What’s the best GLP-1 diet?

Many people incorrectly believe that GLP-1s are a free pass, where you can eat whatever you want and still lose weight. But the science is clear that this is not the case. Experts recommend that you still pay attention to your food choices when you’re losing weight on a GLP-1 to support your long-term health (a.k.a. the main reason to lose weight!). Here’s what to focus on.

Fiber is so key because it can help reduce constipation, which can be a side effect of GLP-1s. The USDA recommendation is at least 25 grams of fiber a day for women and 38 grams a day for men.

Fiber can come from veggies like kale and Brussels sprouts, fruit like apples and berries, nuts and seeds like almonds and chia seeds, beans, and whole grains. Bonus: These foods also tend to be packed with nutrients, helping you get what you need to be healthy even though you’re eating less due to a reduced appetite.

Learn more about how to handle constipation while on a GLP-1

This is also a good time to prioritize high-protein foods like lean meat and poultry, which are lower in saturated fat, as well as vegetarian options like tofu, lentils, and beans. “It’s important to include ample protein in the diet with each meal, since excessive weight loss may lead to loss of muscle,” says Dr. Robert Kushner, M.D., professor of medicine in endocrinology and medical education at Northwestern University Feinberg School of Medicine in Chicago. Eating more protein — in combination with strength training — can help lessen that muscle loss. Although individual recommendations can vary, 1.0 to 1.2 grams of protein per kg of your current body weight is a good goal for most people.

Learn about why protein is so important when losing weight

Drinking plenty of water is also smart when you’re on a GLP-1. Staying hydrated can help with constipation and can replenish your fluids if you vomit as a side effect of the medication. Dr. Caroline Messer, M.D. — a professor of medicine, endocrinology, diabetes, and bone disease at Icahn School of Medicine at Mount Sinai in New York City — recommends that her patients drink at least 64 ounces of fluid a day.

GLP-1s and fatty foods don’t mix well because fat can make certain side effects worse. The medications slow the emptying of the stomach, but “consuming dietary fat has the same effect,” says Kushner. “So, the combination of the medication along with fatty foods may worsen the problem and increase side effects, such as nausea, vomiting, and heartburn.” Go for the leaner cuts of meat, low-fat dairy, and non-fried options whenever possible.

Learn about what foods to avoid on a GLP-1

It also helps to time your meals strategically. Messer recommends leaving a two-hour window between eating and going to bed to help minimize reflux (another side effect of GLP-1s). She also advises patients to not drink liquids while they’re eating so that they don’t feel too full too quickly.