Myths, with facts

The most common claims on the longevity market — and what research says.

28 / 28 results

Myths, with facts

„Antioxidant supplements (vitamins C, E, beta-carotene) extend life.”

Cochrane's review of 78 RCTs (n=296,707) found beta-carotene and vitamin E supplements INCREASED mortality, vitamin C was neutral. Free radicals are partly signalling molecules: high doses even blunt exercise adaptation.

Mostly false

„A daily glass of red wine is good for the heart.”

The “J-curve” came from cohort bias: abstainers include many ex-drinkers and sick people. With Mendelian randomisation (genetic alcohol tolerance) the protection vanishes, and resveratrol doesn't protect humans. Lowest risk: zero.

False

„You can't build muscle after 60.”

Even 90-year-old nursing-home residents increased strength 174% with 8 weeks of resistance training (Fiatarone 1990, JAMA). Older muscle responds more slowly but just as surely: it needs more protein and load, not resignation.

Mostly false

„You can catch up on weekday sleep debt at the weekend.”

Depner 2019 RCT: weekend recovery sleep did not restore insulin sensitivity, and the next week was worse still. Irregular sleep timing is a mortality risk in itself (Windred 2024). It helps after a brief, occasional shortfall; not as a habit.

False

„Running ruins your knees.”

Meta-analysis of 25 studies (n=125,810): recreational runners had 3.5% knee/hip osteoarthritis versus 10.2% in non-runners. Only elite-level, very high volume raised risk (13.3%). Cartilage strengthens under load and weakens with sitting.

False

„Detox and juice cleanses purge the body of toxins.”

Liver and kidneys “detox” continuously; no cleanse has ever named a measurable toxin it removes (Klein & Kiat 2015 review). Juice cleanses bring sugar loads and muscle loss. What actually helps: cutting alcohol, fibre, sleep.

Mostly false

„NMN reverses ageing in humans.”

NMN reliably raises blood NAD+, and a couple of small trials improved single markers (insulin sensitivity, walking distance). “Reversing ageing” is a mouse result (Sinclair lab); in humans there is no lifespan or hard-endpoint data.

Mostly false

„Intermittent fasting works better than plain calorie restriction.”

Liu 2022 NEJM (12 months): an 8-hour window plus calorie restriction lost the same as calorie restriction alone, with no difference in lipids or glucose. Fasting is a tool for eating less — good if it's easier for you to stick to.

Mixed

„Eggs dangerously raise cholesterol.”

Dietary cholesterol barely moves blood LDL in most people (the liver compensates); an egg a day didn't raise heart disease in cohorts. But “hyper-responders” (≈25%) and diabetics react differently — let ApoB decide, not dogma.

Mostly false

„Ice baths are a serious fat-burner and life-extender.”

Cold water activates brown fat, but the daily calorie effect is trivial (tens to a hundred kcal), and winter swimmers' weight didn't differ (Søberg 2021). It does lift mood and alertness instantly. After strength training it blunts hypertrophy. No lifespan data.

Mixed

„Blue Zone populations are all vegetarian.”

They eat plant-leaning, legume-rich diets, but Sardinia has cheese and lamb, Okinawa pork, Ikaria fish — meat portions are small, not zero. Daily movement and community are the bigger common threads. Some Blue Zone data (birth records) are disputed.

False

„Coffee harms the heart and shortens life.”

UK Biobank (n=498,134): 2–4 cups a day meant 12–14% lower all-cause mortality, decaf included. Coffee drinkers have less fatty liver, type 2 diabetes and Parkinson's. What matters: no sugar or cream, none after 2 pm.

Mostly false

„You must drink 8 glasses (2 litres) of water a day; thirst is already too late.”

The “8×8” rule has no scientific source. The 2022 Science study (n=5,604, 23 countries) found daily water turnover ranges from 1 to 6 litres; food supplies 20–30% of intake, and coffee and tea count. With healthy kidneys thirst is an accurate signal — exceptions: the elderly (blunted thirst), heat, exercise, kidney-stone tendency. Over-drinking (hyponatraemia) has killed marathoners.

