Nutritional intakes in community-dwelling older Japanese adults: high intakes of energy and protein based on high consumption of fish, vegetables and fruits provide sufficient micronutrients

The purpose of this study was to obtain detailed data on the dietary intake of energy, macronutrients, and micronutrients, especially minerals and vitamins, of healthy free-living people over the age of 70 in Japan and to clarify the correlations among nutrient intakes. The survey was conducted in November 2001 for 57 persons (men: 31, women: 26) aged 74 y (born in 1927) living in Niigata City, Japan. A precise weighing method was used to record food intake for three consecutive days. Nutrient intake was calculated based on the Standard Tables of Food Composition in Japan (5th ed.). The intakes of energy and total protein were 44.8+/-7.7 kcal/kg/d and 1.80+/-0.35 g/kg/d for men and 38.1+/-7.6 kcal/ kg/d and 1.51+/-0.26 g/kg/d for women. These values are significantly higher than those proposed by the current Recommended Dietary Allowances (RDAs) and the data by the 2001 National Nutrition Survey in Japan. The energy intake ratios from protein, carbohydrate and fat for men were 16 : 58 : 22, respectively, and the residual part was alcohol. For women, the ratios were 16 : 62 : 22. The proportion of total protein intake that consisted of animal protein was 57.8% for men and 52.8% for women. For both sexes, all of the mean daily intakes of nine minerals and 12 vitamins were higher than those prescribed for elderly Japanese people (> or =70 y) in the RDAs. Significant strong correlations were found between total protein intake and intakes of vitamins D, B2 and B6, as well as niacin and pantothenic acid (p<0.0001). Among the nine minerals, the correlations were very strong between potassium and magnesium, calcium and phosphorus, magnesium and iron, magnesium and copper, iron and copper, and zinc and copper (r's>0.700). For vitamins, strong correlations were found between vitamin A and folic acid, vitamin B2 and pantothenic acid, and folic acid and pantothenic acid. Furthermore, strong relationships were observed between potassium and folic acid, potassium and pantothenic acid, potassium and dietary fiber, phosphorus and vitamin B2, phosphorus and pantothenic acid, iron and folic acid, zinc and vitamin B12, and copper and vitamin B12. From these results, it is evident that age is not an important determinant of dietary intake among apparently healthy elderly Japanese people aged 74 y. In addition, the high intake of energy and protein in the Japanese dietary pattern, based upon high consumption of fish and/or shellfish, vegetables, and fruits, provide sufficient minerals and vitamins.