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Complementary Nutrition: Functional Foods and Dietary Supplements. BIOL 103, Chapter 3. Today ’ s Topics. Functional Foods Phytochemicals Food Additives Types & Regulations Dietary Supplements: Vitamins and Minerals Natural Health Products Regulations and Claims
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Complementary Nutrition: Functional Foods and Dietary Supplements BIOL 103, Chapter 3
Today’s Topics • Functional Foods • Phytochemicals • Food Additives • Types & Regulations • Dietary Supplements: • Vitamins and Minerals • Natural Health Products • Regulations and Claims • Complementary and Alternative Medicine
Functional Foods • What is it? • Functional foods: a food that may provide a health benefit beyond basic nutrition. • Foods can be classified as functional foods if they contain: • naturally-occurring phytochemicals • “vitamins, bacteria, fiber, etc.” – fortification
Phytochemicals • Phytochemicals are substances that have health benefits, but they may not be essential to life • makes food functional • act as Antioxidants • Neutralize free radicals • Reduce heart disease and cancer risk • Found naturally in fruits, vegetable, whole grain, legumes, and wine
Examples and Benefits of Phytochemicals (PS#3, Q1) • Table 3.1: Examples of Functional Components • Lycopene(prostate health) • Omega-3 fatty acids (heart, mental and visual function) • Isoflavones/soy products (bone, brain, immune system, menopause) • Probiotics(gut health, immune system) • Flavonoids(cellular antioxidants defenses)
Foods Enhanced with Functional Ingredients • Foods can be enhanced with functional ingredients during processing
Speaking of antioxidants… What is an antioxidant?
What is a free radical and what does it do? • While the body metabolizes oxygen, 1-2% of cells will get damaged in the process turn into free radicals (“active oxidants”) • Normally, free radicals oxidize/damage; this may lead to chronic diseases: • DNA, cell structures cancer and cell aging • Lipids heart disease
Formation of Free Radicals Cellular and environmental factors can cause free radicals to form Free radicals can DNA damage
How do phytochemicals work to prevent chronic disease? • Phytochemicals such as flavonoids provide antioxidant effects • By neutralizingfree radicals, antioxidants can
How do phytochemicals work to prevent chronic disease? • Phytoestrogen or “dietary estrogen” is a type of phytochemical with estrogenic/anti-estrogenic effects. • Phytoestrogens either modify estrogen metabolism or block effect of estrogen on cell growth
Regulatory Issues for Functional Foods • To monitor the products for consumption, FDA categorizes into the following: • [Conventional] Food include: • the product that we eat/drink • components that make up the product. • Drug: substance intended to diagnose, cure, mitigate, treat, prevent disease • Dietary Supplements: products meant to supplement a diet, but are not conventional foods. • “Food Additives”
Food Additives(PS#3, Q2) • Additives: substances added to food for various functions • 2 types of additives: • Direct • Indirect
5 Purposes of Direct Additives • Maintain product consistency • Improve or maintain nutritional value • Keep food appetizing and wholesome • Provide leavening or control acidity and alkalinity (e.g. yeast, baking powder, baking soda) • Enhance flavor or color
Alcohol Metabolism Vitamins as Food Additives in Alcohol?
Enhanced Alcoholic Beverages What’s the idea behind it? Why no advertising? For chronic, heavy drinkers vitamin toxicity (e.g. too much B6 = neurological symptoms) • Vodka/Beer + Vitamin B – in hopes of speeding up the metabolism via Vitamin B alcohol is processed faster reduced chance of a hang-over
Regulation of Food Additives by the FDA • Additives fall into 4 Regulatory Categories: • Food Additives • Color Additives • Generally Recognized as Safe (GRAS) substances • Prior-sanctioned substances
Regulation of Food Additives by the FDA (PS#3, Q3) • Food Additives • Must have FDA approval • Manufacturermust prove safety • Color Additives:any dye/pigment or other substance that can impact color when added to a food, drug, cosmetic, or to a human body. • Certified color additives used in foods are man-made.