Mixed

„You need 10,000 steps a day for health.”

10,000 was the marketing number of a 1965 Japanese pedometer (Manpo-kei). Meta-analyses (Paluch 2022, n=47,471) show mortality plateaus at ~6,000–8,000 steps over 60 and 8,000–10,000 in younger people; the biggest gain lies between 2,000 and 6,000. Pace matters too: brisk steps count more. So: 10,000 doesn't hurt, but 7,000 already delivers 80% of the benefit.

Mostly false

„Collagen powder can't work because the stomach digests it — a waste of money.”

The di- and tripeptides of hydrolysed collagen (prolyl-hydroxyproline) demonstrably appear in blood and skin and act as signals that stimulate fibroblasts. Meta-analysis (19 RCTs, n=1,125): 2.5–10 g/day over 8–12 weeks measurably improves skin hydration and elasticity; a small effect on knee pain. What's true in the myth: the effect is modest, and most trials were manufacturer-funded.

Mostly false

„Statins cause muscle pain in most users and wreck the liver.”

The SAMSON trial (2020) gave the same patients statin, placebo and nothing in rotation: 90% of symptoms appeared on placebo too (nocebo effect). A meta-analysis of blinded RCTs (n=154,664) puts statin-caused muscle symptoms at ~1% of users, mostly in the first year. Serious liver injury is <1 case per million users. What's true: type 2 diabetes risk rises about 10% (NNH ≈ 250), which the cardiovascular benefit outweighs several times over.

Mostly false

„Salt only harms people who already have high blood pressure.”

The SSaSS trial (2021, n=20,995, 5 years) replaced 25% of table salt with potassium chloride and cut stroke 14% and mortality 12% across an entire village population — not just in hypertensives. The blood-pressure response varies (salt sensitivity), but the risk curve is continuous even below 120/80. European intake is 8–11 g a day against a 5 g recommendation; 80% comes from processed food, not the shaker.

Mostly false

„Breakfast is the most important meal of the day; skipping it makes you fat.”

The line comes from a 1944 General Foods cereal campaign. The BMJ meta-analysis (13 RCTs, 2019) found breakfast eaters consume ~260 kcal more per day, and skipping breakfast doesn't cause weight gain — if anything, slight loss. What's true: eating earlier in the day (early dinner, not late) is better for insulin sensitivity, and breakfast improves attention in children. The adult decision: the end of the eating window matters, not whether breakfast exists.

Mostly false

„High protein intake damages the kidneys.”

No evidence in healthy kidneys: a meta-analysis of RCTs (Devries 2018, n=1,358) found 1.5–2.2 g/kg protein didn't worsen GFR; filtration rises adaptively. The myth stems from ALREADY damaged kidneys (CKD 3+), where protein restriction (0.6–0.8 g/kg) really does slow decline. In healthy older adults the opposite is the problem: too little protein causes sarcopenia. Check eGFR, and if normal, 1.2–1.6 g/kg is safe.

Mixed

„A home epigenetic test tells my biological age precisely and can track what works.”

Epigenetic clocks (Horvath, GrimAge, DunedinPACE) are real predictors of mortality at the population level. At the individual level, though, test-retest error is ±3–5 years (Higgins-Chen 2022), different clocks give ages 10 years apart from the same sample, and it's unknown whether a 2-year “rejuvenation” actually means a longer life. Usable: yearly, same test, for the trend. Not usable: to measure a supplement's 3-month effect.

Mostly false

„Artificial sweeteners make you as fat as sugar and cause cancer.”

In RCTs swapping sugary drinks for sweetened ones produces weight loss (–1–2 kg, 2022 meta-analysis); the “fattening” claim comes from reverse causation in cohorts (heavier people drink more diet soda). Cancer: aspartame's IARC 2B rating (“possible”, like aloe vera) rests on weak evidence, and EFSA deems 40 mg/kg a day safe (≈ 14 cans). Where caution is fair: sucralose and saccharin alter gut flora in some people and can worsen glucose response (Suez 2022). Water is better — but diet soda isn't sugar.

