The Healthspan Map · Ch3 Baseline: Body composition
BMI
What this is linked to
| Nutrient or lever | Direction | Strength | Evidence type | What was found | Source |
|---|---|---|---|---|---|
| BMI | Watch this | Moderate | Cohort / observational | Both obesity (impaired balance/mobility) and low BMI/malnutrition/frailty raise fall risk — a U-shaped relationship. | Falls risk-factor meta-analysis (PMC11335697) (opens in a new tab) |
| BMI | Watch this | Moderate | Cohort / observational | Fatigue tracks BOTH extremes of body weight: obesity drives it via systemic inflammation (CRP/IL-6/TNF-a), and undernutrition/underweight cause fatigue in a vicious loop (too tired to prepare meals). | Nutritional status & fatigue review (PMC7071235) (opens in a new tab) |
| BMI | Watch this | Emerging | RCT / meta-analysis | Higher BMI raises reflux/GERD risk dose-dependently (~+68% per 10 kg/m2; obesity roughly doubles risk). | Obesity & GERD meta (opens in a new tab) |
| BMI | Watch this | Strong | RCT / meta-analysis | Excess body weight raises blood pressure via fluid volume, sympathetic and RAAS activation; weight loss is a first-line non-drug lever. | "Effect of weight loss on blood pressure changes in overweight patients: A systematic review and meta-analysis", J Clin Hypertens 2023 (opens in a new tab) |
| BMI | Watch this | Moderate | Review / narrative | Excess weight, especially visceral fat, drives atherogenic dyslipidemia (higher triglycerides, lower HDL); weight loss improves the lipid profile. | Lifestyle & lipids (Endotext) (opens in a new tab) |
| BMI | Watch this | Moderate | Review / narrative | Higher body weight mechanically loads the knees and hips; weight loss reduces osteoarthritis pain. | Osteoarthritis rehabilitation review (opens in a new tab) |
| BMI | Watch this | Moderate | Review / narrative | Obesity and metabolic syndrome cause peripheral neuropathy even without diabetes, via insulin resistance and inflammation. | Diabetic neuropathy review (opens in a new tab) |
| BMI | Watch this | Moderate | Cohort / observational | Obesity lowers testosterone and nitric-oxide availability (→ ED) and drives PCOS/anovulation and poor sperm; underweight causes amenorrhea — U-shaped, and losing 5-10% of weight can restore ovulation. | Lifestyle modification & erectile dysfunction review (PMC4291878) (opens in a new tab) |
| BMI | Watch this | Moderate | Cohort / observational | Obesity worsens influenza/COVID/pneumonia outcomes, while underweight/malnutrition also raises infection risk — a U-shaped relationship. | Inflammation & pneumonia review (PMC6221464) (opens in a new tab) |
| BMI | Watch this | Strong | RCT / meta-analysis | Obesity is the leading cause of OSA; an 8-week weight-loss/lifestyle program left 62% CPAP-free at 6 months, and 10% weight loss predicts ~26% AHI reduction. | INTERAPNEA weight-loss RCT (JAMA Netw Open 2022) (opens in a new tab) |
| BMI | Watch this | Emerging | Cohort / observational | In ~5,000 adults with obesity, higher body weight (via visceral fat/leptin) predicted higher TSH within the normal range — excess weight nudges thyroid signalling upward. | Fontana et al., obesity–TSH cohort (PMC9606412) (opens in a new tab) |
| BMI | Watch this | Moderate | Cohort / observational | High BMI is a risk factor for tinnitus, likely via impaired cochlear blood flow. | Tinnitus & cardiovascular risk (opens in a new tab) |
| BMI | Watch this | Strong | Review / narrative | Excess weight, especially central (visceral) fat, is the primary driver of insulin resistance; losing weight can push type 2 diabetes into remission. | Diet & T2D prevention (Lancet) (opens in a new tab) |
| BMI | Watch this | Moderate | Cohort / observational | Obesity raises AMD risk via chronic inflammation and, through diabetes, drives retinopathy; BMI over 30 may substantially increase AMD odds. | Modifiable lifestyle & AMD review (PMC11946629) (opens in a new tab) |
| BMI | Watch this | Moderate | Review / narrative | Visceral fat secretes IL-6 and TNF-a, raising CRP and driving chronic low-grade inflammation and impaired immunity. | Obesity & inflammation (opens in a new tab) |
| BMI | Watch this | Strong | Established clinical | High BMI drives the metabolic-endocrine cluster: insulin resistance, T2D, dyslipidemia, PCOS. | Obesity clinical review (opens in a new tab) |
| BMI | Watch this | Strong | RCT / meta-analysis | BMI discriminates the cardiometabolic-risk cluster across >300,000 adults. | Ashwell et al., Obesity Reviews 2012 (opens in a new tab) |
| BMI | Watch this | Strong | Established clinical | Losing 7% of body weight resolves steatohepatitis and 10% drives fibrosis regression in fatty-liver disease; obesity is also a major driver of chronic kidney disease. | AGA lifestyle guidance (MASLD/NAFLD) (opens in a new tab) |
| BMI | Watch this | Moderate | Established clinical | Obesity raises cardiovascular disease risk via hypertension, dyslipidemia and diabetes. | Obesity clinical review (opens in a new tab) |
| BMI | Watch this | Moderate | Established clinical | Obesity causes obstructive sleep apnea and obesity-hypoventilation, raising respiratory morbidity. | Obesity clinical review (opens in a new tab) |
| BMI | Watch this | Emerging | Established clinical | Excess load promotes osteoarthritis and joint pain. | Obesity clinical review (opens in a new tab) |