§ Claim under review · Study
"A study following over 140,000 people found that every 5kg weaker a person's grip strength was, their risk of dying from any cause increased by an additional 16%." Secondary claims in the same post: (a) "people with the highest grip strength had a 70% lower chance of getting and dying from dementia" (b) Caption: "here are benchmarks from the actual study" (men under 90 lb below average, 90 to 125 lb average, 125 lb+ above average; women under 50 / 50 to 75 / 75+)
Verdict
Mostly accurate
Confidence
HighSummary
The main statistic in this post checks out. It comes from the PURE study published in The Lancet in 2015, which followed about 140,000 adults in 17 countries and found that every 5 kg of lower grip strength was linked to a 16% higher risk of death from any cause, even after accounting for age, education, smoking, activity and existing illness. Two caveats matter. The study tracked people for a median of only four years, so it measures short-term risk, not how long someone will live. And the post's second figure is wrong: the dementia research it alludes to found that the weakest group had about 72% higher dementia risk than the strongest, which is not the same as the strongest group having a 70% lower risk. The grip strength benchmarks listed in the caption also do not match the numbers published in the study, especially for men. The video is right about the most important point: grip strength is a marker of overall health and muscle function, and there is no evidence that training your grip by itself makes you live longer.
The readings
key figures from the evidenceall-cause mortality hazard ratio per 5kg lower grip strength
PURE study participants analysed for mortality
higher dementia incidence in lowest vs highest grip quintile
Why this verdict
Evidence
The cited study is real, correctly identified by PMID, and the headline number matches.
Grip strength was inversely associated with all-cause mortality, with a hazard ratio per 5 kg reduction in grip strength of 1.16 (95% CI 1.13 to 1.20; p<0.0001), alongside cardiovascular mortality (1.17, 1.11 to 1.24) and non-cardiovascular mortality (1.17, 1.12 to 1.21).
Between January 2003 and December 2009, 142,861 participants were enrolled in PURE, of whom 139,691 with known vital status were included in the analysis, and during a median follow-up of 4.0 years (IQR 2.9 to 5.1), 3,379 (2%) died.
Participants were aged 35 to 70 years and drawn from three high-income, ten middle-income and four low-income countries, with grip strength measured using a Jamar dynamometer.
Associations held after accounting for socioeconomic status, other health conditions and education, and grip strength was a significantly stronger predictor of all-cause mortality than systolic blood pressure.
Findings
✓ What's accurate 5
- The study exists, is correctly cited by PMID, and is a high-quality Lancet publication.
- The 16% figure is exact: HR 1.16 per 5 kg lower grip strength for all-cause mortality.
- The sample size is essentially right: 142,861 enrolled, 139,691 analysed.
- The association survived adjustment for age, sex, education, physical activity, smoking, alcohol and comorbidities, and held across sexes, age groups and country income levels.
- The video's own caveat is correct and unusually responsible: grip strength is a proxy for overall strength and physical function rather than a cause of longevity.
≈ What's misleading 5
- Temporal overreach: "predict how long you're going to live" implies lifespan prediction. The study's median follow-up was 4.0 years with 2% mortality. It measures short-to-medium term risk stratification, not life expectancy.
- Risk inversion (secondary claim a): "70% lower chance of getting and dying from dementia" misstates a finding that the weakest group had about 72% higher dementia incidence and 87% higher dementia mortality. Inverting a relative risk this way inflates the apparent benefit. The figure also comes from UK Biobank, not from the 140,000-person study the post credits.
- Marketing-style benchmarking (secondary claim b): the caption presents the lb cut-offs as "benchmarks from the actual study," but they do not correspond to the PURE grip distribution reported in the paper, particularly for men.
- Minor overstatement: "over 140,000" slightly exceeds the 139,691 actually analysed, though enrolment was 142,861.
- Implied intervention benefit: the dead-hang test and grip training advice imply that raising grip strength lowers mortality. PURE was observational and did not test whether improving grip strength changes outcomes.
? What's uncertain 3
- Whether raising grip strength through training reduces mortality risk. No randomised evidence was found addressing this, and the cited study cannot answer it.
- The exact origin of the lb benchmarks in the caption. They resemble general dynamometer norm charts rather than PURE's published tables, but I could not identify the specific source.
- Residual confounding. Weak grip can be an early marker of undiagnosed illness, and a 4-year follow-up window makes reverse causation harder to rule out fully.
Sources
5 of 5 linked to recordsLeong DP et al., "Prognostic value of grip strength: findings from the Prospective Urban Rural Epidemiology (PURE) study," The Lancet 386(9990):266-273, 2015, PMID 25982160
Esteban-Cornejo / Sánchez et al., "Handgrip strength and all-cause dementia incidence and mortality: findings from the UK Biobank prospective cohort study," J Cachexia Sarcopenia Muscle, 2022
PURE reference-range paper, "Reference ranges of handgrip strength from 125,462 healthy adults in 21 countries"
Medscape / heartwire coverage of the PURE grip paper
2 Minute Medicine summary of PURE