Research
Hormonal
Quitting smoking is associated with significant weight gain (5.17 lb over 4 years), while continued smoking is associated with less weight gain (-0.70 lb).
If you quit smoking, expect some weight gain (average 5.17 lb over 4 years). This is a common side effect of cessation. Focus on healthy dietary changes and increased physical activity to manage this. The health benefits of quitting smoking far outweigh the risks of weight gain.
GoodQualifiesHIGH confidence
As compared with persons who never smoked, those who had quit smoking within the previous 4 years had a weight gain of 5.17 lb... Continued smoking was inversely associated with weight gain (−0.70 lb), a finding that may have been related to undiagnosed chronic disease.
Why this rating
Large cohorts, but potential confounding from undiagnosed disease in smokers.
Source
Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men
Dariush Mozaffarian et al. · New England Journal of Medicine · 2011
DOI 10.1056/nejmoa1014296
cohort · n=120877Cited 2,525×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- Increasing daily servings of potato chips, potatoes, sugar-sweetened beverages, unprocessed red meats, and processed meats is independently associated with greater long-term weight gain, whereas increasing servings of vegetables, whole grains, fruits, nuts, and yogurt is associated with less weight gain.Strong
- Increases in physical activity are associated with less long-term weight gain, whereas absolute levels of physical activity are not associated with weight change.Strong
- Sleep duration has a U-shaped association with weight gain, with greater weight gain occurring with less than 6 hours or more than 8 hours of sleep per night.Good
Related findings · Hormonal
- Initial treatment for type 2 diabetes should be a combination of metformin and either an SGLT-2 inhibitor or a GLP-1 receptor agonist to achieve cardiorenal protection, rather than monotherapy or older agents like sulfonylureas.Strong
- For patients with specific monogenic obesity syndromes (leptin deficiency, POMC/PCSK1/LEPR mutations), targeted pharmacotherapy (recombinant leptin or setmelanotide) is highly effective and should be prioritized, unlike in polygenic obesity.Strong
- Continued weekly administration of 2.4 mg subcutaneous semaglutide prevents weight regain and promotes further weight loss in adults with overweight or obesity, whereas switching to placebo results in significant weight regain.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 →