HOEC 104 Life Span Nutrition & Assessment, Spring 2009

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2 There has been a dramatic increase in the sales of supplements in the United States since In 2003, 18.8 billion supplements were sold. Indeed, 46 percent of people polled from ages 14 to 19 indicated they used supplements. 2

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4 The DSHEA of 1994 ensured that the FDA would not have the same regulatory control over supplements that they do over prescription and over-the-counter medicines. Prior to that time, supplements were under similar regulations. Under the 1994 law, the supplement manufacturer must ensure that dietary supplements are safe before they are marketed. There are no provisions in the law for the FDA to approve dietary supplements for safety or effectiveness before they reach the consumer. 4

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7 Ephedra was banned after it was linked to several deaths, including that of Baltimore Orioles pitcher Steve Bechler in

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9 The Federal Trade Commission monitors the accuracy of advertising and labeling of supplements. They do not ensure the quality of supplements from manufacturer to manufacturer, or even between different batches of a product from the same manufacturer. 9

10 This slide presents an excellent opportunity for a class discussion. Ask students to think of examples of partially true claims, such as the example provided in the text regarding carnitine. 10

11 Here is another example of a partially true claim. DHEA does decrease with age. Research has suggested that DHEA is associated with decreased incidence of heart disease, various cancers, and several other age-related diseases. But whether or not a supplement can reverse the effects of aging is unclear. 11

12 Statistically, supplement use is highest in the following groups: women, people age 60 and older, whites, people with an education beyond high school, and those who exercise. Also, the higher one s BMI, the less likely one is to use a supplement. Use of supplements is common in athletes. This has led many athletic organizations, such as the IOC and NCAA, to ban some supplements to maintain fairness. Refer students to the text pages 312 and 313 listing permissible and banned substances or go to the organization s web site for an updated list. 12

13 Floyd Landis of the United States won the 2006 Tour De France. Shortly afterward, however, he was accused of doping and was stripped of his win. 13

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15 Worldwide revenues for Red Bull exceeded 1 billion in Since the product was launched in 1997, Red Bull s maker claims that its revenue has doubled each year. Many energy drinks provide more than the 80 mg of caffeine contained in one cup of coffee. By contrast, Mountain Dew has 37 mg per 12 oz and Coke has 23 mg. Individual responses to large doses of caffeine over time will vary, though the effects will be less prevalent in those who do not regularly consume these drinks. Many energy drinks are presented as being healthier than soda. See Table 11.1 for the caffeine content of popular drinks. 15

16 Most people take supplements to be healthier. They want to obtain the nutrients they think they are missing in their diets, though most studies show that those who take supplements get the nutrients they need from their food. Then there are those who take supplements because they hope for a quick fix or a magical cure. Many manufacturers, like the one whose ad is pictured here, pick up on the hopes of this last group and market their supplement to them. This business practice is especially disturbing when supplements are marketed to people who have HIV and cancer. See Table

17 See Make It A Practice. 17

18 Boron is a trace element found in the foods listed here. Limited research suggests that it influences calcium and magnesium metabolism, but it has no definitive function otherwise. Some people believe that it provides benefits for memory, menopausal symptoms, osteoarthritis, and more. However, there is no strong evidence that boron is beneficial for any of these. It is most widely marketed for its supposed ability to increase testosterone release, despite research that has discredited this claim. 18

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20 Chromium is a widely used supplement. It is sold either by itself or in combination with other supplements it is often found in supplements claiming to be fat burners. Chromium has been shown to be ineffective at increasing lean body mass, altering body composition, or improving strength. Even if it did what it claimed, most people get plenty from their diet. Chromium can be toxic at 6 to 12 times the recommended dose over the course of many months. It is considered safe if it is consumed in recommended quantities of 50 to 200 mcg per day. Vanadium is a trace mineral found in the foods listed here. It has no functional role, but several have been suggested. Vanadium may mimic insulin and would therefore help lower blood glucose in people with Type 2 diabetes. Animal studies have supported this claim, while human studies are promising but need more research. Vanadium is often marketed to athletes to enhance amino acid uptake, though it does not seem to work for this purpose. 20

