Fish as a major source of vitamin D in the Japanese diet

OBJECTIVES: We investigated the amount and sources of vitamin D in the Japanese diet by analyzing diet records collected over a 4-mo period. METHODS: Dietary data for this study were provided by a nursing home in Niigata, Japan. Diet records, written by the nursing home’s dietitian, for 122 consecutive days between September and December 1999, were used. The amount of food for an individual was weighed before cooking and recorded on the diet record. Vitamin D–containing foods, including fish, eggs, meat, and mushrooms, were selected from the diet records, and their vitamin D (vitamin D2 plus D3) per day was calculated by referring to the Standard Tables of Food Composition in Japan. RESULTS: The overall average vitamin D intake per day was 7.10 μg (284 IU), which is about 70% of the recommended dietary allowance of 10 μg (400 IU). There were no significant differences in vitamin D values over the 4 mo (P = 0.822). Overall, the contribution of vitamin D from fish to total vitamin D intake was 90.7%, followed by mushrooms (4.4%), eggs (3.2%), and meat (1.7%). CONCLUSIONS: Frequent fish intake appears to be an advisable health practice in terms of preventing vitamin D insufficiency in the elderly.