The Hidden Risks of Ozempic and Other Weight Loss Drugs: What You Need to Know

The new generation of weight loss medications, such as Ozempic (semaglutide), are gaining widespread attention for their impressive results. These drugs appear to reduce cravings, increase satiety, blunt blood sugar spikes after meals, and even improve how the body metabolises and stores fat. For individuals struggling with weight loss or insulin resistance, they can seem like a game-changer.

But while the benefits are compelling, it's important to take a closer look at some of the less-discussed risks—especially when it comes to muscle loss and gut health.

Muscle Loss and Long-Term Body Composition

One of the most concerning aspects of these medications is their impact on body composition. Research shows that people on GLP-1 medications like Ozempic can lose significantly more lean muscle mass compared to those who lose weight naturally. In some studies, up to 30-40% of the total weight lost comes from muscle rather than fat.

When the drug is discontinued, many people experience rapid weight regain. Unfortunately, the regained weight tends to be predominantly fat, not muscle, leading to a net loss in muscle mass and a higher overall body fat percentage. This shift can negatively impact metabolic health, making it harder to maintain a healthy weight and stable blood sugar levels in the future.

What are the impacts on the microbiome?

Another emerging issue is the drug’s effect on the digestive system. One of the ways these medications work is by slowing gastric emptying, meaning food stays in the stomach and intestines longer. While this contributes to the feeling of fullness, it may also disrupt the delicate balance of the gut microbiome.

Prolonged digestion can promote the growth of sulphur-producing bacteria such as Desulfovibrio piger — a species commonly detected on comprehensive stool tests. Overgrowth of these bacteria can lead to unpleasant digestive symptoms, including gas and "eggy" burps, due to increased hydrogen sulphide production.

High levels of sulphur gas are not only uncomfortable but can also be inflammatory for the gut lining. In some cases, they have been linked to digestive conditions such as inflammatory bowel disease (IBD).

Final Thoughts

While medications like Ozempic can offer powerful short-term benefits, they are not without risks. For anyone considering or currently using these drugs, it is essential to support the body with:

• Adequate protein intake to preserve muscle

• Resistance training to maintain lean mass

• Gut-supportive nutrition, including fibre and polyphenols and probiotics or PHGG to nurture a healthy microbiome

As with any intervention, the most sustainable results come from a holistic, personalised approach. If you’re thinking about using a weight loss medication or are concerned about its effects on your gut and metabolism, work with a qualified practitioner who can guide you through the safest and most supportive strategies for long-term health.

Kate Osborne, Nutritional Therapist | Specialising in Women's Hormonal and Gut Health