GLP-1 vs Aspirin for Colorectal Cancer: A Bahamian Researcher's Study

A Bahamian-led study on GLP-1 drugs and colorectal cancer

In January 2026 The Tribune reported that Dr Colton Jones, a Bahamian cancer fellow at the University of Texas Health Science Center at San Antonio's Mays Cancer Center, led an international real-world study suggesting that diabetes and obesity drugs may help prevent colorectal cancer¹. The work was presented at the American Society of Clinical Oncology Gastrointestinal Cancers Symposium in San Francisco (abstract 18)¹³. "As a Bahamian spearheading research of this magnitude, I believe this is a proud moment for our nation," Dr Jones told the paper¹.

Study design and results

The team used TriNetX, a de-identified database of health records from 106 health organisations⁵, and matched GLP-1 receptor agonist users with aspirin users by propensity score: 281,656 patients, 140,828 in each arm, mean age 58, about 69 % women²³. Follow-up began six months after the first prescription; median follow-up was 2,153 days for GLP-1 users and 1,743 days for aspirin users².

• Main result. Colorectal cancer risk was 35.7 % lower with GLP-1 drugs than with aspirin (hazard ratio 0.643; 95 % CI 0.531–0.778)⁵.
• High-risk patients. In people with a family history, genetic predisposition or specific comorbidities, the reduction was 42.1 % (HR 0.579; 95 % CI 0.401–0.837)⁵.
• Absolute numbers. Incidence was 0.13 % with GLP-1 drugs and 0.176 % with aspirin³; more than 2,000 people would need to be treated for one person to have a lower risk².
• Subgroups. Protection appeared strongest in people who started before age 45 and was seen regardless of obesity or diabetes status; no reduction was seen in tobacco users or people with atherosclerotic disease¹.
• Safety. Acute kidney injury, stomach ulcers and gastrointestinal bleeding were less common with GLP-1 drugs; diarrhoea and abdominal pain were more common².

Reports differ on which individual drugs reached significance: The ASCO Post listed semaglutide, liraglutide and dulaglutide², while AJMC reported semaglutide (risk ratio 0.758) as the only agent with a significant benefit and noted small samples for the others³. Both agree tirzepatide did not show a significant effect²³.

Why aspirin was the comparator

"While aspirin has been studied for colorectal cancer prevention, its modest benefit and bleeding risks limit its use," Dr Jones said². In 2022 the US Preventive Services Task Force concluded that "the evidence is unclear whether aspirin use reduces the risk of colorectal cancer incidence or mortality"⁶. An earlier analysis in drug-naive patients with type 2 diabetes compared GLP-1 drugs with seven other antidiabetic classes and also linked them to lower colorectal cancer risk⁸.

Limits of the evidence

This is a retrospective analysis of database records⁵, presented at a meeting¹, not a randomised trial; propensity matching balances only the factors that were measured, so unmeasured differences between people prescribed GLP-1 drugs and people taking aspirin can remain. The cohort was predominantly white and female, and Dr Jones said "Because Black men have higher CRC incidence and mortality, further studies are needed to validate these findings"³. The Tribune noted that clinical trials will be needed¹. The American Cancer Society states plainly that GLP-1 drugs "are not approved for cancer prevention" and that some early findings hint at a possible association with thyroid cancer that needs more research⁴.

What it means in The Bahamas

The finding matters locally because of who could be treated. The Tribune cited a 2025 PAHO study placing The Bahamas first in the Americas for adult obesity, with about 40 % of adults diagnosed with obesity; GLP-1 drugs cost $250 to more than $1,500 a month and are not covered by the national prescription drug plan, though the Wellness Minister has said NHI coverage is planned⁷. The cardiometabolic case is already established: in SELECT, semaglutide cut major cardiovascular events by 20 % in people with obesity and cardiovascular disease⁹, and in STEP 1 it produced a mean 14.9 % weight loss at 68 weeks¹⁰. The World Health Organization's December 2025 guideline conditionally recommends GLP-1 drugs for adults with obesity¹¹. A cancer signal, if confirmed in trials, would add to that case; it does not yet justify prescribing for prevention⁴.