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Chapter 13

13 NUTRITION

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The Community and Nutrition Programs

C onnections between nutrition and health have probably been understood, at least to some degree,

among all people of all places and times. For example, around 400 BC Hippocrates said, "Let food
be your medicine and medicine be your food." Understanding the physiological needs of our cells helps
us understand why it is that food has such an impact on overall health. In this chapter we introduce
nutrition by examining how cells use different nutrients and then discuss disease conditions that are
tied to nutritional problems.

Nutrition and Health in the Community

The nutritional status of people in our communities is a concern not only for quality of life, but
also for economics (treating illness costs far more than preventing it). Various public health agencies
are striving to prevent nutritional deficiencies and improve overall health. In the U.S., the government
supplies a variety of resources such as state assistance, WIC (Women Infant and Child), and so forth. In
addition, there have been many government agencies and voluntary health and scientific associations,
such as the American Heart Association, that focus on life style and dietary factors that prevent chronic
and life-threatening diseases. The U.S. Department of Agriculture (USDA) and the U.S. Department of
Health and Human Services (USDHHS) developed dietary guidelines in 1977 that were compiled and
displayed as the food guide pyramid. The food guide pyramid was revised as "My Pyramid," but this
new chart is confusing to most people. Harvard School of Public Health developed an alternative
healthy eating pyramid (shown at left) based on long-term nutritional studies. This pyramid differs
from the old USDA pyramid in several key aspects: for example, exercise is at the bottom to remind us
of its important role in our health. Also, not all carbohydrates are at the bottom (white bread, white rice,
and potatoes are now at the top with sugars), and not all oils are at the top (plant oils are at the bottom).
Other resource, such as the Recommended Daily Allowance (RDA) have helped people become more
aware of nutritional needs, yet obesity and chronic health problems continue to rise.

Nutritional Requirements

Our bodies have certain nutritional needs and if they are not met will cause catabolism of its own
fats, carbohydrates and proteins. Molecules are continuously broken down, so we must replace them.
Food molecules, essential fatty acids and essential amino acids are particularly important in replacing
these molecules. Vitamins (Vital Emines) and minerals are not used as energy, but are essential in
enzyme reactions. Living tissue is kept alive by using the expenditure of ATP, found in the break down
of food. Foods energy value is measured in kilocalories. 1 kilocalorie is equal to 1000 calories.

Carbohydrates

Macronutrient

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