In recent years, improvement of the food supply, changing eating habits, and so on cause the increase in obesity in Japan. On the other hand, average BMI of young women is around 20, which is judged as thin. Our groups are periodically carrying out a survey about their eating habits from 1972, especially niacin sources and intakes. In this paper, we report the result being carried out in 1998. Subjects are36 female college students (21-22 years old, 158 cm, 52 kg, 20.7 BMI). The subjects consumed self-selected foods for one day and a sample blood was taken from an arm vein at the next morning and the sample blood was used for measuring NAD and NADP. Energy intake was below the Recommended Daily Allowance (RDA) 1800 kcal, nevertheless, "niacin equivalent (NE) intake/ 1000 kcal" was 16.1 mg, which is three-times higher compared with the RDA, 6.3 mg/1000 kcal. However, energy intake dropped from 2155 kcal in 1972 to 1448 kcal/day in 1998, and NE intake also dropped from 31.3 mg/day in 1972 to 23.4 mg/day in 1998. A significant relationship between energy and NE intakes was observed. A main source of supply of NE was fish and meat low in fat. These were similar results obtained during recent 30 years. This is because Japanese eating habit that like low-fat and high-protein foods such as fish and low-fat-meats, do not fundamentally change. The blood NAD and NADP levels (nmol/ml of whole blood) were 26.6 and 12.5, respectively.