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# Study confirms that Vitamin D3 may prevent cancer
- URL: https://www.foodconsumer.org/100720090619_study_confirms_that_vitamin_d3_may_prevent_cancer/
- Published: 2009-07-10T18:19:00.000Z
- Updated: 2026-09-15T12:23:49.000Z
- Description: Spanish researchers reported in the Journal of Clinical Investigation that the active form of vitamin D3 switches on CST5, the gene for the tumor suppressor protein cystatin D. They conclude CST5 may mediate the vitamin's anticancer effect and deserves study in colon cancer.
- Author: Food Consumer
- Tags: Vitamins, Nutrition, Vitamin D, #vivvo-import

By David Liu and edited by Sheilah Downey

Numerous scientific studies have suggested that vitamin D may help prevent many cancers. A new study published in the Journal of Clinical Investigation confirmed biochemically that vitamin D3 has anti-cancer effects.Alberto Muñoz and Carlos López-Otín at the Autonomous University of Madrid and the University of Oviedo, Spain, and colleagues found the active form of vitamin D3 directly activates a gene known as CST5, which is responsible for making tumor suppressor protein cystatin D. It has been shown that CST5 increases production of the protein.The authors of the study conclude that CST5 is a candidate tumor suppressor gene and it mediates the anticancer effects of the active form of vitamin D3.The results of the study suggest that vitamin D3 should be examined for its preventive and therapeutic effect against colon cancer.The active form of vitamin D3 may be made in cells when vitamin D3 reaches certain high levels in the blood, according to Dr. John Cannell, president of the Vitamin D Council, a non-profit organization.Dr. Cannell suggests that 5000 international units of vitamin D3 should be taken to maintain a healthy level of serum vitamin D when exposure to sunshine is not possible.