Weight loss can be highly challenging, making everyday life more difficult and also very isolating for individuals. There is a lot of stigma surrounding weight gain, and people's struggles can often be overlooked and misunderstood. 

Weight gain has many underlying causes and is more complex than most people would realise. Obesity has lasting impacts on people’s health. It is the cause of many serious underlying health conditions, such as heart attacks, strokes, diabetes, cancers, neurological disorders, chronic respiratory diseases, and digestive disorders.¹ Obesity is often caused by a range of factors, such as genetics, emotional stress, and long-term habits and lifestyle choices that are difficult to change. 

In recent years, there has been an increase in popularity for a specific type of drug, called GLP-1s. Initially, they were approved for treating type 2 diabetes as they help to regulate blood sugar levels, and now they are being used for weight management due to their effects on digestion and appetite.² 

What are GLP-1s?

GLP-1s are also known as glucagon-like peptide-1 receptor agonists. An agonist simply means it is a substance that binds to a receptor in the body, thereby mimicking the behaviour and action of the natural molecule.

GLP-1 is the natural hormone released from the gut after eating. It stimulates the release of insulin, and it suppresses the release of glucagon.³ GLP-1 is released in the gut in response to food intake and travels through the blood to the pancreas, where it stimulates the release of insulin, which lowers blood sugar levels. 

The role of insulin

Insulin lowers blood sugar levels, making the glucose present in the bloodstream enter cells to be stored or used for energy. People with type 2 diabetes either cannot produce enough insulin or their bodies become resistant to it. This means the cells do not react to insulin molecules as they normally would, so sugar remains in the bloodstream and is not taken into the body's cells for use or storage. This is a severe condition and can cause many other health problems, which is why it is important to maintain healthy blood sugar levels.³

Too much or too little sugar in the blood can be harmful. too low and people cannot function normally, too high and we see complications such as damage to cells (blood vessels, nerves, kidneys, and eyes), and in the long term, heart problems, type 2 diabetes, and strokes.⁴

What do GLP-1s do?

These drugs, which mimic the GLP-1 hormone, have multiple effects on the body. GLP-1s not only cause a reduction in blood sugar levels, but they also have effects on appetite and gastric emptying. GLP-1s delay gastric emptying, which means food is kept in the stomach for longer, leading to an increased feeling of satiety and decreased appetite.⁵ 

Receptors for this hormone are also found in the brain and are involved in neural pathways which control a person's appetite, so an increase of activity to these receptors in the brain can lead a person to believe they are full and have a loss of appetite, even if they have hardly eaten. This is because they are mimicking the effects felt after eating.⁶ 

These are two of the main reasons why GLP-1s can facilitate weight loss.

Popular GLP-1 drugs 

Here are some of the approved GLP-1 agonist drugs and their more common brand names, which you may recognise:

• Semaglutide injection (Ozempic and Wegovy)
• Semaglutide tablets (Rybelsus)
• Tirzepatide injection (Mounjaro)
• Liraglutide (Victoza) 

Healthcare prescribers can prescribe these drugs for either the treatment of type 2 diabetes or obesity.

Taking GLP-1s 

These drugs, which mimic the body's GLP-1 hormone, are usually injected into the fatty layer of tissue under the skin. Modifications have been made to some of these drugs to make them last longer in the body and have prolonged effects, so that they do not need to be injected as frequently. This can make taking the drug easier to stay on top of.⁷ 

Why the recent increase in popularity?

We have seen a big increase in recent years in the use of these drugs to help people lose weight, as for many people, weight loss is often a very difficult and long road. It is important to recognise that there is no one-size-fits-all approach to weight loss. People gain excess weight and struggle to break bad lifestyle habits for many different reasons. Pharmacological approaches can be useful in aiding individuals who struggle with losing weight and help them to maintain weight loss long-term.⁵ 

It is important to recognise that GLP-1s are not quick-fix solutions for obesity, and lifestyle counselling should also be implemented. Some people will struggle more with managing weight loss; therefore, it is essential to encourage healthier lifestyle changes and not leave people to rely on GLP-1s. 

