FUNCTIONAL FOODS
In the recent past, there has been a great variety of foods that have been termed as superfoods or power foods. These foods have been said to have miraculous health benefits on human health. A more appropriate term coined for such foods is ‘Functional Foods’. The most common thing among these foods is that
- They are consumed mostly in their raw or minimally processed forms
- Any processing done is with utmost care to preserve their nutritional values.
- Therefore, the nutrients are intact within these foods
EC Concerted Action on Functional Food Science in Europe (FUFOSE) gave a working definition of functional food which states that:
- A food that beneficially affects one or more target functions in the body beyond adequate nutritional effects in a way that is relevant to either an improved state of health and well-being and/or reduction of risk of disease
- Not a pill, a capsule or any form of dietary supplement
- Consumed as part of a normal food pattern
Some such functional foods are:-
OATS. Oat products are a widely studied dietary source of the cholesterol-lowering soluble fiber b-glucan. There is now significant scientific agreement that consumption of this particular plant food can reduce total and low-density lipoprotein (LDL) cholesterol, thereby reducing the risk of coronary heart disease (CHD).
SOY. Soy has been in the spotlight during the 1990s. It is a high-quality vegetable source of protein and it is now thought to play preventive and therapeutic roles in cardiovascular disease (CVD), cancer, osteoporosis, and the alleviation of menopausal symptoms. Several classes of anticarcinogens have been identified in soybeans, including protease inhibitors, phytosterols, saponins, phenolic acids, phytic acid, and isoflavones. Of these, isoflavones (genistein and daidzein) are particularly noteworthy because soybeans are the only significant dietary source of these compounds. Isoflavones are heterocyclic phenols structurally similar to the estrogenic steroids. Because they are weak estrogens, isoflavones may act as antiestrogens by competing with the more potent, naturally-occurring endogenous estrogens for binding to the estrogen receptor.
FLAXSEED. Among the major seed oils, flaxseed oil contains the most (57%) of the omega-3 fatty acid, a-linolenic acid. Recent research, however, has focused more specifically on fiber-associated compounds known as lignans. The two primary mammalian lignans, enterodiol and its oxidation product, enterolactone, are formed in the intestinal tract by bacterial action on plant lignan precursors. Flaxseed is the richest source of mammalian lignan precursors. Because enterodiol and enterolactone are structurally similar to both naturally-occurring and synthetic estrogens and have been shown to possess weakly estrogenic and antiestrogenic activities, they may play a role in the prevention of estrogen-dependent cancers.
TOMATOES have received significant attention because of interest in lycopene, the primary carotenoid found in this fruit and its role in cancer risk reduction. Proposed mechanisms by which lycopene could influence cancer risk are related to its antioxidant function. The antioxidant function of lycopene may also explain the recent observation in a multi-center European study that adipose tissue levels of carotenoids were inversely associated with risk for myocardial infarction.
GARLIC. Garlic (Allium sativum) is likely the herb most widely quoted in the literature for medicinal properties. The purported health benefits of garlic are numerous, including cancer chemo-preventive, antibiotic, antihypertensive, and cholesterol-lowering properties. The characteristic flavor and pungency of garlic are due to an abundance of oil and water-soluble, sulfur-containing elements, which are also likely responsible for the various medicinal effects ascribed to this plant. However, intact, undisturbed bulbs of garlic contain only a few medicinally active components. The intact garlic bulb contains an odorless amino acid, alliin, which is converted enzymatically by allinase into allicin when the garlic cloves are crushed. This latter compound is responsible for the characteristic odor of fresh garlic. Garlic components have been shown to inhibit tumorigenesis.
BROCCOLI AND OTHER CRUCIFEROUS VEGETABLES Anti-carcinogenic properties of cruciferous vegetables have been attributed to their relatively high content of glucosinolates. Glucosinolates are a group of glycosides stored within cell vacuoles of all cruciferous vegetables. Myrosinase, an enzyme found in plant cells, catalyzes these compounds to a variety of hydrolysis products, which are suggested to have chemo-preventive properties, particularly of the mammary gland. Although a wide variety of naturally occurring and synthetic isothiocyanates have been shown to prevent cancer attention has been focused on a particular isothiocyanate isolated from broccoli, known as sulforaphane.
CITRUS FRUITS. Several epidemiological studies have shown that citrus fruits are protective against a variety of human cancers. Oranges, lemons, limes, and grapefruits are a principal source of important nutrients as vitamin C, folate, and fiber. Citrus fruits are particularly high in a class of phytochemicals known as the limonoids. Evidence has been accumulating in support of the cancer preventative effect of limonene
CRANBERRY. Cranberry juice has been recognized as efficacious in the treatment of urinary tract infections. This benzoic acid-rich fruit caused acidification of the urine. Recent investigations have focused on the ability of cranberry juice to inhibit the adherence of Escherichia coli to uroepithelial cells. This phenomenon has been attributed to two compounds: fructose and a nondialyzable polymeric compound.
TEA. Tea is second only to water as the most widely consumed beverage in the world. A great deal of attention has been directed to the polyphenolic constituents of tea, particularly green tea Polyphenols comprise up to 30% of the total dry weight of fresh tea leaves. Catechins are the predominant and most significant of all tea polyphenols. The four major green tea catechins are epigallocatechin-3-gallate, epigallocatechin, epicatechin-3-gallate, and epicatechin. By far, most research on the health benefits of tea has focused on its cancer chemopreventive effects. There is some evidence that tea consumption may also reduce the risk of CVD.
These are some of the most commonly known functional foods and newer ones are being identified regularity. Their health benefits are numerous and making them part of one’s daily diet regimen seems to be a good ‘FITNESS MANTRA’.
