Scientists in Brazil gave a small amount of vitamin D to women with breast cancer. They wanted to see if the vitamin could make chemotherapy work better.
Eight‑zero women, all older than 45, joined the study. Half of them took a pill with 2,000 IU of vitamin D every day. The other half took a fake pill that looked the same.
All the participants received chemotherapy before surgery. After six months, the results were clear.
More cancer disappearance
In the vitamin‑D group, 43 % of the women had no signs of cancer left. In the placebo group, only 24 % reached the same result.
Why vitamin D matters
We usually think of vitamin D as the nutrient that helps our bones stay strong. New research also shows it helps the immune system fight illnesses, including cancer.
People get vitamin D from sunlight and from some foods. Official advice says most adults need 600 IU a day, and older adults need about 800 IU.
Low levels at the start
When the study began, most women had low vitamin D in their blood—less than 20 ng/mL. Doctors recommend a level of 40‑70 ng/mL for good health.
During chemotherapy, the women who took the supplement raised their vitamin D levels. Researchers think this may have helped their bodies heal.
What comes next
These early findings are exciting, but scientists need larger studies to be sure. Bigger trials will tell if vitamin D truly improves chemotherapy success for more patients.