21 Whey is a byproduct of cheese making. In its raw form it contains fat, lactose, and other substances. It is processed to produce whey protein concentrates (WPC) and whey protein isolates (WPI). WPC is rich in whey protein and contains some fat and lactose. WPIs are low in fat and lactose. Whey proteins may have antimicrobial functions, act as antioxidants, and aid the immune system. Whey proteins can be used as the sole protein in some infant formulas because they have been shown to result in fewer allergies in infants. Whey is not superior to soy, milk, or meat proteins in helping protein synthesis. People with milk allergies should avoid it. Arginine is conditionally essential. The typical American diet contains 3 to 6 g, mostly from plant proteins like soy. Normally, the body can make enough to meet its needs. However, people with certain genetic conditions and those who are recovering from burns or surgery cannot make enough arginine to meet their increased needs. Therefore, it is conditionally essential. Under normal circumstances, there is no benefit from supplementation. Aspartic acid is a non-essential amino acid used to make urea, proteins, glycogen, and energy. Its role in glycogen and energy production is the rationale behind the claim that supplemental aspartate has an anti-fatigue fatigue effect on skeletal muscle; this claim was never supported by research. 21

22 The optimum energy bar is equivalent to a food with 6 g of protein and 35 g of glucose. A glass of skim milk offers a similar amount. This slide represents information reported by Tipton et al. The timing of amino acid carbohydrate ingestion alters the anabolic response of muscle to resistance exercise (Am. J. Physiol. Endocrinol. Metab. 281(2): E ). 22

23 The branched chain amino acids are different from other amino acids, as they can be used directly by the muscle during exercise without going to the liver first. It has been suggested that ingesting them before and/or during long-duration exercise may help to delay fatigue, though studies have not strongly supported this claim. Branched chain amino acids do play a critical role in recovery from exercise by preventing muscle breakdown. They may improve immune system function after exhaustive exercise and benefit those who are experiencing rapid muscle breakdown, such as people dealing with HIV, cancer, AIDS, burns, and surgery. Furthermore, they may help those at risk of losing muscle loss as they age, though further research is needed to determine the extent of benefits and the dose needed. Glutamine can be obtained from food but it is made in the body already. It was initially classified as a non-essential but is now considered a conditionally essential amino acid because the body cannot produce enough during illness and stress. Glutamine is marketed in the sports supplements market with the promised effects of enhanced immune function, brain function, and digestion. Studies have reported shorter recovery times for trauma and cancer patients in doses of 20 to 30 g per day. The supplement may help boost immune function after prolonged endurance events, as prolonged endurance activity can impair the immune system. Also, although the evidence is not clear, glutamine may help athletes recover from extreme exercise. Glutamine is found in meat: A 3 oz serving of meat has between 3 to 4 g of it. It can also be found in milk, cheese, yogurt, peanuts, lentils, tofu, beans, and eggs. 23

24 Glucosamine and chondroitin have been widely promoted as useful for treating arthritis. Glucosamine is thought to stimulate the production and repair of cartilage. Chondroitin is a cartilage component thought to promote water retention and elasticity. Both compounds are produced in the body. Some research suggests that glucosamine may stimulate the production of cartilage-building proteins. Other studies suggest that chondroitin may inhibit production of cartilage-destroying enzymes and fight inflammation. While there have been some positive results, well-controlled long-term studies have not yet been conducted. No study so far has found any serious side effects from either glucosamine or chondroitin. You should take glucosamine sulfate rather than glucosamine hydrochloride, and do so for three months. If positive results are not experienced after this length of time, then the supplement probably is not going to work. Coenzyme Q10, also called ubiquinone, is a fat-soluble, vitamin-like substance made in the body. It is an antioxidant and serves as a coenzyme for several key enzymatic steps toward the production of energy within the cell. It is present in small amounts in a variety of foods, particularly beef, soy oil, sardines, mackerel, liver, and peanuts. In healthy individuals, id normal levels l are maintained i dby intake bodily production. Extravagant tclaims have been made for coenzyme Q10, many of which have not been supported by well-controlled studies. It is currently being tested for its ability to slow the progress of Parkinson's disease, boost stamina in AIDS patients, stabilize blood sugar levels in diabetics, enhance athletic performance, decrease allergies, and prevent retina deterioration that occurs with macular degeneration. Taking coenzyme Q10 in pill form may not provide any potential benefits, as it can lose its structure during digestion. There is evidence to indicate that coenzyme Q10 does work to support the heart, especially in congestive heart failure and angina (chest pain), at 100 to 200 mg per day. However, some studies show it is not effective. Due to inconclusive evidence, and the fact that long-term studies have not been conducted to test its safety and effectiveness, the American Heart Association does not recommend taking coenzyme Q10 for heart disease. Studies supporting the efficacy of coenzyme Q10 appear most promising for neurodegenerative disorders, such as Parkinson's disease. Several investigations have found improvements in athletic performance and antioxidant potential. In fact, ubiquinone supplementation (90 milligrams/day) was reported to improve aspects of physical performance in Finnish top-level cross-country skiers. Despite some promising results, experts are hesitant to recommend use until further studies are completed. Carnitine. Carnitine is the substance that transports fatty acids into the mitochondria for metabolism, so the thinking is as follows: more carnitine, more transport, and therefore more fat burned. The flaw in this thinking is that you already have all the carnitine you need, and more is not better. It s available in foods, and you readily synthesize it from amino acids. Carnitine supplements provide no performance advantage. 24

