Evolution of dietary guidelines.

Advice on eating behavior, food choices, and food preparation have been incorporated into philosophical and religious writings over the ages; however, in the past 150 years, these recommendations have been based on science related to public health policy and medicine. In the first half of the 20th century, the focus was on sanitation and prevention of nutrient deficiency diseases. In the second half, the focus has shifted to prevention of chronic disease and dietary excesses that increase disease risk. Current guidelines recognize the importance of lifestyle as well as food and nutrition choices. Dietary guidelines that were developed in the early 1980s emphasized components of food such as saturated fat, individual nutrients, or fiber. Revisions of these guidelines have placed more emphasis on food choices rather than individual nutrients, and recommendations have become more food-based. The process developed by the Food and Agricultural Organization and World Health Organization for preparation and use of food-based dietary guidelines begins with analysis of the most critical public health issues that are related to diet and outlines strategies to identify food-based approaches to address these issues. Countries that have implemented this process indicate that consensus building accomplished through the process has allowed a multisector approaches for addressing diet-related public health problems.