where the limits are. Every page carries peer-reviewed references and an explicit evidence grade.

Evidence AEvidence BEvidence CEvidence Emerging

Evidence · LongevityEvidence B

Biological Age & Epigenetic Clocks

Epigenetic clocks estimate biological age from DNA methylation patterns and are among the best-validated molecular aging biomarkers: second- and third-generation clocks (PhenoAge, GrimAge) predict morbidity and mortality better than chronological age. Their key limitation is that a molecular estimate can diverge from vascular function and real-world physiological reserve — which is why Integrated Wellness assesses biological age across three independent pillars.

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Evidence · MetabolicEvidence A

Insulin Resistance & Metabolic Health

Insulin resistance — reduced cellular response to insulin — is the central driver of type 2 diabetes and a major contributor to cardiovascular risk, described by Reaven's landmark 1988 Banting Lecture. It develops years before glucose becomes abnormal, and population data suggest only about 1 in 8 American adults meets criteria for optimal metabolic health, making early measurement one of the highest-yield actions in preventive medicine.

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Evidence · HormonesEvidence A

Testosterone Therapy: Evidence & Safety

For men with confirmed hypogonadism, testosterone therapy improves sexual function, mood, bone density and lean mass, per Endocrine Society clinical practice guidelines. The 2023 TRAVERSE trial — over 5,000 men at elevated cardiovascular risk — found testosterone non-inferior to placebo for major adverse cardiac events, addressing the field's largest safety question. Therapy still requires proper diagnosis, conservative titration and scheduled monitoring.

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Evidence · HormonesEvidence A

Menopausal Hormone Therapy

Menopausal hormone therapy is the most effective treatment for vasomotor symptoms and genitourinary syndrome of menopause. Long-term Women's Health Initiative follow-up (Manson 2017, JAMA) found no increase in all-cause mortality over 18 years, and current consensus holds that for healthy women under 60 or within 10 years of menopause onset, benefits generally outweigh risks — with individualized, physician-supervised decision-making.

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Evidence · MicrobiomeEvidence B

The Gut Microbiome & Systemic Health

Humans host roughly as many bacterial cells as human cells (Sender 2016), and the gut microbiome participates in digestion, immune regulation, metabolism and gut-brain signaling (Cryan 2019). Diet measurably reshapes microbial composition within weeks (Valdes 2018, BMJ). Testing is genuinely informative for guiding nutrition strategy — but it is an assessment tool, not a diagnostic, and single-sample results require careful interpretation.

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Evidence · WearablesEvidence B

HRV, Sleep & Wearable Data in Clinical Context

Wearable-derived signals map onto well-validated physiology: heart rate variability reflects autonomic function (Shaffer & Ginsberg 2017), adult sleep of 7+ hours is a consensus health recommendation (Watson 2015), and cardiorespiratory fitness shows one of the strongest inverse associations with long-term mortality ever measured (Mandsager 2018). The evidence supports wearables as longitudinal context for clinical decisions — not as standalone diagnostics.

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