Who loves Orange Juice? • Processed orange juice is generally flavorless because oxygen is removed from them (prevents spoiling) • So, juice companies hire flavor and fragrance companies to make flavor packs to make the juice taste fresh. • Flavor packs are not listed in ingredient labels b/c they are technically derived from orange essence and oil. • Different fragrance chemicals are used in different countries
Regulation of Food Additives by the FDA (PS#3, Q4) 3. Generally Recognized as Safe (GRAS):substances that can be added to foods by manufacturers without establishing rigorous scientific tests. • “additives that are generally thought by experts to be safe to eat” • e.g. salt, sugar, spice, MSG… 4. Prior-sanctioned Substances: substances that FDA and/or USDA determined were safe to use in specific foods before Sept 1958.
MSG • MSG: monosodium glutamate • What is it? • Flavor enhancer found in many Asian cuisine, canned vegetables, processed meat. • Is it really harmful? • People report short-term side effects such as headache, flushing, sweating, nausea, chest pain… • What does the research say? • Researchers have yet to find a solid evidence that link these symptoms with MSG. However, because MSG topic is still controversial, the FDA requires that MSG is listed in the labels.
Delaney Clause (PS#3, Q4) • Delaney Clause: food and color additives cannot be approved if they cause cancer in humans or animals. • Agree or Disagree? • Controversy associated with amount tested in animals vs. actual human consumption
Strategies for Functional Food Use • Stick with science • Eat fruit and vegetables • Eat nutrition-fortified products as needed • Read, read, read (scientific articles) • Be critical of advertising and hype • “if it sounds too good to be true, it probably is!”
Dietary Supplements: Vitamins and Minerals • Various forms of dietary supplements: • Examples: Vitamins, minerals, amino acids, herbs, glandular extracts, enzymes, etc. • 2 levels of vitamin and mineral supplementation: • Moderate doses: within the range of the Daily Values (DVs) • Megadoses: high levels beyond DVs
Who should seek moderate supplementation? • Those with increased nutrient needs and/or poor intake include: • Women of childbearing age who may become pregnant • Pregnant and breastfeeding women • Women with heavy menstrual losses • Children (picky eaters)
Who should seek moderate supplementation? • People with severe food restriction • Strict vegetarians who do not eat animal foods and dairy products • Elderly
When looking for moderate supplementation… • If you are looking for moderate supplementation: • Look for brands that contain at least 20 vitamins and minerals • No more than 100% of its DV
Megadoses in Conventional Medical Management • Situations in which doctors are likely to prescribe megadoses: • Treatment of severe deficiencies • Malabsorption syndromes: when individual cannot absorb enough nutrients in their gut. • Drug interactions • A vitamin at megadose levels can have “drug-like effects,” thus, patients may suffer serious side-effects. • Example: Niacin at 100x the usual level can act as a drug to lower blood lipid levels.
Megadosing Beyond Conventional Medicine: Orthomolecular Nutrition • Orthomolecular medicine: the preventive or therapeutic use of high-dose vitamins to treat a disease. • Linus Pauling, 1968 • Achieving the “optimal nutrition” levels • Q: Does consuming a lot of Vitamin C prevent cold?
Drawbacks of Megadoses(PS#3, Q5) • Can act as a drug adverse side effects • Can create deficits of other nutrients by interfering with absorption of others • Nutrient-nutrient interactions: Zn, Fe, Cu, Ca • Can interfere with functions of other nutrients • Ex: Megadoses of Vitamin E interferes with blood clotting functions of Vitamin K • In general, more dangerous to megadose with minerals than vitamins
Dietary Supplements: Natural Health Products • Natural health products • Used in Herbal therapy (phytotherapy) • Little scientific evidence of efficacy, safety • All foods are made up of chemical components • Advertisements use “100% Natural” (2nd highest claim on food labels, 2008). • The general American consumer believes that natural foods are more “wholesome, nutritious, and healthy.” • Traditional Herbalists vs. Conventional Medicine
Helpful Herbs, Harmful Herbs • NCCAM and NIH mission: to investigate using science to make sure herbs, herbal therapy and related practices are safe and healthy • Main idea: “if strong enough to help, strong enough to hurt” • Not all herbs are good for you • Poor quality • Too much herbs may cause negative effects • Herbs may interact with doctor prescribed medicines • Table 3.5 Herb-Drug Interactions
Dietary Supplement in the Marketplace • Manufacturers have freedom of speech and press. • Thus, they are allowed to to a wide variety of claims for product effects without having to provide scientific evidence to support those claims.
