Dr Max: Weight-loss drugs are amazing. But we'll always need healthy nutrition and lifestyle

Everywhere you turn, these days you’ll see a headline about weight loss jabs such as Ozempic, Wegovy, and Mounjaro. Suddenly, we’re all familiar with a previously little-known medical acronym: GLP-1. But behind the headlines and the hype, there’s something genuinely fascinating going on. And the real story is in biology.

What is GLP-1?

GLP-1 isn’t artificial, or new – it’s a hormone your body already makes. Every time you eat, your gut releases GLP-1, glucagon-like peptide-1, and its role is to help regulate how your body handles food. It signals to your brain that you’ve had enough, helps control blood sugar by stimulating insulin, and slows down how quickly food leaves your stomach.

In other words, GLP-1 is part of your natural appetite and metabolic control system, and has been quietly working in the background your entire life.

How weight-loss drugs amplify the GLP-1 signal

Weight-loss drugs are enhanced versions of this natural hormone. The GLP-1 that your body produces only lasts a few minutes before it’s broken down. The pharmaceutical versions have been engineered to last much longer, sometimes days or even a full week. That changes everything, because instead of a short signal after a meal, you get a continuous message to the brain that you are full and don’t need to eat. 

As a result, people eat less, often much less, and weight comes down. But it’s not just about appetite. These drugs also improve blood sugar control, which is why they were originally developed for type 2 diabetes. They influence insulin, slow digestion, and shift how the body handles energy.

These drugs show how our weight is deeply rooted in our biology

Recently, newer versions of the drug have taken this even further. Some don’t just target GLP-1, but also other hormones such as GIP, another gut-derived signal involved in metabolic regulation. Mounjaro is one of these dual-action drugs, working on both GLP-1 and GIP. 

There are now even triple-action drugs in development that target GLP-1, GIP and glucagon at the same time. This is multi-hormone control of metabolism. It’s very clever science, but it also reinforces an important point: weight regulation is not just about willpower, it’s deeply rooted in biology.

For people struggling with obesity or type 2 diabetes, these drugs can be transformative. We are seeing levels of weight loss that, until recently, were only achievable with surgery. They can improve blood glucose control, reduce cardiovascular risk, and in some cases lower the risk of major health events. From a clinical perspective, they are one of the most important advances we’ve seen in metabolic health for many years.

The trade-off: Eat a lot less and you may lose healthy nutrients, too

But as with any powerful intervention, there are trade-offs, including the basic issue of nutrition.

When people lose weight quickly, they don’t just lose fat, they also lose muscle as well. That matters, particularly as we get older, because muscle is essential for metabolic health, strength, balance, and long-term resilience. 

These drugs work by suppressing appetite, but if you eat significantly less, you may also take in fewer healthy nutrients, including important vitamins and minerals. There is now growing concern around low protein intake and micronutrient deficiencies in people using these medications, and in some cases even signs of malnutrition.

There are also side effects: digestive issues such as nausea, often experienced at the start. Rare complications are also being monitored, such as potential links to vision problems. As with any medication used at scale, new issues tend to emerge over time, and it is important that these are carefully studied.

What happens when you come off a weight-loss drug?

What happens when the drug is stopped? For many people, the weight returns. This isn’t a lack of discipline; it’s simply biology reasserting itself. Once the drugs are removed, your appetite and metabolic signals return to their previous state. These drugs act more like a long-term management strategy rather than a short-term solution.

Weight-loss medications are now moving from injections to pills. Oral versions already exist, and more are coming. This matters because a simple daily pill is far more accessible and acceptable to a wider population. As that happens, use is likely to expand even further, and we may only be at the beginning of this story.

Nutrition and lifestyle will always be the fundamentals of health

My own view is that GLP-1 drugs are genuinely impressive and represent a major step forward in our understanding of metabolism. They highlight that appetite is not simply about willpower, but is regulated by powerful biological systems that can be influenced. But they do not replace the fundamentals of health.

The body still requires adequate nutrition, sufficient protein, maintained muscle mass, and a lifestyle that supports long-term metabolic resilience. These drugs may help people lose weight and improve metabolic health, but they do not change the underlying biology that sustains us.

Dr Max Gowland, PhD, is the founder of Prime Fifty.