The best GLP-1 supplement for weight loss? What the evidence says

Since GLP-1 medicines such as Ozempic, Wegovy, Mounjaro and Zepbound became famous, the supplement aisle has filled with products carrying "GLP-1" on the label. The name suggests they do something similar for less money and without a prescription. The evidence says otherwise, but there is one food that genuinely nudges your own GLP-1 up.

What GLP-1 is

GLP-1 (glucagon-like peptide-1) is a hormone your gut releases after you eat. It helps regulate blood sugar and signals fullness. GLP-1 medicines mimic this hormone at much higher, longer-lasting levels, which is why they reduce appetite so strongly.

How big the gap is

In STEP 1, adults with overweight or obesity taking semaglutide for 68 weeks lost 14.9 percent of their body weight on average, about 15 kg, against 2.4 percent with placebo.³ Berberine, the supplement most often called nature's Ozempic, reduced body weight by 0.88 kg and BMI by about half a point on average across 23 studies.⁴ That is a real effect, and a very small one.

Why the label can say GLP-1

Dietary supplements do not need FDA approval before they are sold. Under US law, the FDA cannot approve supplements before marketing, and it generally does not approve their label claims either.² A product can be named after GLP-1 without ever having been tested for weight loss.

A second, more dangerous group of products claims to contain the actual drugs, semaglutide or tirzepatide, sold online without a prescription or as drops and sprays. The FDA warns that unapproved versions of GLP-1 drugs do not go through its review for safety, effectiveness and quality, and advises patients to get a prescription from their doctor and fill it at a state-licensed pharmacy.¹

The food that raises your own GLP-1

Protein is the best studied way to raise GLP-1 with food. In a crossover study, the same volunteers ate three breakfasts with equal calories, one high in protein, one high in fat and one high in carbohydrate. GLP-1 and PYY, another fullness hormone, were highest after the high protein breakfast, and GLP-1 stayed higher throughout the four hours.⁵

Two honest caveats. The study was small, eight people. And in that study the higher hormones did not change how much people ate at the next meal. That fits the wider evidence: protein makes meals more satisfying, but its effect on how much you eat later is less consistent.⁶

So protein is not a natural Ozempic either. What it does reliably is help during weight loss: in a meta-analysis of 24 trials, higher protein diets with the same calories led to slightly more fat loss and kept about 0.4 kg more lean mass.⁷ Protein and hunger goes into the fullness research.

If you are taking a GLP-1 medicine

Muscle is the thing to watch. GLP-1 medicines reduce appetite so much that eating enough protein becomes harder, and part of the weight lost can be muscle. Protein and muscle loss on GLP-1 medications explains how much protein to aim for, and what to eat on a GLP-1 turns it into meals.

Protein Buddy was built with this in mind. It works out a daily protein target from a short quiz on your weight, age, activity, goal and whether you take a GLP-1, and Home shows how many grams are left today as you log. Typing meals in by hand is free with no limit, which helps on days when you can only manage small portions.

For supplements that can genuinely help while on a GLP-1 medicine, see supplements to take on a GLP-1, and for pills sold for weight loss in midlife, menopause weight loss pills.

Before you buy anything

Three checks before spending money on a GLP-1 supplement:

1. Has this product, not just an ingredient, been tested for weight loss in people?
2. Does it claim to contain semaglutide or tirzepatide without a prescription? If so, avoid it.
3. Have you checked your protein? A higher protein diet is cheaper and has better evidence during weight loss.

If you are thinking about a GLP-1 medicine, the right first step is your doctor, who can tell you whether it suits you. Before starting a GLP-1 lists what to put in place first. If you take any supplement, including berberine, tell your doctor or pharmacist, because supplements can interfere with prescription medicines.