25 Creatine is made in the body and may be obtained in the diet, mostly from meat and fish. It is part of creatine phosphate, the key component of the immediate energy system, and is used primarily during sporting events lasting thirty seconds or less (such as track sprints). Higher intakes of creatine do seem to result in higher levels of creatine phosphate in the muscle cells, thus making more energy available for very high-intensity activity, such as strength training. The response depends on the frequency and type of training, as well as on the levels of creatine present in the body at the time supplementation begins. Vegetarians and other people who eat little creatine appear to have a greater response. Many people who have taken it complain of side effects, including headaches, abdominal cramps, and muscle cramps. Glycerol is part of triacylglycerols ygy (triglycerides gy or fats) and phospholipids. p p It is used as a sweetener in syrup, liquor, and some foods. Some believe that glycerol causes the body to hold more water so that you can sweat more before you become dehydrated. Thus, glycerol combined with water has been suggested to help prevent dehydration in endurance athletes who exercise in hot, humid environments. The results of research regarding glycerol s effect are varied; one study showed that pre-exercise intake of glycerol significantly improved cycling endurance time and lowered the average heart rate. However, another study of triathletes showed that pre-exercise consumption of glycerol failed to enhance performance. The results may have differed because the athletes used different amounts of glycerol and water. Consuming 1 g of glycerol per kg of body weight with 1 to 2 liters of water may help prevent heat illness. It is still unclear whether glycerol supplementation is superior to sports drinks in preventing dehydration, as the side effects include abdominal cramps, bloating, and nausea. HMB is a product of the breakdown of the essential amino acid leucine. It is synthesized naturally in humans and is available in some foods (e.g., citrus fruits and catfish). Whether HMB has a necessary physiological function or is merely a product of leucine breakdown remains unclear. HMB is marketed to prevent muscle breakdown associated with resistance training, to enhance strength, and to decrease body fat. Because of its supposed uses, HMB has become a popular nutritional supplement among body builders and strength trainers, and is often recommended along with creatine supplementation. As is typical with many supplements sold for muscle building, the marketing hype exceeds the supporting evidence from research. So, unfortunately, any claims that it does what it is marketed to do are just that, claims. 25

26 Caffeine is one of the most widely used drugs in the world. In some supplements it is listed as guarana or kola nut. It can be found in coffee, tea, chocolate, soft drinks, some pain relievers such as Excedrin, some cold medicines, and in many weightloss pills. Caffeine is sometimes used as a nervous system stimulant to offset fatigue, and during the 1990s it was thought to benefit the endurance of athletes because it was shown to help release fat stores into the bloodstream. Unfortunately, more fat in the blood does not translate into more fat utilization by muscle. Studies have shown that caffeine alone, or caffeine combined with ephedra, does increase performance by delaying fatigue or increasing the time it takes to reach exhaustion in endurance exercise. Increases in endurance performance have been shown to occur after consuming doses of 3 to 9 mg per kg of body weight. People who consume caffeine on a daily basis can become tolerant and may have to use more caffeine to get the same effect. Caffeine does have some side effects. People who do not regularly consume caffeine can experience gastrointestinal distress, nervousness, rapid heart rate, headaches, and increased blood pressure. In addition, caffeine can have a diuretic effect, but this is usually most pronounced during rest and does not appear to have as large an effect during exercise. 26

27 Consumers spend about $38 billion annually on weight-loss products. People desperate to lose weight are especially vulnerable to advertisements claiming easy, quick results. Several consumer groups have sought to protect and warn consumers about such false claims and inform them of new tactics used to appeal to the vulnerable. 27

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29 Black cohosh is a member of the buttercup family. It is also called black snakeroot, macrotys, bugbane, bugwort, rattleroot, and rattleweed. It has a history of use for rheumatism (arthritis and muscle pain), but more recently has been used to treat postmenopausal symptoms such as hot flashes, night sweats, and vaginal dryness. Additionally, it has been used to ease the effects of menstrual irregularities and premenstrual syndrome, and to induce labor. As with so many other supplements, there is no scientific evidence to support its effectiveness, or to indicate whether it is safe. Historically, cranberry fruits and leaves have been used for a variety of problems, such as treating wounds, urinary disorders, diarrhea, diabetes, stomach ailments, and liver problems. More recently, cranberry products have been used to prevent or treat urinary tract infections, helicobacter pylori infections that can lead to stomach ulcers, and dental plaque. Cranberries have also been reported to have antioxidant and anticancer properties. Although not conclusive, promising preliminary results do suggest that cranberry products could be used to prevent and treat urinary problems. Side effects from their consumption are minimal and include diarrhea and minor upset stomach. 29

