Research
Mixed
Unintentional weight loss is associated with a significant increase in all-cause mortality risk.
If you are losing weight without trying, consult a doctor. This is often a sign of an underlying health issue that needs to be addressed, rather than a fitness goal.
ModerateSupportsMEDIUM confidence
Weight loss which was unintentional or ill-defined was associated with excess risk of 22 to 39 %.
Why this rating
Meta-analysis of prospective cohort studies.
Source
A review and meta-analysis of the effect of weight loss on all-cause mortality risk
M. G. Harrington et al. · Nutrition Research Reviews · 2009
DOI 10.1017/s0954422409990035
Meta-analysis · 26 studiesCited 253×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Intentional weight loss in healthy, overweight (non-obese) individuals is associated with a statistically significant increase in all-cause mortality risk compared to weight stability.Moderate
- Intentional weight loss in unhealthy individuals (those with obesity-related risk factors or diabetes) reduces all-cause mortality risk.Moderate
Related findings · Mixed
- Bariatric surgery (VSG and RYGB) is the most effective and sustainable treatment for obesity, producing marked and sustained weight loss that non-surgical interventions cannot match.Strong
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- For patients with Class III obesity (BMI >39.9 kg/m2), metabolic bariatric surgery (MBS) is significantly more effective than any currently approved medication, with BilioPancreatic Diversion (BPD) showing the highest estimated weight loss.Strong
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