Research
Mixed
Among never smokers, the lowest all-cause mortality risk is associated with a BMI of 23-24, indicating that overweight (BMI 25-29.9) is associated with increased mortality risk.
If you are a never smoker, aiming for a BMI between 23 and 24 appears to offer the lowest mortality risk based on this large-scale evidence. If you are currently overweight, this data suggests moving toward that range may reduce mortality risk, contrary to claims that overweight is protective.
WeakQualifiesVERY_HIGH confidence
In never smokers and healthy never smokers, there was a J shaped association between BMI and mortality, and the lowest risk was observed at BMI 23-24 and 22-23, respectively
Why this rating
Meta-analysis of 230 cohort studies with 30.3 million participants.
Source
BMI and all cause mortality: systematic review and non-linear dose-response meta-analysis of 230 cohort studies with 3.74 million deaths among 30.3 million participants
Dagfinn Aune et al. · BMJ · 2016
DOI 10.1136/bmj.i2156
Meta-analysis · 230 studiesCited 956×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
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
- Severely protein-deficient diets (2–3% energy) induce lean body mass loss and metabolic imbalance, whereas adequate protein intake (0.66 g/kg/d minimum) is a prerequisite for maintaining muscle, bone, and physiological function.Strong
- 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
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →