Presentation on theme: "Phytochemicals Presented by Janice Hermann, PhD, RD/LD OCES Adult and Older Adult Nutrition Specialist."— Presentation transcript:
Phytochemicals Presented by Janice Hermann, PhD, RD/LD OCES Adult and Older Adult Nutrition Specialist
Phytochemcials and Functional Foods Foods contain many different nutrients: Carbohydrates Fiber Lipids Proteins Vitamins Minerals
Phytochemicals and Functional Foods Plant foods also contain non-nutrient compounds including – phytochemicals Phytochemicals are compounds in foods that physiological activity in the body
Phytochemicals and Functional Foods Concept that foods provide health benefits beyond those provided by the major nutrients has developed from numerous epidemiological studies demonstrating a protective effect of plant foods on cancer and heart disease.
Phytochemicals andFunctional Foods Although current research is discovering the beneficial roles of phytochemicals have in human health. Only a few of the tens of thousands of phytochemicals have been researched, and there are still many questions and only indefinite answers.
Phytochemicals and Functional Foods Concept foods provide health benefits beyond those of nutrients initiated name “functional foods" Nature’s functional foods Grains rich in dietary fibers Fish rich in omega-3 fatty acids Fruits, vegetables and legumes rich in phytochemicals and fiber Newest controversies is the development of novel foods to which phytochemicals have been added to promote health.
Phytochemicals and Functional Foods Phytochemicals can have profound physiological effects in the body, functioning as: Antioxidants Mimicking hormones Suppressing the development of diseases
Example Phytochemicals Carotenoids in deeply pigmented fruits and vegetables (apricots, broccoli, cantaloupe, carrots, pumpkin, spinach, sweet potatoes, tomatoes) act as antioxidants possibly reducing risk of cancer and other diseases. Curcumin in tumeric may inhibit enzymes that activate carcinogens
Example Phytochemicals Flavonoids in berries, black tea, celery, citrus fruits green tea, olives, onions, purple grapes, purple grape juice, soy beans and soy products, vegetables, whole wheat, and wine act as antioxidants, scavenge carcinogens, bind to nitrates in the stomach preventing conversion to nitrosamines, and inhibit cell proliferation.
Example Phytochemicals Indoles in broccoli and other cruciferous vegetables and mustard greens may trigger production of enzymes that block DNA damage from carcinogens and may inhibit estrogen action. Isothiocyanates in broccoli and other cruciferous vegetables and mustard greens inhibit enzymes that activate carciongoens, trigger production of enzymes that detoxify carcinogens.
Example Phytochemicals Lignans in flaxseed and whole grains block estrogen activity in cells. Monoterpenes in citrus fruit peels and oils may trigger enzyme production to detoxify carcinogens; inhibit cancer promotion and cell proliferation Organosulfur compounds in chives, garlic, leeks, and onions may speed production of carcinogen destroying enzymes, slow production of carcinogen activating enzymes.
Example Phytochemicals Phenolic acids in coffee beans, fruits, oats, potatoes, and soybeans may trigger enzyme production to make carcinogens water soluble facilitating excretion. Phytic acids in whole grains binds to minerals, preventing free-radical formation. Phytoestrogens (genistein and daidzein) in soybeans and other legume products mimic estrogen and may inhibit estrogen
Example Phytochemicals Protease inhibitors in broccoli, potatoes, soy beans and other legumes may suppress enzyme production in cancer cells, slowing tumor growth, inhibit hormone binding and inhibit malignant changes in cells. Phytosterols in soybeans and other vegetables may protect against heart disease by inhibiting cholesterol absorption
Example Phytochemicals Saponins in alfalfa sprouts, green vegetables, potatoes and tomatoes may interfere with DNA replication, preventing cancer cells from multiplying and stimulate immune response. Tannins in black-eyed peas, grapes, lentils, red and white wine and tea may inhibit carcinogen activation and cancer promotion and act as antioxidants.
Protecting Against Cancer Many phytochemicals from many different foods seem to protect against cancer by preventing DNA damage. Soybeans, flaxseed oil, whole grains, fruits, and vegetables are rich sources of phytochemicals, including phytoestrogens. Phytoestrogens weakly mimic or modulate the effects of estrogen in the body. Phytoestrogens have antioxidant activity and seem to slow the growth of breast and prostate cancer.
Protecting Against Cancer Tomatoes appears to protect against esophagus, lung, prostate, and stomach cancers. Lycopene is found in apricots, guava, papaya, pink grapefruits, watermelon, and it is especially abundant in tomatoes and cooked tomato products. Lycopene is a powerful antioxidant that appears to inhibit the growth of cancer cells.
Protecting Against Cancer Soybeans and tomatoes are examples of only two of the many fruits and vegetables attributed with protecting against cancer. Researchers hypothesize that people may cut their risk of cancers in half by simply consuming the recommended amounts of fruits and vegetables daily.
Protecting Against Heart Disease Diets rich in whole grains, vegetables and fruits also appear to lower risk of heart disease. These foods provide an abundance of nutrients, fiber, and phytochemicals.