30 Echinacea: Believed to prevent colds, as well as reduce their symptoms and duration. It is difficult to determine whether echinacea really works as suggested because preparations available on the market vary significantly. Studies investigating whether taking echinacea preparations for eight to twelve weeks prevents colds have been conducted, but the results show no clear effect. Other research has focused on whether taking echinacea preparations after the onset of cold symptoms shortens the cold s duration or decreases its severity. It seems that some preparations, based on the herb echinacea purpurea, might be effective for this purpose in adults, while the evidence remains unclear regarding the effectiveness of other preparations, or whether children may benefit. Echinacea seems to be nontoxic, but it is suggested that it not be used for longer periods than eight weeks due to a loss of effectiveness. Although it currently seems safe when taken as a supplement, caution should be taken: Allergic reactions can occur, especially in people who are allergic to related plants in the daisy family, such as ragweed, chrysanthemums, and marigolds. Garlic: It has grown in popularity due to associated decreases in cholesterol and its ability to help control blood pressure. Garlic has also been shown to have potential anticancer effects. It belongs to the allium vegetable family, along with onions, ginger, scallion, leeks, and chives. As a result, these food items have many of the same beneficial compounds as garlic. It is unclear whether odorless supplements have the same benefits as natural garlic. The most dangerous side effect associated with garlic supplementation is the risk of bleeding. Therefore, supplementation should be discontinued prior to any surgical procedure, and is not advisable for people who take anticoagulants or blood thinners. 30

31 Ginkgo: Used for treatment of various conditions, including memory and concentration problems, confusion, depression, anxiety, dizziness, ringing in the ears, and headache. Ginkgo is thought to increase blood flow by dilating blood vessels and decreasing blood thickness. It is also supposed to modify neurotransmitter systems and reduce oxygen-free radicals. Early studies strongly supported the use of ginkgo for mental functioning. More studies need to be conducted, but at this time there do not appear to be any severe side effects at doses of less than 200 mg per day. Ginseng: A lot of claims have been made about ginseng, but it is most commonly sold to improve overall health and boost the immune system. Research conducted to date is still inconclusive. NCCAM is studying ginseng s interaction with other herbs and drugs and its potential to treat chronic lung infection, impaired glucose tolerance, and Alzheimer's disease. Other studies are exploring whether ginseng may lower blood sugar levels; if so, it may benefit diabetics. However, people with diabetes should use extra caution when taking ginseng, especially if they are using medicines or taking other herbs to lower blood sugar. Side effects are rare but have been reported. They include headache, gastrointestinal upset, breast tenderness, menstrual irregularities, and high blood pressure. The difficulty in identifying side effects ec is that ginseng g is often added to other products, such as teas and energy drinks, making it difficult to determine whether the side effect is from the ginseng or from other ingredients in the product. Yohimbine: Best known as an aphrodisiac. This conclusion is based primarily on testimonials, as its true effect on the sex drive of humans has not been properly demonstrated. However, for more than seventy years, yohimbine has been used to treat male sexual difficulties. The use of yohimbine is based on evidence from studies using the prescription drug yohimbine hydrochloride, which does appear to effectively treat male impotence. The supplemental form is made from the bark and, although yohimbine is present in yohimbe bark extract, levels are variable and often very low. Safety has not been evaluated scientifically, but many adverse side effects have been reported, such as excessive sweating, facial flushing, increased heart rate and blood pressure, restlessness, irritability, shakes, and increased anxiety. 31

32 Ginger: Used in the relief of nausea, vomiting, and motion sickness. It has also been reported to have anti-inflammatory properties and, although the evidence is still inconclusive, it may be effective in relieving morning sickness during pregnancy. St. John's Wort: Has been used for centuries to treat mental disorders as well as nerve pain. Today, St. John's Wort is used to treat mild-to-moderate depression, anxiety, and sleep disorders. The major benefits of St. John s Wort are that it costs less than prescription medications for depression and typically does not produce the undesirable side effects shown by conventional antidepressive drugs. Results from several studies have supported the effectiveness of certain St. John's Wort extracts for depression. It is best used to treat mild depression. Valerian: Used as a mild sedative and sleeping agent. Studies conducted on the effectiveness of valerian for insomnia have been poorly controlled and, therefore, are inconclusive. To date, no adverse side effects have been reported in humans. 32