People who are genetically predisposed to weight gain, or who suffer from stress and emotional trauma, can find it harder to maintain a healthy weight. Lifestyle counselling alone may not always have a significant enough effect to help everyone, so GLP-1s are a valuable tool that, when used alongside lifestyle changes, can help to aid in an individual's weight loss journey. 

GLP-1s and type II diabetes 

The primary method for the treatment of type 2 diabetes is a drug called metformin. It is the first line of treatment for managing diabetes, due to its having been around for a very long time and being a safe, reliable, and cheap option for treatment.⁸

GLP-1s were developed for treating type 2 diabetes. Metformin does not work for everyone, and some people may not react well to this drug. So GLP-1s are still a vital medicine available for those who have type 2 diabetes. The increased use of this drug highlighted its powerful effects on weight loss in individuals.

Why are GLP-1s used for weight loss?

After seeing the effects of GLP-1 drugs on weight loss, clinical trials have been carried out to determine which ones are safest and effective. Liraglutide and semaglutide are two of the main GLP-1 agonist medications that you may have read about. Out of the two, semaglutide has been shown to have a greater impact on weight loss. It also has a longer half-life; essentially, this means the drug remains in the body for a longer period. So its effects last for longer, and therefore it needs to be taken less. Semaglutide medications, such as Wegovy, only need to be injected once a week.⁹

You may have heard of Ozempic. It has gained online popularity in recent years. Ozempic is a semaglutide that is prescribed only for the treatment of type 2 diabetes. Wegovy, on the other hand, is a semaglutide that is prescribed for the treatment of obesity. It is given as a higher dose, which increases its effects of increased appetite suppression and therefore weight loss.¹⁰ 

Side effects 

So it’s known that semaglutide medications have the biggest effect on weight loss out of all the GLP-1 agonist medications. It is important to recognise the risks and side effects that come with taking these drugs. The most common side effects observed are gastrointestinal issues, such as nausea, vomiting, diarrhoea, constipation, bloating, and heartburn.¹¹

Nutritional deficiencies are also a concern due to decreased appetite and intake of calories, which can also lead to muscle and bone density loss. This highlights the importance of not solely relying on pharmacological intervention for weight loss. It should be used in conjunction with physical activity, which will help to preserve muscle mass and keep your body more active and able. While someone taking GLP-1s will naturally want to eat less, which can lead to an inadequate intake of essential nutrients and vitamins over time, it is still important to fuel the body with nutritional foods and be on top of what you are eating.¹²

GLP-1s are a catalyst and not a cure 

Obesity affects the body far deeper than we can see. Significant weight loss can trigger hormonal changes in the body. For example, leptin is another hormone which is involved in appetite and can signal a feeling of fullness to the brain. After significant weight loss, lower levels of leptin are found in the blood, increasing appetite and making weight loss harder to maintain.

Other hormones involved in controlling food intake include: 

• Ghrelin
• Cholecystokinin 
• Peptide YY
• Pancreatic polypeptide

This highlights the complexity of obesity, and while GLP-1s can help to kickstart weight loss and be a starting point for many people. But they are not a magic fix for weight gain, and often when stopping the drug, weight regain is observed.¹³

As the body's natural hunger signals return when stopping the drug, it leads to increased appetite and hunger, which can make it very difficult to maintain weight loss. Glp-1s can be used long-term to help maintain a healthy weight. It is important to come off the drug under medical supervision.¹⁵ 

Long-term health implications of GLP-1s use

Glp-1s are relatively new to the market, and while they are considered safe and effective, the long-term health implications that may come from the extended use of this drug are not known. For this reason, many people may not want to stay on these drugs for a prolonged period. 

Summary 

Glp-1s are valuable as they can help people to begin their journey towards better, long-lasting health. They can offer the motivation and physical change that people need when weight loss can sometimes feel impossible. I hope this article has highlighted the benefits of using GLP-1s in aiding people's weight loss journey, but also emphasised that long-lasting health requires more than just a prescribed drug; it needs support, structure, and self-compassion. With the correct tools and plans in place, GLP-1s can help alter the way we look at weight loss in years to come.