Mixed

„Sunlight should be avoided entirely; sunscreen plus a vitamin D pill covers everything.”

The Swedish MISS cohort (n=29,518, 20 years) found sun-avoiding women had twice the mortality of the most sun-exposed — a gap comparable to smoking, and not just vitamin D: nitric oxide made in skin lowers blood pressure. Yet sunburn genuinely causes melanoma, and sunscreen halved it in an RCT (Nambour). The sensible middle: 10–20 minutes of midday sun on bare arms daily without burning; sunscreen for longer exposure. The pill replaces vitamin D, not the sun.

Mostly false

„The brain only declines after 25; memory loss in old age is inevitable.”

The hippocampus makes new neurons in adulthood, and the Erickson RCT (2011, n=120, 65+) found a year of walking INCREASED its volume by 2% (controls lost 1.4%). The FINGER trial (n=1,260) improved cognitive scores 25% in 2 years with a multidomain lifestyle programme. 45% of dementia cases trace to 14 modifiable risk factors (Lancet Commission 2024): hearing, LDL, blood pressure, inactivity, loneliness, vision… What's true: processing speed does slow — but knowledge and judgement keep growing until 70.

Mostly false

„You must stretch before exercise or you'll get injured.”

Cochrane and several RCTs (e.g. Pope 2000, n=1,538 recruits) found static stretching before exercise doesn't reduce injuries, and beyond 30 s transiently cuts strength and power by 5–8%. What protects: a dynamic warm-up (gradually rising intensity, movement-pattern drills) and progressive training load. Stretching has its place: after training or separately, for range of motion and — in older adults — for gait and fall prevention.

Mostly false

„Lifespan is mostly genetic — if your parents died young, so will you.”

A 400-million-person family-tree analysis (Ruby 2018, Ancestry) puts lifespan heritability at only ~7% — the earlier 20–30% estimates came from spouses resembling each other (assortative mating). Genetics matter more past 100, but up to 80 lifestyle dominates: in Harvard cohorts five habits (not smoking, BMI < 25, 30 minutes of exercise, moderate alcohol, good diet) added 12–14 years of life at 50. What's true: Lp(a), APOE4 and familial hypercholesterolaemia are inherited risks — but all measurable and treatable.

False

„Strength training makes women “bulky”; cardio is what they need.”

Women's testosterone is 5–10% of men's; visible bulk is hard for women to build even with years of targeted work and a calorie surplus. What strength training does for women: slows menopausal bone loss (meta-analysis: +1–2% bone density a year instead of –1% in controls), prevents sarcopenia and falls, and in the Momma cohort weekly strength training meant 30% lower cardiovascular mortality in women — a bigger effect than the 11% in men. Cardio matters too — but for women strength training is the most important missing link.

Mostly false

„Gluten harms everyone; a gluten-free diet is healthier.”

In coeliac disease (~1% of people) gluten genuinely harms, and wheat allergy exists. “Non-coeliac gluten sensitivity” in blinded trials (Biesiekierski 2013) mostly traces to FODMAP carbohydrates, not gluten. In healthy people a gluten-free diet in Harvard cohorts (n=110,017) did NOT reduce heart disease, but did mean less whole grain and fibre. Gluten-free products often carry more sugar and fat. With symptoms: coeliac screening (tTG-IgA) BEFORE removing gluten.

False

„A glass of wine a day is healthier than complete abstinence.”

The J-curve (“a little beats none”) is a cohort artefact: the abstainer group contains people who quit because of illness (“sick quitters”). Filtering that out (Stockwell 2023, 107 studies, n=4.8 million) and in Mendelian randomisation (Millwood 2019, n=512,715), no amount protects. GBD 2022 puts the safe amount at zero under 40 and ≈0.5–1 drink a day over 40 as the level where risk doesn't rise meaningfully. Cancer risk (breast, bowel, oesophagus) is linear from the first glass. The choice can be yours — but not for health.

Last reviewed: 6 September 2026

This site is educational and does not replace medical advice. Start any supplement or drug only after consulting a doctor or pharmacist.