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# Prediagnosis vitamin C reduces breast cancer death risk
- URL: https://www.foodconsumer.org/vitamin_c_reduces_breast_cancer_death_risk_1029131038/
- Published: 2013-10-29T23:37:00.000Z
- Updated: 2026-09-22T16:24:03.000Z
- Description: Among 3,405 Swedish women with invasive breast cancer followed more than 10 years, those in the top quartile of pre-diagnosis vitamin C intake were 25 percent less likely to die of the disease. Vitamin C taken after diagnosis showed no link to mortality.
- Author: Food Consumer
- Tags: Vitamins, Nutrition, #vivvo-import

Tuesday Oct 29, 2013 (foodconsumer.org) -- Taking vitamin C prediagnosis may reduce risk of mortality from breast cancer, according to a new study released in British Journal of Cancer.

Holly R. Harris from The National Institute for Environmental Medicine, Karolinska Institutet in Stockholm, Sweden and colleagues conducted the study and found taking vitamin C supplements prediagnosis was associated with 25% reduced risk of breast cancer death.

Vitamin C can help prevent and treat breast cancer as some research has shown. The study was intended to examine the association between prediagnostic use of vitamin C supplements and risk of mortality from breast cancer.

For the study, 3405 women diagnosed with invasive breast cancer in the Swedish Mammography Cohort were followed more than 10 years during which 1055 died from all causes of which 416 from breast cancer.

Patients in the highest quartile of pre-diagnosis vitamin C intake were 25% less likely to diabetes from breast cancer, compared with those in the lowest quartile.

However, post diagnosis vitamin C supplementation in a dose of 100 mg per day was not associated with risk of mortality from breast cancer.

The study concluded "Our findings suggest that dietary vitamin C intake before breast cancer diagnosis may be associated with breast cancer survival."

"In addition, post-diagnosis vitamin C supplementation at the level observed in our population was not associated with survival." (David Liu)