Research

Energy balance

Smoking cessation increases the short-term risk of type 2 diabetes, but this risk is directly proportional to post-cessation weight gain and does not mitigate the long-term reduction in cardiovascular and all-cause mortality.

Quitting smoking is the single most important step for longevity, regardless of what happens to your weight. While you might gain weight and see a temporary spike in diabetes risk (especially if you gain >10kg), the reduction in your risk of dying from heart disease or other causes is massive and sustained. Do not let the fear of weight gain prevent you from quitting.

StrongQualifiesHIGH confidence
The temporary increase in the risk of type 2 diabetes was directly proportional to weight gain, and the risk was not increased among quitters without weight gain... quitters did not have a temporary increase in mortality, regardless of weight change after quitting.
Yang Hu et al. · New England Journal of Medicine · 2018

Why this rating

Large prospective cohort studies (NHS, NHS II, HPFS) with long follow-up and rigorous adjustment for confounders.

Source

Smoking Cessation, Weight Change, Type 2 Diabetes, and Mortality

Yang Hu et al. · New England Journal of Medicine · 2018

DOI 10.1056/nejmoa1803626

cohort · n=170723Cited 252×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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