GLP-1 medications, such as Ozempic and Wegovy, work by mimicking GLP-1, a natural hormone in your body. In addition to helping control blood sugar after meals, these medications also reduce your appetite and how quickly your stomach empties. The result? You stay fuller longer, cravings are reduced, and your blood sugar levels are likely to drop after you eat.
Their popularity has increased in recent years. In the 2025 KFF Health Tracking Poll, 1 in 8 US adults reported taking a GLP-1 medication (also known as a glucagon-like peptide-1 receptor agonist). Originally approved to manage blood sugar levels in people with type 2 diabetes, these drugs have become widely used for weight loss.
Because GLP-1 medications change how your gut and metabolism function, it’s wise to closely watch your supplement routine. While most supplements seem harmless, some can interact with these medications in ways that can lead to unwanted side effects—think gastrointestinal (GI) problems, nutrient deficiencies or dangerously low blood sugar.
To help sort out which supplements don’t interact well with GLP-1 medications, we asked experts what to skip so you can stay safe and feel your best.
1. Fat burner and stimulant
If you are already on a GLP-1 medication, adding an over-the-counter fat burner is not recommended.
“One supplement I recommend avoiding on GLP-1 are fat-burning products or stimulants. You’ll also see these marketed as ‘thermogenics’ or ‘metabolism boosters,'” says Ana Reisdorf, MS, RD, dietitian and founder of GLP-1 Hub. “It often contains ingredients such as caffeine, green tea extract, guarana, yohimbine or synephrine (bitter orange).”
Fat burners are popular over-the-counter pills that promise to boost metabolism and accelerate weight loss — or provide a quick energy boost before a workout.
But combining them with GLP-1 drugs is not a good idea. “GLP-1 affects appetite, digestion and how quickly food moves through the gut. Adding stimulants on top of that can worsen GI side effects, especially nausea,” says Reisdorf.
They can suppress appetite even further, making it harder to meet protein and nutrient needs—a challenge these drugs already pose.
2. Magnesium oxide
Magnesium is an essential mineral that supports muscle function, sleep and nerve health. Magnesium oxide, in particular, is a common and inexpensive form that is often used to relieve occasional constipation.
However, this may not be the best choice if you are on GLP-1.
“The bioavailability of magnesium oxide is poor to begin with, and only 1% to 2% is absorbed in healthy individuals,” says Daniel Ghiam, MD, a board-certified physician at MedPodLA.com. “GLP-1 drugs alter gut motility and transit time, making absorption more unpredictable. Anything not absorbed draws water into the colon, and for patients already managing GI symptoms, that can turn things from manageable to miserable.”
In other words, poor absorption combined with slow digestion can lead to bloating, cramping or diarrhea.
If you’re supplementing magnesium, consider forms like magnesium glycinate or magnesium L-threonate, which are more easily absorbed. A healthcare provider can help you choose the right option.
3. Berberine
Berberine is a plant compound that has gained popularity on social media as a “natural” way to support blood sugar and metabolic health. Some research suggests that it can help improve cholesterol, reduce insulin resistance and support weight management.
But combining it with GLP-1 drugs can be risky.
“Berberine, along with GLP-1, can have a compounding effect on lowering blood sugar, which can lead to hypoglycemia,” says Grace Engels, RD, of Grace Engels Nutrition. “Combine that with appetite suppression, and you’re dealing with dizziness, fainting, or worse in severe cases.”
4. Alpha-lipoic acid
Alpha-lipoic acid (ALA) is an antioxidant found naturally in spinach, broccoli and yeast. As a supplement, it is often used to manage nerve pain, reduce inflammation and lower blood sugar.
Like berberine, ALA can reduce insulin sensitivity and blood glucose. Since GLP-1 drugs already do that, adding ALA can increase your risk of hypoglycemia, which can make you shaky, sweaty, and weak.
5. Viscous fiber supplement
Viscous fiber supplements such as psyllium and glucomannan are often used to aid digestion, lower cholesterol or increase fullness. They work by absorbing water and slowing digestion by forming a gel-like substance in the intestines.
But with GLP-1 drugs, that effect can be reversed.
“GLP-1 receptor agonists already delay gastric emptying and increase satiety, so further delayed digestion can increase fullness and decrease overall tolerance,” says Kerry Luati, MS, RD, LDN, CDE, director of women’s health clinical operations at LifeMD.
In short, you may feel overly full—even uncomfortably so. If you’re already dealing with nausea or bloating, these supplements can make things worse.
Best supplements to take with GLP-1 medications
While some supplements are best avoided, others can help manage common side effects. Because GLP-1 drugs suppress appetite, there is a high risk of nutrient deficiencies.
Here are some options to discuss with your healthcare provider.
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Protein Powder: Eating less can make it harder to hit protein goals. A high-quality protein powder can help preserve lean muscle mass during weight loss.
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Vitamin B12: It’s normal to feel tired when you’re in a calorie deficit. A B12 supplement can help fill in any gaps and support energy levels and nerve health.
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Vitamin D: Most people don’t get enough. It plays an important role in bone health, which is especially important during rapid weight loss.
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Electrolytes: If you’re experiencing nausea or vomiting, dehydration can quickly set in. Sugar-free electrolyte packets can help maintain fluid balance.
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Multivitamins: If you’re concerned about depleting key nutrients while eating less, a multivitamin can provide some added peace of mind.
Other nutritional tips while taking GLP-1 medications
Supplements are only part of the picture. Your daily habits are also important. Here are some simple ways to minimize side effects and support a balanced diet.
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Eat less food: Because gastric emptying is delayed, large meals can cause bloating and nausea.
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Make hydration a priority: Hunger suppression can make it easy to forget to drink water. Keep a reusable water bottle within reach.
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Focus on fiber: Constipation is common. Stick with lighter options like chia seeds or cooked vegetables.
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Chew well: Digestion begins in the mouth. The burden on the stomach can be reduced by breaking down the food properly.
FAQs
Is magnesium okay to take with GLP-1 medication?
Yes – but type is important. Magnesium oxide is more likely to cause digestive problems, while other forms are better tolerated.
“If a patient really needs magnesium—and many calorie-restricted patients do—they should try magnesium glycinate. Supplement form and bioavailability are more important than people realize,” says Ghiam.
Magnesium glycinate is well absorbed and has less of a laxative effect.
Should I take probiotics while on GLP-1 medication?
Probiotics can help, especially if you’re dealing with bloating or constipation. The key is to choose research-backed strains that match your symptoms and overall gut health goals. When in doubt, talk to a doctor or other healthcare professional to find the best probiotic supplement for your needs.
Meet our experts:
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Kerry Luati, MS, RD, LDN, CDE, Director of Women’s Health Clinical Operations at LifeMD.
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Grace Engels, Registered Dietitian in Grace Engels Nutrition.
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Daniel Ghiam, MD, board-certified physician at MedPodLA.com.
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Ana Reisdorf, MS, RD, Dietitian and Founder of GLP-1 Hub
Our health content is for informational purposes only and does not constitute professional medical advice. Consult a medical professional with questions about your health.
