Weight loss drugs slash cancer risk – new study suggests major benefit

Tanya Reynard | Last update: 16th May 2025

TL;DR:

• New Israeli study of over 6,300 patients shows GLP-1 drugs reduce cancer risk as effectively as bariatric surgery — and may work better when adjusted for weight loss
• Study published in The Lancet eClinicalMedicine and presented at the European Congress on Obesity (ECO 2025) in Málaga, Spain
• Researchers tracked patients for an average of 7.5 years
• GLP-1 weight loss drugs were linked to a 41% greater protective effect against obesity-related cancers than surgery
• Adds to growing evidence that these drugs may also reduce addiction, heart disease, and inflammation

The study: from Israel, and the largest of its kind

This groundbreaking research was led by Prof. Dror Dicker of Hasharon Hospital at Rabin Medical Center in Petah Tikva, Israel, and co-authors from Clalit Health Services. The results were published in The Lancet eClinicalMedicine and unveiled at ECO 2025, one of the world’s top obesity research conferences.

Participants: 6,300+ Israeli adults with obesity and type 2 diabetes
Study Period: Patients followed for 7.5 years on average (some up to 12.9 years)
Interventions Compared:

• GLP-1 drugs: liraglutide (Saxenda), dulaglutide (Trulicity), and exenatide (Byetta)
• Bariatric surgery: sleeve gastrectomy and gastric bypass

Despite surgery patients losing nearly twice as much weight, the cancer risk reduction was almost identical:

• Bariatric surgery group: 150 cancer cases among 3,178 patients
• GLP-1 drug group: 148 cancer cases among 3,178 patients

But here’s the twist: after adjusting for the greater weight loss seen with surgery, GLP-1 drugs showed a 41% stronger protective effect against obesity-related cancers.

🔗 Read the full study in The Lancet eClinicalMedicine

How are weight loss drugs fighting cancer?

It’s not just the weight loss. GLP-1 weight loss drugs mimic a natural gut hormone that regulates hunger and insulin. This hormone also appears to reduce systemic inflammation, a known driver of cancer. According to Prof. Dicker, this is likely a key reason for the anti-cancer effects seen in the drug group.

The study tracked cancers with known obesity links: breast, colorectal, uterine, ovarian, pancreatic and liver cancers. For patients on weight loss drugs, risk across these categories dropped significantly.

And unlike surgery, which carries more upfront risk and can be invasive, GLP-1s offer a non-surgical route to meaningful cancer prevention.

What else could these drugs do?

This isn’t the first time GLP-1 medications have surprised researchers. Other studies are now exploring whether these drugs might also reduce cravings for alcohol, cigarettes and opioids, by dampening reward responses in the brain.

Combined with earlier findings on heart protection, improved fertility, and reduced blood pressure, the GLP-1 weight loss drugs are emerging as some of the most versatile and powerful tools in preventive medicine.

And with new formulations like once-weekly injections or even daily pills in development, access and adherence could soon become easier than ever.

Why this matters now

Obesity remains one of the biggest drivers of cancer worldwide, yet options for safe, long-term risk reduction have been limited. This study from Israel is the first to directly compare weight loss drugs to surgery over nearly a decade, and the results are hard to ignore.

Whether you’re already using a weight loss drug or still deciding, this isn’t just about aesthetics. It’s about lowering your long-term disease risk – and maybe even outpacing what surgery can achieve. Good news for the SlimrChat community.