Research

Mixed

In patients with type 2 diabetes, higher BMI (overweight/obese) is associated with lower all-cause mortality compared to normal weight, a phenomenon known as the 'obesity paradox'.

If you have type 2 diabetes, do not use the 'obesity paradox' as an excuse to maintain a high BMI. While some studies show obese diabetics live longer than lean ones, this is likely due to biases like muscle mass or fitness, not the fat itself. Standard medical advice remains to lose weight if overweight, as it improves metabolic markers and does not increase mortality risk.

ModerateQualifiesMEDIUM confidence
there is increasing evidence that overweight or obese patients with type 2 diabetes mellitus experience lower mortality compared with patients of normal weight. This paradoxical finding, known as the 'obesity paradox,' occurs in other chronic diseases, and in type 2 diabetes mellitus is particularly perplexing given that lifestyle intervention with one goal being weight reduction is an important feature of the management of this condition.
Seung Jin Han et al. · Diabetes & Metabolism Journal · 2018

Why this rating

Based on observational epidemiological studies with potential for significant bias (reverse causation, confounding), not RCTs proving causality.

Source

The Evidence for an Obesity Paradox in Type 2 Diabetes Mellitus

Seung Jin Han et al. · Diabetes & Metabolism Journal · 2018

DOI 10.4093/dmj.2018.0055

narrative_reviewCited 118×
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DOI resolved against Crossref · corpus check 2026-06-10

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