Weight lossNEJM · 2021
STEP 1
Weekly semaglutide in adults with overweight or obesity
14.9%average body weight lost at 68 weeks, vs 2.4% on placebo
Adults without diabetes took semaglutide 2.4 mg weekly alongside diet and activity support. Most lost a clinically meaningful amount of weight.
What it means for you: Semaglutide can produce substantial weight loss when combined with lifestyle changes.
Weight lossNEJM · 2022
SURMOUNT-1
Weekly tirzepatide for the treatment of obesity
20.9%average body weight lost at 72 weeks on the highest dose, vs 3.1% on placebo
Adults without diabetes took tirzepatide at 5, 10 or 15 mg. Weight loss increased with dose: 15.0%, 19.5% and 20.9%.
What it means for you: Tirzepatide is one of the most effective weight loss medications studied to date.
Weight lossNEJM · 2025
SURMOUNT-5
Tirzepatide compared with semaglutide, head to head
20.2%average weight lost on tirzepatide at 72 weeks, vs 13.7% on semaglutide
The first large trial comparing the two directly in adults with obesity and no diabetes.
What it means for you: Both work. Tirzepatide led to more weight loss on average, which can help you and your provider choose.
Heart healthNEJM · 2023
SELECT
Semaglutide and heart outcomes in people with obesity
20%lower risk of heart attack, stroke or cardiovascular death
Adults with existing heart disease and overweight or obesity, but no diabetes, took semaglutide 2.4 mg or placebo for an average of about 3 years.
What it means for you: The benefits of GLP-1 treatment may go beyond the scale for people with heart disease.
Keeping weight offJAMA · 2021
STEP 4
What happens when you stop semaglutide
6.9%body weight regained in those switched to placebo, while those who continued lost 7.9% more
After 20 weeks on semaglutide, participants either continued or switched to placebo for 48 weeks.
What it means for you: Weight loss is easier to maintain when you stay on treatment.
Keeping weight offDiabetes, Obesity and Metabolism · 2022
STEP 1 extension
Weight and health one year after stopping semaglutide
2/3of lost weight regained on average within a year of stopping
Participants from STEP 1 were followed after treatment ended. Health markers like blood pressure also moved back toward where they started.
What it means for you: Planning for maintenance matters as much as the initial weight loss.
LongevityNature Communications · 2018
NR in older adults
Nicotinamide riboside raises NAD+ levels
~60%increase in blood NAD+ levels in a small 6-week crossover trial
Healthy middle-aged and older adults took nicotinamide riboside, an NAD+ precursor. It was well tolerated and raised NAD+ in the blood.
What it means for you: NAD+ support is an active area of research. Larger studies are still needed on long-term benefits.