- In the STEP 1 trial, people lost about 15 percent of body weight on average over 68 weeks.
- About one in three people lost 20 percent or more.
- Weight loss is slow at first while the dose is increased.
- Protein, strength training and follow-up help results last.
What the research shows
In the STEP 1 trial, adults with obesity or overweight took semaglutide 2.4 mg weekly with lifestyle support. After 68 weeks they lost about 15 percent of their body weight on average. For someone who weighs 220 pounds, that is about 33 pounds. About one in three people lost 20 percent or more, while some lost less.
With the 25 mg Wegovy pill, average weight loss in the OASIS 4 trial was about 14 percent over 64 weeks.
A realistic timeline
- Months 1 to 4: the dose goes up step by step. Hunger drops, but weight loss is gradual.
- Months 4 to 12: the full dose is reached and weight loss is usually fastest.
- After about a year: weight loss slows and levels off. The focus shifts to keeping it off.
What affects your results
- Taking the medicine on schedule and reaching an effective dose
- Eating enough protein and fewer ultra-processed foods
- Strength training to protect muscle
- Sleep and stress
- Other conditions, such as diabetes, which often leads to somewhat less weight loss
- Medicines that cause weight gain
If your results are below what you hoped, it does not mean you failed. Your doctor may adjust the dose, look for hormone causes or consider tirzepatide.
Learn more on our page about Semaglutide in Chicago, or get in touch to request a visit.
Triple board-certified endocrinologist and obesity medicine specialist in Chicago. This article is for general education and is not medical advice.