We explore recent headlines reporting on a new study that suggests weight-loss medicines like Mounjaro and Wegovy may protect against 42 diseases – but increase the risk of 19 others.
Weight-loss injections may lower the risk of having a cardiac arrest, heart attack or stroke, but increase the risk of drug-induced pancreatitis, according to a new study.
Over the past few years, these types of drugs – known as GLP-1 agonists – have become more and more popular in the UK and around the world for weight loss.
While they were originally designed to lower blood sugar levels in people with type 2 diabetes, GLP-1 agonists also reduce your appetite, which means they can help people without diabetes lose weight too.
Some research also suggests that these medicines can reduce the risk of a range of diseases, including heart attacks and strokes.
However, there’s still a lot we do not know about how GLP-1 agonists affect different areas of the body.
To find out more, researchers behind a new study published in the journal Nature Medicine in January 2025 looked at the impact of taking GLP-1 agonists on 175 different diseases using health information from over 2.4 million veterans with type 2 diabetes across the United States.
They compared around 215,000 people with diabetes prescribed weekly injections of GLP-1 agonists to just over 1.2 million people who continued to receive their usual non-GLP-1 medicines to reduce blood sugar.
After an average of 3.68 years, people taking GLP-1 agonists had a lower risk of developing 42 different diseases than those given their usual medicines.
This included a 22 per cent lower risk of a cardiac arrest, 11 per cent lower risk of heart failure, 9 per cent lower risk of a heart attack and 7 per cent lower risk of ischaemic stroke.
As well as heart and circulatory diseases, people taking GLP-1 agonists were 24 per cent less likely to have liver failure, 22 per cent less likely to have respiratory failure and 12 per cent less likely to develop Alzheimer’s disease.
GLP-1 agonists were also linked to a lower risk of some mental health issues, such as substance use disorders, suicidal ideation and schizophrenia.
