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Lynda

By Maria Fernanda Ziegler

Snip

In a study conducted at São Paulo State University involving 80 women over the age of 45, low-dose vitamin D supplementation nearly doubled the rate of treatment response.

A study conducted at the Botucatu School of Medicine at São Paulo State University (FMB-UNESP) in Brazil found that low-dose vitamin D supplementation can improve the effectiveness of chemotherapy in women with breast cancer. The findings suggest that vitamin D may serve as an alternative to other drugs designed to boost chemotherapy response, especially those that are difficult to access.

The research, supported by FAPESP, included 80 women over the age of 45 who were preparing to begin treatment at the oncology outpatient clinic of the general and teaching hospital (“Hospital das Clínicas”) at FMB-UNESP. The women were divided into two groups: one group of 40 received 2,000 IU (international units) of vitamin D daily, while the other 40 received placebo tablets.

After six months of cancer treatment and supplementation, 43% of the women taking vitamin D saw their tumors disappear following chemotherapy, compared to 24% in the placebo group. All participants underwent neoadjuvant chemotherapy, a treatment used to shrink tumors before surgery.

“Even with a small sample of participants, it was possible to observe a significant difference in the response to chemotherapy. In addition, the dosage used in the research [2,000 IU per day] is far below the target dose for correcting vitamin D deficiency, which is usually 50,000 IU per week,” says Eduardo Carvalho-Pessoa, president of the São Paulo Regional Brazilian Society of Mastology and one of the authors of the article published in the journal Nutrition and Cancer.
Immunity

Vitamin D is a hormone that helps the body absorb calcium and phosphorus, both of which are essential for maintaining healthy bones. Recent research has also shown that vitamin D supports the immune system and helps fight infections and diseases, including cancer. However, most studies that have explored the connection between vitamin D and cancer have used high doses of the supplement.

This hormone is obtained primarily through exposure to sunlight and food. The recommended daily intake is 600 IU for those who are not deficient in the vitamin, and 800 IU a day for older people. The American Academy of Pediatrics recommends 400 IU of vitamin D per day for babies.

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https://www.tandfonline.com/doi/full/10.1080/01635581.2025.2480854