Dietary supplementation is being increasingly applied by athletes to maintain physical condition and improve performance. This brief review summarizes the classification and role of nutritional ergogenics in the requirements for energy, protein/amino acids, vitamins and minerals in sports. Guidelines are shown for the theory, effectiveness, safety, legal and ethical aspects to evaluate the claims made for ergogenic aids. Recommendations for using dietary supplements during a program of weight reduction, during vigorous training, and before and during exercise are described. The aspects of nutritional education and dietary support for the suitable use of supplements by young and adult athletes, and the role of sports dietitians are briefly described.

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Dietary surveys of a population-based study have been beneficial to the National Nutrition Survey (NNS). Since 1995, the approximated proportion method (Method A) has been used in Japan for nutritional surveys conducted for the NNS. However, the estimated validity of the method has not been given sufficient consideration. Thirty-two students studying at a training facility for dietitians and 32 of their family members who were in charge of cooking were studied to identify the validity of Method A and the cause of the error observed between Method A and the individual-based food weighing method (Method B).
Energy and macronutrient intake by individual subjects obtained through Method A showed a high correlation with those obtained through Method B (r=0.89-0.91). However, compared to Method B, Method A tended to systematically underestimate the mean value for energy intake by 94kcal/day. Method A causes excessive errors because it involves a large number of families and mixed dishes. A comparison of the two methods regarding energy intake from boiled rice indicated that values obtained through Method A are systematically low compared those obtained through Method B. Special attention should be given to the error for energy intake from boiled rice as it alone accounts for 50% of the underestimation.

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A generation comparison of body shape consciousness was made with 458 pairs of women university students and their mothers as subjects.
The mean BMI was 20.2±2.0 for the students and 22.2±2.5 for the mothers. The current body shape was slender for 17% of the students and for 4% of the mothers, and obese for 2% of the students and for 14% of the mothers. Those dissatisfied with their present body shape were 84% of the students and 75% of the mothers, the generation difference being significant. However, the percentage of those who evaluated their present body shape as overweight was approximately 62% for both the students and mothers.
A generation comparison of the proportion who responded “affirmative” to the body shape questionnaire (BSQ) items related to the body shape indicated that the proportion of those currently slender who responded that “they wish to remove the fatty portion of the body” was 66.2% for the students and 15% for the mothers, suggesting an almost abnormal desire of the students to be slender. Furthermore, the BSQ score was higher for the students, although both generations gave a body shape classification that also showed body shape consciousness>food con-sciousness>obesity stress consciousness.
According to the results of a factor analysis of the consciousness to BSQ items, the first factor was interpreted as “conscious frustration about an obese body shape (a wish to be slender)”, while the second factor was “consciousness of an inferiority complex toward an obese body shape when compared to others”, and the third factor was “food consciousness”. A significant generation difference was apparent in the first factor and second factor, the proportion being high in the students, but no generation difference was apparent in the third factor.
These results indicate that the ideal BMI of students is a slender body shape, and that an ideal body shape consciousness exists in those desiring to be slender. Those desiring to be slender and the results of BSQ demonstrate the level of inherent consciousness of being slender and the concern of an inferiority complex directed toward the body shape.

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The Ca content of traditional tofu was clearly rich, because CaSO₄ is used as a coagulant. However, the Ca content of contemporary tofu was found to be poor due to Mg salt or saccharic acid being used as the coagulant. In order to learn more about this variation, the Ca and Mg contents were measured for Momen tofu (regular tofu, n=22), Kinugoshi tofu (tofu with whey, n=13) and pre-packed tofu (n=12) sold in four areas of Nagasaki prefecture. These measured contents were compared with those in the Standard Tables of Food Composition in Japan (5th revised edition). The contents of Ca and Mg greatly varied with the same type of product from different manufacturers and among the three different types of tofu. The Ca content was negatively correlated with the Mg content in all tofu samples (p<0.01). This result is due to the fact that Momen tofu, in which CaSO₄ was used, did not use Mg salt as the coagulant, while pre-packed tofu, in which Mg salt was used, did not use CaSO₄ as the coagulant. 60% of the Momen tofu samples had a Ca content lower than that in the standard tables, and the figure for one-third of all Momen tofu samples was less than 30% of that in the standard tables. In contrast, the Mg content of all Momen tofu samples was higher than that in the standard tables. The Ca and Mg contents of all Kinugoshi tofu and pre-packed tofu samples were more than those in the standard tables. These results indicate that it is important to read the labels and to choose the kind of tofu when it is to be used in a menu as the Ca source.

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