Weight-loss drugs could reduce the risk of cancer developing in obese people

The use of GLP-1 agonists is associated with a reduced overall risk of cancer. This is the conclusion of a study published Wednesday in the scientific journal Jama Oncology. The study, conducted with data from more than 86,000 overweight or obese adults over a 10-year period, compared the medical histories of patients who had been taking these anti-obesity drugs (known by their brand names Ozempic or Wegovy) with patients who had not undergone treatment. The incidence rates for the 14 types of cancer studied were 13.6 versus 16.4, respectively, indicating a significantly lower overall risk of cancer among people taking GLP-1. This was especially evident in endometrial, ovarian, and meningiomas.

The study is important, if somewhat expected. It demonstrates with statistical data something that could be inferred from a simple cause-and-effect analysis. GLP-1 agonists lead to weight loss of up to 20% in 72 weeks. Furthermore, obesity is a risk factor for at least 13 types of cancer (the present study analyzed all of these, plus lung cancer). A study led by Barcelona’s Hospital del Mar concluded that obesity increases the risk of cancer by 12 in women and doubles the risk in men. The potential effect of Ozempic and other similar drugs is therefore not surprising. It reduces obesity and, with it, the risk of certain types of cancer.

However, it’s not all good news. The use of these drugs may be associated with an increased risk of kidney cancer, the study states, although it describes it as “insignificant.” “This highlights the need for longer-term follow-up to clarify the underlying mechanisms and clinical implications of these findings,” explain the authors, from Indiana University. Another surprise was a reduction in lung cancer rates. It wasn’t significant (1.6 per 1,000 people among users versus 2.03 for non-users), but it could point to the role these drugs can play in managing addiction, as many users have stopped not only eating excessively while using them, but also smoking.

The study is significant for the quantity and quality of its data. All patients studied were eligible for treatment with GLP-1 agonists, so they had similar rates of obesity. They had no history of cancer, their average age was 52, and 68% were women. The authors welcome the data obtained in this epidemiological study, but caution that further medical research is needed into the relationship between cancer and these drugs.

Scientists continue to discover new ways in which GLP-1 receptors work. Originally designed to regulate insulin production, they later emerged as potent appetite suppressants. Various studies have also suggested they play a crucial role in controlling addiction. A recent trial showed they prevent fat accumulation and liver fibrosis. They also reduce inflammation, which could explain the results of this new study. Inflammation could be a determining factor in obesity-related cancers.

Obesity now affects more than one billion people, according to figures from the World Health Organization. A study published last year in The Lancet revealed that excess weight is the most common form of malnutrition in most countries: cases in children have quadrupled in three decades, and in adults, they have almost tripled.

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