FTC and Supplement Advertising • FTC (Federal Trade Commission)is responsible for ensuring that advertisements and commercials are truthful and do not mislead. • Depends on and encourages self-monitoring by the supplement industry • FTC’s “Operation and Cure All”– online version, to search for false claims about the supplement
FDA and Supplement Regulation • FDA has primary responsibility for regulating labeling and content of dietary supplements under 1994 Dietary Supplement Health and Education Act (DSHEA) • So how do you know if it’s a dietary supplement? • Dietary supplements: “products that are taken by mouth that contain a dietary ingredient.”
The FDA and Supplement Regulation(PS#3, Q6) • Dietary supplements and their ingredients are NOT drugs and are NOT additives. • Drugs require extensive tests for safety, effectiveness, dosing, etc., BEFORE and AFTER marketing. • Food additives also require approval BEFORE marketing • Supplement approval by FDA is not required • Thus, FDA must prove it isn’t safe AFTER it is on the market…
Supplement Labels Mandatory requirements are: Name of Dietary Supplement Amount of dietary supplement Nutrition Labeling The Ingredient List Name and place of business of the manufacturer, packer, or distributor.
Dietary Supplements and Claims • Health claims (associated with disease/health condition) • Structure/functional claims • Must have “disclaimer” statement on label: “this statement has not been evaluated by the FDA.” • Nutrient content claims • Consistent with definitions approved for foods
Choosing Dietary Supplements • Ask the following questions: • Is the quantity enough to have an effect? • Is the product new to you? • What is its bioavailability? • There is little data on bioavailability of herbal preparations and other types of non-nutrient supplements.
Choosing Dietary Supplements • Ask the following questions (cont.): • Can it interact with any prescription or other medications you are taking? • Does the product promise too much? • Who is selling the product? • Multilevel marketing: system of selling in which each salesperson recruits assistants who then recruit others to help them. The person at each level collects a commission on sales made by later recruits.
Choosing Dietary Supplement • U.S. Pharmacopea (USP) is a verification mark that verifies: • Contains ingredients declared on the label • Contains the amount or strength of ingredients declared on the label • Meets requirements for limits on potential contaminants • Has been manufactured properly by complying with USP and FDA manufacturing standards
Fraudulent Products • ~1/3 of herbal supplements on the market may be outright fraudulent. • Remember, dietary supplements, unlike foods and drugs, are not reviewed/tested to be effective by the FDA. • Examples of potential warning signs: • Claim to be alternatives to FDA-approved drugs • Claim to be legal alternative to steroids • Marketed primarily in a foreign language/mass emails
Complementary and Alternative Medicine (CAM) • Complementary and Alternative Medicine (CAM): therapies and treatment outside the medical mainstream. • Alternative practices used in place of conventional medicine. • Complementary practices used in addition to conventional medicine. • 40% adults and 12% children in America use some form of CAM therapy.
CAM and Nutrition • Alternative nutrition practices include diets to prevent and treat diseases not shown to be diet-related • Usually alternative nutrition practices are: • Overly restrictive • Depart from established guidelines (My Plate) • Lack rigorous scientific evidence • Reliance on raw foods, herbal/botanical supplements, megadoses of vitamin/mineral supplements
CAM and Nutrition • Nutrition in CAM • Vegetarian diets (alternative) • When individual go “meatless” to treat a disease • Macrobiotics diet (alternative) • Emphasizes fresh and unprocessed food, low-fat, whole grains, vegetables, and less fluids.
Food Restriction and Food Prescriptions • Many societies use dietary changes to treat or prevent illness • The treatments are different diets are based on cultural factors than science. • Fad diets most often eventually fail because they do not work. • The few that prove effective and have a scientific basis become integrated into conventional nutrition and diet therapy.