Vitamin D Boosts Breast Cancer Chemotherapy Success by 79%: What the New Study Means for You

# Vitamin D Boosts Breast Cancer Chemotherapy Success by 79%: What the New Study Means for You

> **Quick answer:** A randomized clinical trial published April 28, 2026, found that women taking a low-dose vitamin D supplement during breast cancer chemotherapy were nearly twice as likely to achieve complete cancer remission — 43% versus 24% in the placebo group. Researchers call for larger studies, but say the finding deserves urgent attention given how safe and affordable the supplement is.

A $10 bottle of vitamin D from your pharmacy shelf could nearly double your chances of achieving complete cancer remission. That is the implication of a newly published randomized trial, and it is generating genuine excitement in the oncology community — because few interventions this affordable have ever shown results this large.

The study from Brazil's Botucatu School of Medicine at São Paulo State University (FMB-UNESP) found that women taking 2,000 IU of vitamin D daily during neoadjuvant chemotherapy were 79% more likely to see their breast cancer completely disappear before surgery than those on a placebo. If confirmed in larger trials, this could reshape standard-of-care protocols for breast cancer patients worldwide.

## The Study: What Happened and What Was Found

The research, published in the journal *Nutrition and Cancer* and highlighted by ScienceDaily on April 28, 2026, was a six-month prospective randomized clinical trial involving 80 women over age 45 who were preparing to undergo neoadjuvant chemotherapy — treatment given before surgery to shrink tumors and make removal easier.