Sturdy
How much protein should you eat on a GLP-1?
In May 2025 four medical societies, the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association and The Obesity Society, published a joint advisory on nutrition for people taking GLP-1 medications such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound). It notes that targets of 1.2 to 1.6 g of protein per kilogram per day have been proposed during active weight loss, above the general adult recommendation of 0.8 g per kg.
The advisory also points out that using actual body weight can significantly overestimate protein needs for people with obesity, and that adjusted or ideal body weight, or fat-free mass, may be better. It offers a simpler alternative too: an absolute target of 80 to 120 g a day.
How this calculator works
- It estimates your ideal body weight from your height and sex with the Devine formula.
- If your weight is more than 20% above that, it uses an adjusted body weight: ideal weight plus 40% of the difference. Otherwise it uses your current weight.
- It multiplies that weight by 1.2 and 1.6 to get your daily range, rounded to the nearest 5 g, and never lets the top reach 2 g per kg, which the advisory says to avoid long term.
- It splits your chosen goal across the times you eat, so each meal has a number you can actually hit.
Why protein alone is not enough
GLP-1 medications reduce appetite, and part of the weight people lose can be muscle. The advisory is clear that protein is a priority for keeping muscle and bone, but also that more protein on its own is likely not enough. It recommends regular strength training at least three times a week. Aerobic exercise alone does less to protect lean mass during fast weight loss.
Making the target easier when you are not hungry
- Eat the protein first. The advisory suggests eating protein-rich foods first in a meal so you get them in before you feel full.
- Spread it out. Four or five smaller servings are easier than three big ones. Switch the tool to 4 or 5 and it adds a snack.
- Lean on dense foods. Greek yogurt, cottage cheese, fish and chicken give a lot of protein for a small portion.
- Keep drinking. The advisory warns that dehydration from nausea, vomiting or diarrhea can hurt the kidneys.
Protein in common foods
Approximate values for typical portions, based on USDA FoodData Central. Brands vary, so check labels where you have them.
| Food | Protein |
|---|---|
| Chicken breast, 3 oz cooked | 26 g |
| Greek yogurt, 6 oz plain | 17 g |
| Cottage cheese, ½ cup | 13 g |
| Egg, large | 6 g |
| Tuna, 3 oz canned | 20 g |
| Salmon, 3 oz cooked | 22 g |
| Shrimp, 3 oz cooked | 20 g |
| Lean beef, 3 oz cooked | 22 g |
| Firm tofu, 3 oz | 14 g |
| Lentils, ½ cup cooked | 9 g |
| Edamame, ½ cup | 9 g |
| Milk, 1 cup | 8 g |
| String cheese, 1 stick | 7 g |
| Turkey slices, 2 oz | 10 g |
| Peanut butter, 2 tbsp | 7 g |
| Protein shake (check label) | 20 g |
