5 supplements to avoid if you’re taking GLP-1 drugs, according to experts

GLP-1 drugs such as Ozempic and Wegovy, Work by mimicking GLP-1It is a natural hormone in your body. In addition to helping regulate blood sugar after meals, these medications also suppress your appetite and slow the rate at which your stomach empties. Conclusion? You stay full longer, your desire to eat decreases, and your blood sugar is less likely to rise after a meal.

Their popularity has increased in recent years. In the 2025 KFF Health Follow-up Survey, 1 in 8 US adults reported taking a GLP-1 medication (also known as a glucagon-like peptide-1 receptor agonist). Originally approved managing blood sugar levels These medications have since become widely used for weight loss in people with type 2 diabetes.

Since GLP-1 drugs alter how your gut and metabolism work, it’s wise to take a closer look at your supplement routine. While most supplements seem harmless, some may interact with these medications to cause unwanted side effects; think gastrointestinal (GI) issues, nutrient deficiencies, or even dangerously low blood sugar, for example.

To help determine which supplements don’t interact well with GLP-1 medications, we asked experts what you should skip so you can stay safe and feel your best.

1. Fat burners and stimulants

If you are already taking a GLP-1 medication, adding an over-the-counter fat burner is not recommended.

“One of the supplements I recommend avoiding on GLP-1 is fat-burning products or products containing stimulants. You’ll also find these marketed as ‘thermogenic’ or ‘metabolism boosters,'” he says Ana ReisdorfMS, RD, dietitian and founder of GLP-1 Hub. “These often contain 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 exercise.

But combining them with GLP-1 drugs is not a good idea. “GLP-1s already affect appetite, digestion, and how quickly food moves through the stomach. Adding stimulants on top of that can worsen GI side effects, especially nausea,” says Reisdorf.

They can too suppress appetite What’s more, it makes it difficult to meet protein and nutrient needs; a challenge already posed by these drugs.

2. Magnesium oxide

Magnesium is an important mineral that supports muscle function, sleep and nerve health. Magnesium oxide, in particular, is a common and inexpensive form often used to relieve occasional constipation.

However, if you are using GLP-1, this may not be the best choice.

“Magnesium oxide has poor initial bioavailability and in fact only 1% to 2% is absorbed in healthy individuals,” he says. Daniel GhiyamMD, a board-certified physician at MedPodLA.com. “GLP-1 drugs alter intestinal motility and transit time, which makes absorption even more unpredictable. Anything that isn’t absorbed draws water into the colon, and for patients already managing GI symptoms, this can take things from manageable to awful.”

In other words, poor absorption combined with slow digestion can lead to bloating, cramps, or diarrhea.

If you’re supplementing with magnesium, consider more easily absorbed forms such as magnesium glycinate or magnesium L-threonate. A healthcare professional can help you choose the right option.

3. Berberine

Berberine It is a plant compound that has gained popularity on social media as a “natural” way to support blood sugar and metabolic health. Some research It suggests that it may help improve cholesterol, reduce insulin resistance and support weight management.

But pairing it with a GLP-1 drug could be risky.

“Berberine, along with GLP-1, may have a combined effect on lowering blood sugar, leading to hypoglycemia,” he says. Grace EngelsFrom Grace Engels Nutrition, RD. “If you combine this with appetite suppression, you could be looking at dizziness, fainting, or worse in severe cases.”

4. Alpha-lipoic acid

Alpha-lipoic acid (ALA) It is an antioxidant found naturally in foods such as spinach, broccoli and yeast. As a supplement, it is often used to manage nerve pain, reduce inflammation, and lower blood sugar.

Like berberine, ALA may increase insulin sensitivity and lower blood sugar. Since GLP-1 drugs already do this job, adding ALA can increase your risk of hypoglycemia, which can leave you shaky, sweaty, and weak.

5. Viscose fiber supplements

Viscous fiber supplements such as psyllium and glucomannan are often used to support digestion, lower cholesterol, or increase satiety. They work by absorbing water and forming a gel-like substance in the intestine, slowing down digestion.

However, with a GLP-1 drug, this effect may backfire.

“GLP-1 receptor agonists already delay gastric emptying and increase satiety, so layering in supplements that further slow digestion may increase satiety and reduce overall tolerance,” he says Kerri LouatiMS, RD, LDN, CDE, director of clinical operations for women’s health at LifeMD.

In short, you may feel extremely full, even uncomfortable. If you’re already dealing with nausea or bloating, these supplements may make it worse.

Best supplements to take with GLP-1 medications

While some supplements are best avoided, others may help manage common side effects. Because GLP-1 drugs suppress appetite, the risk of nutrient deficiencies is higher.

Here are a few options to discuss with your healthcare provider.

• Protein powder: Eating less may make hitting harder protein targets. A high-quality protein powder can help preserve lean muscle mass during weight loss.

• Vitamin B12: It’s common to feel tired when you’re in a calorie deficit. B12 supplements can help fill any gaps and support energy levels and nerve health.

• Vitamin D: Many people don’t get enough. It plays an important role in bone health, which is especially important during periods of rapid weight loss.

• Electrolytes: Dehydration can occur quickly if you are experiencing nausea or vomiting. Sugar-free electrolyte packs can help maintain fluid balance.

• Multivitamin: If you’re worried about running out of essential nutrients while eating less, a multivitamin may provide some additional 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 a few simple ways to help minimize side effects and support a balanced diet.

• Eat smaller meals: Large meals can cause bloating and nausea because stomach emptying is slower.

• Prioritize hydration: Appetite suppression may make it easier to forget to drink water. Keep a reusable water bottle handy.

• Focus on fiber: Constipation is common. Stick to softer options like chia seeds or cooked vegetables.

• Chew thoroughly: Digestion begins in the mouth. Breaking down food well can ease the burden on your stomach.

FAQ

Is it appropriate to take magnesium with a GLP-1 medication?

Yes, but the genre matters. Magnesium oxide is more likely to cause digestive problems, while other forms are better tolerated.

“If a patient really needs magnesium, and most calorie-restricted patients do, they should try magnesium glycinate. Supplement form and bioavailability are more important than people think,” says Ghiyam.

Magnesium glycinate is well absorbed and is less likely to cause a laxative effect.

Should I take probiotics while using GLP-1 medication?

A probiotic may be helpful, 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:

• Kerri Louati, MS, RD, LDN, CDE, director of clinical operations for women’s health at LifeMD.

• Grace Engels, Grace is a registered dietitian at Engels Nutrition.

• Daniel Ghiyam, MD, board-certified physician at MedPodLA.com.

• 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 any questions you have about your health.