Bariatric surgeries like gastric bypass are often used for weight loss, but they can also help protect patients from fatal heart attacks, possibly by altering the levels of gut-derived metabolic hormones like GLP-1, leptin, ghrelin, and insulin, which are known to affect heart tissue, or by acting on heart tissue directly. Researchers recently investigated the mechanisms by performing three common bariatric surgeries on non-obese, non-diabetic rats. Ten weeks later, the researchers subjected the rats to simulated heart attacks by restricting and reestablishing their cardiac blood flow. Both Roux-en-Y gastric bypass and sleeve gastrectomy, but not ileal transposition surgery, reduced the size of the damaged area in the heart and the no-reflow area to which blood flow couldn’t be restored. Gastric bypass and sleeve gastrectomy also increased GLP-1 and leptin levels, while sleeve gastrectomy reduced ghrelin levels. In contrast, none of the surgeries affected insulin levels. Although research in humans is needed, the results suggest that certain bariatric surgeries reduce heart attack damage by improving cardiac tolerance to ischemia-reperfusion and reveal specific changes in gut hormone levels that are associated with this cardioprotection, further emphasizing the value of bariatric surgery for more than just weight loss.