Weight Loss Lowers Risk of Obesity-Related Cancer, Study Finds

Real-world weight loss may be linked to a reduced risk of obesity-related cancers, according to new late-breaking data presented at the American Diabetes Association (ADA) 84th Scientific Sessions.¹

These results demonstrated a correlation between weight loss and a decrease in the threat of obesity-related cancers at 3- and 5-year study endpoints. The risk for all other types of cancers was lowered across all time intervals measured in the study (P <.001).

“This study reinforces how crucial it is to treat obesity as a chronic disease,” said study author Kenda Alkwatli, MD, a clinical fellow at the Cleveland Clinic.²

Previous research has found 64% of adults without diabetes presented with overweight or obesity, compared with 62% of those with type 1 diabetes (T1D) and 86% of those with type 2 diabetes (T2D).³ Excess body weight has been linked to an elevated risk of >13 types of cancer due to excess estrogen and raised insulin levels, including breast, kidney, ovary, liver, and pancreatic cancers.⁴

As a result, Alkwatli and colleagues stressed the need for further research into the correlation between diabetes, obesity, and cancer, and the corresponding treatments.¹ A total of 172 patients, including 100,143 in the control arm and 5,329 cases, were identified from the electronic health record at Cleveland Clinic.

The Centers for Disease Control and Prevention (CDC) defines overweight as a body mass index (BMI) above 25, while a BMI over 30 is considered obese.⁵ The median BMI was 34.2 for cases and 34.5 for controls, with each exhibiting obesity.¹

In the retrospective, observational study, the association between the percentage change in BMI at 3-, 5, and 10-year intervals before cancer diagnosis versus control for each cancer endpoint was measured using the logistic regression models.

The analysis’ primary endpoint was the 13 identified obesity-related cancers. Secondary endpoints involved the occurrence of 16 other cancer types, including melanoma and skin malignancies and cancers related to the urinary tract, hematopoietic and lymphoid tissues, respiratory and intrathoracic organs, male genital organs, female genital organs, eye, brain and other parts of the central nervous system, and digestive organs.

Upon analysis, Alkwatli and colleagues found real-world weight loss was associated with a reduced risk of obesity-related cancers. These data revealed weight loss was linked to a reduction in the risk of obesity-related cancers at 3 years (odds ratio [OR], 0.99; 95% CI, 0.984 - 0.996) and 5 years (OR, 0.989; 95% CI, 0.983 - 0.995).

Weight loss also correlated with a reduced risk of all types of cancers across all time points (ORs <1; P <.001). In particular, the risk was reduced for renal cell carcinoma (3 years), multiple myeloma (10 years), and endometrial cancer (3 and 5 years) among primary cancer endpoints (P <.05).

Investigators indicated more research is necessary to evaluate if cancer risk is affected by the amount, rate, and weight loss method. Thus, future studies may focus on the effect of specific anti-obesity medications on reducing cancer risk.

“We are hopeful that these results can help us better understand how we can use weight loss to address comorbidities including cancer in patients with obesity,” Alkwatli added.

References

1. _{Preiss D. Reduced Risk of Obesity-Related Cancers with Real-World Weight Loss. Late-breaking poster presented at the American Diabetes Association (ADA) 84th Scientific Sessions. Orlando, Florida. June 21-24.}
2. _{American Diabetes Association. Weight Loss is Associated with Decreased Cancer Risk in Individuals with Obesity. Published June 21, 2024. Accessed June 21, 2024.}
3. _{Fang M, Echouffo-Tcheugui JB, Selvin E. Prevalence and Management of Obesity in U.S. Adults With Type 1 Diabetes. Ann Intern Med. 2023;176(9):eL230228. doi:10.7326/L23-0228}
4. _{Islami F, Goding Sauer A, Gapstur SM, Jemal A. Proportion of Cancer Cases Attributable to Excess Body Weight by US State, 2011-2015. JAMA Oncol. 2019;5(3):384–392. doi:10.1001/jamaoncol.2018.5639}
5. _{About adult BMI. Centers for Disease Control and Prevention. June 3, 2022. Accessed June 21, 2024. https://www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/index.html}