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Food guides to help consumers make healthy choices have recently been released in three countries: Japan, Canada, and the United States. The visual symbol that introduces key concepts is a spinning top in Japan, a rainbow in Canada, and a pyramid in the United States. The main features of the new guides are given in printed consumer resources, and more detailed information is available at related websites. Although the process of developing the guides varied among the countries, the resulting recommended food patterns are remarkably consistent.

Background Cognitive dietary restraint (perceived ongoing effort to limit dietary intake to manage body weight) is common in women at all life stages. In young women, high dietary restraint has been associated with both increased excretion of cortisol (a stress hormone) and reduced bone mass. Whether this occurs in older women is unknown and is reported here for the first time. Methods Postmenopausal women (49-75 years old) with high (n = 41) or low (n = 37) dietary restraint were compared to examine differences in urinary cortisol excretion, body composition assessed by dual-energy x-ray absorptiometry (bone mineral density, % body fat), dietary intake, anthropometrics, current exercise, and perceived stress. Results Women with high or low dietary restraint did not differ in age, body mass index, waist-to-hip ratio, energy intake, perceived stress, current exercise, or measures of body composition. However, urinary cortisol excretion was higher in the high restraint group (248.2 +/- 61.7 nmol/d vs 204.3 +/- 66.1 nmol/d; p =.01). Multiple regression analysis indicated that restraint group (high or low) independently predicted 7.6% of the variance in cortisol excretion. Conclusions Postmenopausal women with high dietary restraint excrete more cortisol than do those with low restraint, suggesting that dietary restraint may be a source of stress. Although this was not associated with negative health effects in this sample, further investigation is warranted.

A recent report describes a new paradigm for planning the dietary intakes of groups, the goals of which are to achieve low prevalences of both inadequate and excessive intakes. However, there are many challenges involved in properly implementing these methods, and pilot studies are urgently needed. For individuals, the target for nutrient intakes is usually the Recommended Dietary Allowance (RDA); for nutrients without an RDA, the Adequate Intake (AI) can be used. Intakes should be planned so they do not exceed the Tolerable Upper Intake Level (UL). Several applications illustrating how to use the DRIs for planning the diets of individuals have been published, so this review will focus primarily on the methods that are recommended for planning the diets of groups.

Dietary Reference Intakes (DRIs) are now available for energy, macronutrients, fiber, vitamins, and minerals, and can be used to plan diets for individuals. This article defines the four DRIs (the Estimated Average Requirement, the Recommended Dietary Allowance, the Adequate Intake, and the Tolerable Upper Intake Level), and describes two other reference standards--the Estimated Energy Requirement and the Acceptable Macronutrient Distribution Range. Planning diets for individuals involves identifying the appropriate nutrient intake goals, translating the nutrient goals into food intake (and supplement use, if warranted), assessing the plan, and revising it if required. This process is illustrated using case studies of a female vegetarian marathon runner and an older male smoker.