Peptide medications that act on the body's appetite and blood sugar hormones, known as the GLP-1 family, are among the best-studied treatments in modern medicine. Three large trials show what they can do.
STEP 1: about 15% weight loss
The STEP 1 trial enrolled 1,961 adults with obesity, or overweight plus a weight-related health problem, who did not have diabetes. Everyone also received lifestyle support. One group added a weekly GLP-1 medication; the other added a placebo.
After 68 weeks:
- Average weight loss was 14.9% with the medication vs 2.4% with placebo.
- 69.1% of people on the medication lost at least 10% of their weight, compared with 12.0% on placebo.
- About half (50.5%) lost at least 15%, compared with 4.9% on placebo.
SURMOUNT-1: up to about 21%
SURMOUNT-1 tested a weekly medication that acts on two appetite hormones (GLP-1 and GIP) in 2,539 adults with obesity or overweight.
After 72 weeks, average weight loss was 15.0%, 19.5% and 20.9% at the three doses tested, compared with 3.1% with placebo.
SELECT: fewer heart attacks and strokes
Weight loss is one thing. The SELECT trial asked whether a GLP-1 medication also protects the heart. It enrolled 17,604 adults with existing heart disease and overweight or obesity, but no diabetes.
Over an average of about 40 months, heart attack, stroke or cardiovascular death occurred in 6.5% of people on the medication vs 8.0% on placebo, a 20% lower risk. People on the medication lost an average of 9.4% of their body weight.
The trade-offs
The most common side effects in these trials were digestive, such as nausea, diarrhea and constipation, especially while the dose was increased. These medicines work while you take them, so they need a long-term plan, regular check-ins and attention to keeping muscle through strength training and enough protein.
Is it right for you?
Not everyone needs medication, and not everyone is a candidate. A full assessment and blood panel come first: blood sugar, cholesterol, liver and kidney function, and hormones such as testosterone, which can be low in men with excess weight.
Read about peptide therapy at Ora, or see what our at-home blood panel checks.
Sources
- Wilding JPH, et al. (STEP 1). N Engl J Med. 2021;384:989–1002. doi.org/10.1056/NEJMoa2032183
- Jastreboff AM, et al. (SURMOUNT-1). N Engl J Med. 2022;387:205–216. doi.org/10.1056/NEJMoa2206038
- Lincoff AM, et al. (SELECT). N Engl J Med. 2023. doi.org/10.1056/NEJMoa2307563
