A once-weekly injectable recently approved to treat type 2 diabetes, called tirzepatide (sold as Mounjaro), may also be effective for weight loss in people with obesity. In a study, overweight or obese participants without type 2 diabetes who took tirzepatide lost an average of nearly 21% of their body weight at the highest dose. The trial included 2,539 adults with an average weight of 231 pounds and a BMI of 38. Participants received either a placebo or one of three doses of tirzepatide (5 mg, 10 mg, or 15 mg) for 72 weeks. At the highest dose, participants lost about 52 pounds on average. Most side effects were mild to moderate, mainly gastrointestinal issues like nausea, diarrhea, and constipation. The study suggests tirzepatide could be a significant step forward in obesity treatment, potentially offering an alternative to bariatric surgery. However, its price may be a concern, as similar drugs cost over $1,300 a month. More head-to-head trials are needed to confirm its efficacy compared to other treatments.