Functional Foods

Functional foods are conventional foods conferring additional health benefits in addition to providing energy necessary for the body's function. Other terms associated with these foods include designer foods (containing cancer or disease preventive properties), phytochemicals (pharmacologically active food components), pharmafoods, and nutraceuticals (more often dietary supplements made from plant or animal products). The Food and Drug Administration (FDA) regulates the labeling of conventional foods and enriched or enhanced foods for health claims or structure function claims by evaluating the claims of potential health benefits with scientific evidence. This began in 1997 when the FDA ruled oatmeal could claim to be heart healthy.

Health claims relate food or food components to disease or health conditions and are limited to risk reduction and not cures, treatments, alleviation, or prevention. An example of a health claim is low-sodium diets may reduce the risk of high blood pressure.

Functional foods are essentially foods that provide an additional benefit to the body beyond simply supplying energy.

Structure function claims relate food or food components to normal structure and function of the body and must be truthful and derived from nutritional value. An example of a structure function claim is calcium builds strong bones.

Nutrition professionals recommend a variety of foods in adequate quantities to provide for energy requirements and provide essential nutrients, those vitamins, minerals, and amino acids not produced in the body. Appropriate diet options in the 2005 Dietary Guidelines for Americans include recommendations to maintain a healthy body weight and reduce risks of chronic diseases (cardiovascular, cancer, diabetes). Functional foods may reduce health risks commonly associated with obesity—hypertension, diabetes, hyperlipidemia, coronary artery disease, and some cancers. Because of [Page 304]the complex nature of nutrients in food and the factors of many components working together to promote health, health claims may be difficult to establish.

Current trends in scientific research of functional foods are aimed at determining the validity of common health claims and analyzing the components of foods for nutritional and health benefits. In general, for a study to be of use in substantiating health claims for functional foods, they should have a large enough sample size with a control group and sufficient duration. The findings should be consistent with or supported by other research.

When evaluating the research performed and used to substantiate a claim, additional factors are important including the sponsor of the research to ensure the information is credible, whether the researcher objective is to sell a specific product, and whether the information is current to keep pace with advances in medicine, science, and nutrition.

Some foods have become mainstays of functional foods for their component properties. Fiber has been shown to reduce feeling of hunger by providing bulk with low calories and may help to decrease blood sugar and cholesterol levels. Two kinds of fiber—soluble and insoluble—have different functions. The soluble fiber found in beans, oatmeal, and apple skin may retard nutrient absorption rates. The insoluble fiber found in bran and whole grains increases intestinal transit and has benefits against colon cancer.

Live active cultures or probiotics in yogurt may prevent gastrointestinal infections and colon cancer, boost the immune system, and reduce allergies. Phytoestrogens—for example, soy, whole wheat, seeds, grains, some vegetables, and fruits—may prevent hormone-related cancers of the breast and prostate, lower cholesterol and prevent memory loss, and possess antiinflammatory and antioxidation properties. Cranberries in foods or in juice for preventing and treating urinary tract infections have been studied and have been in common use for some time. Other research indicates possible reduction in dental plaque as well as anticancer and antioxidant activity. Antioxidants have received much press. As a group, antioxidants scavenge free-radicals created by oxygen-powered metabolism; the by-product is a reactive oxygen species capable of damaging cells. Antioxidants include flavonoids or polyphenols, carotenoids, and omega-3 fatty acids.

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