Vitamin D may help in reducing the risk of osteoporosis, a new study suggests. Scientists Niigata University of Medicine in Japan observed 136 women over age 40 (average age 65) in rural Japan in February 1999. Despite staying inside all winter, the mean serum vitamin D level of these women, 60 nmol/L, was one of the highest ever reported. Only 5 to 8 per cent of the women were deficient in the vitamin. Researchers assessed diets via food frequency recall, and discovered that high fish and egg consumption could be linked to high vitamin D levels. Scientists concluded that the higher vitamin D levels found in the Japanese women may protect them from osteoporosis despite their lower calcium intake. Results of the study are published in the May 2000 issue of American Journal of Clinical Nutrition.