A study recently published in the American Journal of Clinical Nutrition has found that older women who use multivitamins might be more likely to develop breast cancer than those who do not use the supplements. Or it might just be a statistical anomaly. Or people may use multivitamins because of other unhealthful behaviors - such as lack of a good diet.
Over 35,000 Swedish women, ages 49 to 83, were interviewed over a 10-year time span. All of the women were cancer-free at the beginning of the study, but 974 of them had developed the disease within the decade.
Those who used multivitamins were 19-percent more likely than non-users to develop cancer, though only 293 of over 9,000 vitamin users developed the ailment. In comparison, 681 of the more than 26,000 women who did not use vitamins were ultimately diagnosed with breast cancer.