Another great reason to lose weight if you are really overweight (let's be honest, the term is "obese") is a lower risk of two types of skin cancer: squamous cell carcinoma and melanoma. Obesity is considered a cancer risk, that is, it increases the risk of cancer, and after bariatric surgery there is a lower risk of cancer.
A long-running study in Sweden (Swedish Obese Subjects study) followed 2 groups of obese individuals for 18 years - 1 group received bariatric surgery (2007 persons) and the other group didn't (2040 persons). They found that the group who had received bariatric surgery, along with a large weight loss, had a significantly lower risk of getting squamous cell carcinoma and melanoma than the group who received conventional "obesity treatment" (such as advice on losing weight).
How much weight did they lose after the surgery? After 2 years the average weight loss in the surgery group was 63.27 pounds (28.7 kg), which leveled off to 47.62 lbs (47.62 kg) by the 15 year follow-up visit. The weight changes in the non-surgery (control) group was small and never exceeded 6.61 pounds in gains or losses.
The researchers give a number of reasons why a large weight loss may be contributing to reduced risk of skin cancer, including leptin uptake changes, lower chronic systemic inflammation, and changes in gut microbes. In summary, they found a 42% lower risk for both forms of skin cancer combined, and 57% lower risk of malignant melanoma in the surgery group (as compared to the non-surgery group).
BOTTOM LINE: If you are really overweight, then try, try, try to lose a big chunk of weight. Your body will thank you in many ways. Not just lower risk of some cancers (including breast cancer), lower risk of diabetes, increased chance of diabetes reversal, lower risk of dementia, lower chronic systemic inflammation, better sperm quality, and on and on.