A study from Brazil has found that a small daily dose of vitamin D can help breast cancer treatment work better.
The study was done at the Botucatu School of Medicine at São Paulo State University.
It showed that women who took 2,000 IU (international units) of vitamin D daily while getting chemotherapy responded better to the treatment than those who took a placebo.
The research included 80 women over age 45 who were starting chemotherapy for breast cancer. Half of them took vitamin D, and the other half took placebo pills. After six months, 43% of the women who took vitamin D had their cancer disappear, compared to just 24% of those in the placebo group.
All the women in the study were receiving what is called neoadjuvant chemotherapy. This type of chemotherapy is given before surgery to help shrink the tumor and make surgery easier.
Vitamin D helps the body absorb calcium and phosphorus, keeping bones healthy. It also plays an important role in the immune system. Some studies suggest it may help fight diseases, including cancer. But most past studies used very high doses of vitamin D, unlike this one, which used a much lower dose.
People usually get vitamin D from sunlight and food. The daily recommended amount is 600 IU for adults, or 800 IU for older people. Taking too much vitamin D can be harmful and cause problems like vomiting, weakness, and kidney stones.
In this study, most of the women had low vitamin D levels—below 20 nanograms per milliliter of blood. After taking supplements, their vitamin D levels increased during treatment, which may have helped them recover.
Vitamin D is cheaper and easier to get than many drugs used to improve chemotherapy results. Some of those drugs aren’t even available in Brazil’s public health system.
The researchers say more studies with larger groups of women are needed. But they believe these early results show vitamin D may help improve chemotherapy success and increase the chances of breast cancer remission.
The study is published in Nutrition and Cancer.
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