Vitamin D: What role in obesity-related cancer?

Obesity is an important risk factor for incidence and death for many types of cancer. Vitamin D reduces risk of incidence and death for many types of cancer. This review outlines the mechanisms by which obesity increases risk of cancer, how vitamin D reduces risk of cancer, and the extent to which vitamin D counters the effects of obesity in cancer. Vitamin D is a partial ally against some of obesity's pro-carcinogenic effects, notably by reducing inflammation and regulating sex hormone receptors, leptin resistance, cellular energy metabolism, the microbiome, and hypoxia. However, it can act stronger in against the renin-angiotensin system, insulin resistance, and oxidative stress in cancer. Additionally, excess fat tissue sequesters vitamin D and, along with its dilution in increased body volume, further reduces its bioavailability and serum concentration, limiting its protective effects against cancer. In conclusion, while vitamin D cannot reverse obesity, it plays a significant role in mitigating its pro-carcinogenic effects by targeting several mechanisms. © 2025