Principles of Biochemistry Volume 3 - A. Lehninger 1985

Selected Aspects of Human Biochemistry
Human Nutrition
A balanced diet must be multicomponent

There is no single universal food that can fully meet everyone's nutritional needs. The forty essential dietary components are found in A wide variety of foods in varying proportions. A simple and convenient guide for selecting a well-balanced diet is presented in Table 26-14, which divides all foods into four main groups. This table lists the items from each group that should be consumed daily to ensure a reasonably balanced diet. To avoid overconsuming one or a few foods from a specific group, food choices within each group should be varied from day to day. The best guarantee of proper Nutrition is a diverse diet with a specific calorie-to-protein ratio tailored to an individual's needs based on height, weight, and physical activity level.

Class="center">Table 26-14. The four basic food groups. A guide to their daily intake; foods within each group should be varied

Humans have always harbored irrational obsessions regarding food, endowing certain items with almost miraculous powers or placing strict taboos on others. Food choices are often determined by religious beliefs, as well as cultural or ethnic traditions. Moreover, folklore claims that certain foods are good for the Brain, others for Hair growth, and still others for reproduction. Even today, despite the high level of nutritional science, food prejudices and fads are not only widespread but sometimes even trendy, as seen with “organic,” “longevity,” or so-called Zen diets. Misconceptions about food are also frequently encountered. For instance, athletes are often advised to eat only protein-rich foods—such as meat, fish, and eggs—on the morning of a competition. However, the body cannot store Proteins, and they are not as efficient as CARBOHYDRATES as sources of energy. From a biochemist's perspective, it is much wiser to consume a large amount of carbohydrates before a competition to replenish Glycogen stores in The Liver and Muscles, as glycogen serves as the primary fuel during intense physical exertion.