Protecting Against Heart Disease Flavonoids - large group of phytochemicals that may protect against heart disease. Flavonids found in whole grains, legumes, soy, vegetables, fruits, herbs, spices, teas, chocolate, nuts, olive oil, and red wines. Flavonoids are strong antioxidants that may help to protect LDL cholesterol against oxidation and reduce blood platelet stickiness, making blood clots less likely.
Protecting Against Heart Disease In addition to flavonoids, fruits and vegetables are rich in carotenoids. Diets rich in carotenoids is also associated with a lower risk of heart disease. Two carotenoids that may defend against heart disease are lutein and lycopene.
Protecting Against Heart Disease Phytosterols found in soybeans and other vegetables appear to protect against heart disease. Phtosterols are similar in structure to cholesterol and inhibit the absorption of cholesterol decreasing blood cholesterol levels. Phytoestrogens may also protect against heart disease by functioning as antioxidants and lowering blood pressure.
Phytochemicals in Perspective Because foods deliver thousands of phytochemicals in addition to dozens of nutrients, consumers must be careful in giving credit for particular health benefits to any one compound. Diets rich in whole grains, legumes, vegetables, and fruits seem to be protective against disease, but identifying the specific foods or components of foods that are responsible is difficult.
Phytochemicals in Perspective Foods contain many phytochemicals. Broccoli may contain as many as 10,000 different phytochemicals Each with the potential to influence some action in the body. The effect of different phytochemicals in food may be synergistic. This reinforces the principle of variety.
Oklahoma Cooperative Extension Service Functional foods... from nature from manufacturers
Functional Foods Because foods naturally contain thousands of phytochemicals, whole foods, in reality, are functional foods. Cranberries may help protect against urinary tract infections Garlic may help ower blood cholesterol; and tomatoes may protect against certain types of cancers
Functional Foods In addition to naturally occurring functional foods, food manufacturers are trying to create functional foods as well – becoming the fastest growing trend in the food supply. Foods may be fortified or enhanced with nutrients, phytochemicals or herbs Sometimes an entirely new food is created
Foods or Drug? Such functional foods raise the question – is it a food or drug? In the past, most could agree what was a food and what was a drug. Functional foods have distorted the distinctions. Functional foods have characteristics of both foods and drugs, but do not fit clearly into either category.
Foods or Drug? For example, yogurt contains Lactobacillus and other living bacteria that ferment milk into yogurt. These microorganisms, called probiotics, alter the gastrointestinal population of microorganisms, which protects the gastrointestinal tract against disorders.
Foods or Drug? Research is investigating whether probiotics: Help to alleviate diarrhea, inflammatory bowel disease, and lactose intolerance Enhance immune function Protect against gastrointestinal cancer Lower blood cholesterol
Food or Drug? An example of where food manufactures are developing products with added phytochemicals is margarine. Consuming nonhydrogenated margarine sparingly may lower blood cholesterol slightly over several months and falls clearly falls into the category of a food. Whereas, the drug Lipitor lowers blood cholesterol significantly within weeks and clearly falls into the category of a drug.
Food or Drug? Consider, margarine enhanced with the phytosterol. Phytosterol is a phytochemcial that is structurally similar to cholesterol, and has been found to lower blood cholesterol levels by inhibiting cholesterol absorption. Margarine enhanced with phytoserol falls between the categories of a food and drug.
Food or Drug? Use of functional foods to result in beneficial effects results in a whole new set of diet- planning problems. Just as drugs, functional foods may need to be consumed several times a day for several months or years to have beneficial effects. Sporadic use may have disappointing results.
Food or Drug? For example: Margarine with added phytosterols consumed four times a day for four weeks lowered cholesterol by 8 percent. But cholesterol lowering drugs lowered cholesterol by 32 percent. Functional foods may be more useful for prevention and mild disease cases than for intervention and more severe
Cost Differences There may also be a difference in cost as well. Functional foods such as fruits and vegetables have no added costs Foods manufactured with added phytochemcials can be expensive, costing much more than their conventional counterparts
Unanswered Questions To achieve a desired health effect, which is the better choice: to eat a food designed to affect some body function or simply to adjust the diet? Does it make more sense to use a margarine enhanced with a phytosterol that decreases cholesterol absorption, to consume foods naturally high in phytosterol or limit the amount of saturated fat in the diet?
Unanswered Questions One concern is that the food industry moves too fast for science and the FDA to keep up. Consumers were able to modified foods while research is still being conducted as to the safety and efficacy.
What Should Consumers Think Does it work? Research is generally lacking and inconclusive How much does it contain? Research is lacking as to what level is effective or dangerous Is it safe? Functional foods can act like drugs, they contain ingredients that can alter body functions. Is it healthy? Adding phytochemcials to a food doesn’t magically make it a healthy choice
What Should Consumers Think Researchers have not identified the perfect combination of nutrients and phytochemciasl for optimal health. Yet food manufacturers are freely adding various phytochemicals to foods.
What Should Consumers Think Important to remember foods naturally provide a variety of nutrients and non- nutritive compounds that may be beneficial to health, most of which have yet to be identified or understand. A well balanced diet, from a variety of foods can in itself provide the variety of nutrients and non-nutrients for health and well-being.