In a study of men and women with a variety of cancers, 75% of the patients had low or deficient vitamin D levels. Vitamin D helps cells develop normally and prevents the formation and spread of cancer cells.

In a study of over 4,000 women with breast cancer, those with the highest vitamin D levels had a 50% reduction in their risk of death than those with the lowest vitamin D levels. Even low dose (400 IU) vitamin D supplementation was found to reduce early stage breast cancer by 18%.

But don’t just rely on taking vitamin D-3 without knowing your level of D-3. Some people, even taking 5,000-10,000 IU’s of D-3, had a very insufficient level. Your doctor can verify your level of D-3, or contact a lab to check your level. Your level, based on many nutritional experts, should be in the range between 60 and 80 ng/mL.