Vitamin D and Breast Cancer Risk: Evaluating the Association and Effective Risk Reduction

Breast cancer (BC) is the most common cancer among women globally. Vitamin D has been considered a protective factor; however, its relationship with any aspect of the disease remains controversial.

A cross-sectional, single-center clinical study was conducted between 2015 and 2018, including 141 women diagnosed with BC and 239 women in the control group, with mean ages of 43.1 and 41.7 years, respectively (p = 0.103). Serum levels of vitamin D and lipid profile were measured. Clinical and nutritional data were obtained through interviews and medical records.

The vitamin D dosage presented an average value of 25.5 ng/mL and 31.0 ng/mL in the case and control groups, respectively (p < 0.001). The vitamin D cut-off point for discriminating the presence of BC was 27.45 ng/mL. Additionally, low-density lipoprotein cholesterol levels were higher in the case group (121.4 mg/dL) compared to the control group (110.7 mg/dL) (p = 0.002), whereas high-density lipoprotein cholesterol levels were lower in the case group (47.6 mg/dL) compared to the control group (53.3 mg/dL) (p = 0.001). Alcohol consumption was significantly higher in the case group than in the control group (2.7 vs. 5.3 doses/day; p < 0.001).

The results indicate a significant association between lower vitamin D levels and BC, persisting after multivariate analysis (p < 0.001). These findings could inform prevention strategies, highlighting the importance of maintaining adequate vitamin D levels and potentially identifying a risk group.