Dietary intake of seven B vitamins based on a total diet study in Japan.

The present study estimated the dietary intake of seven B vitamins using a total diet study (TDS) in Japan. The daily intake of vitamins estimated by TDS was calculated based on the mean contents of vitamins in 18 food groups, and the amount of food intake in the Nation Health and Nutrition Survey in Japan, 2006. The estimated daily intake of these vitamins for all ages was 22.8 mg NE/d for niacin, 7.4 μg/d for vitamin B12, 146 μg/d for folic acid, 4.52 mg/d for pantothenic acid, 1.06 mg/d for riboflavin, and 1.44 mg/d for pyridoxine. The estimated daily intake of the vitamins of niacin, vitamin B12 and pyridoxine exceeded the dietary reference values for adults aged 18-29 y. The estimated daily intake of these vitamins by TDS was higher than the daily intake reported in the National Health and Nutrition Survey in Japan, 2006. There was a strongly positive correlation between the intake levels estimated by TDS and those reported in the National Health and Nutrition Survey. This suggests that TDS is an effective dietary survey for estimating the dietary intake of water-soluble vitamins. Therefore, when being determined by TDS, the estimated daily intake of biotin was 51.0 μg/d for all ages.