Items in AFP with MESH term: Dietary Supplements
Ergogenic Aids: Counseling the Athlete - Article
ABSTRACT: Numerous ergogenic aids that claim to enhance sports performance are used by amateur and professional athletes. Approximately 50 percent of the general population have reported taking some form of dietary supplements, while 76 to 100 percent of athletes in some sports are reported to use them. Physicians can evaluate these products by examining four factors (method of action, available research, adverse effects, legality) that will help them counsel patients. Common ergogenic aids include anabolic steroids, which increase muscle mass. These illegal supplements are associated with a number of serious adverse effects, some irreversible. Creatine modestly improves athletic performance and appears to be relatively safe. Dehydroepiandrosterone and androstenedione do not improve athletic performance but apparently have similar adverse effects as testosterone and are also banned by some sports organizations. Caffeine has mild benefits and side effects and is banned above certain levels. Products that combine caffeine with other stimulants (e.g., ephedrine) have been linked to fatal events. Protein and carbohydrate supplementation provides modest benefits with no major adverse effects.
ABSTRACT: From 2 to 10 percent of women of reproductive age have severe distress and dysfunction caused by premenstrual dysphoric disorder, a severe form of premenstrual syndrome. Current research implicates mechanisms of serotonin as relevant to etiology and treatment. Patients with mild to moderate symptoms of premenstrual syndrome may benefit from nonpharmacologic interventions such as education about the disorder, lifestyle changes, and nutritional adjustments. However, patients with premenstrual dysphoric disorder and those who fail to respond to more conservative measures may also require pharmacologic management, typically beginning with a selective serotonin reuptake inhibitor. This drug class seems to reduce emotional, cognitive-behavioral, and physical symptoms, and improve psychosocial functioning. Serotoninergic antidepressants such as fluoxetine, citalopram, sertraline, and clomipramine are effective when used intermittently during the luteal phase of the menstrual cycle. Treatment strategies specific to the luteal phase may reduce cost, long-term side effects, and risk of discontinuation syndrome. Patients who do not respond to a serotoninergic antidepressant may be treated with another selective serotonin reuptake inhibitor. Low-dose alprazolam, administered intermittently during the luteal phase, may be considered as a second-line treatment. A therapeutic trial with a gonadotropin-releasing hormone agonist or danazol may be considered when other treatments are ineffective. However, the risk of serious side effects and the cost of these medications limit their use to short periods.
ABSTRACT: Traditionally, cranberry has been used for the treatment and prophylaxis of urinary tract infections. Research suggests that its mechanism of action is preventing bacterial adherence to host cell surface membranes. Systematic reviews have concluded that no reliable evidence supports the use of cranberry in the treatment or prophylaxis of urinary tract infections; however, more recent, randomized controlled trials demonstrate evidence of cranberry's utility in urinary tract infection prophylaxis. Supporting studies in humans are lacking for other clinical uses of cranberry. Cranberry is a safe, well-tolerated herbal supplement that does not have significant drug interactions.
ABSTRACT: Over-the-counter dietary supplements to treat obesity appeal to many patients who desire a 'magic bullet' for weight loss. Asking overweight patients about their use of weight-loss supplements and understanding the evidence for the efficacy, safety, and quality of these supplements are critical when counseling patients regarding weight loss. A schema for whether physicians should recommend, caution, or discourage use of a particular weight-loss supplement is presented in this article. More than 50 individual dietary supplements and more than 125 commercial combination products are available for weight loss. Currently, no weight-loss supplements meet criteria for recommended use. Although evidence of modest weight loss secondary to ephedra-caffeine ingestion exists, potentially serious adverse effects have led the U.S. Food and Drug Administration to ban the sale of these products. Chromium is a popular weight-loss supplement, but its efficacy and long-term safety are uncertain. Guar gum and chitosan appear to be ineffective; therefore, use of these products should be discouraged. Because of insufficient or conflicting evidence regarding the efficacy of conjugated linoleic acid, ginseng, glucomannan, green tea, hydroxycitric acid, L-carnitine, psyllium, pyruvate, and St. John's wort in weight loss, physicians should caution patients about the use of these supplements and closely monitor those who choose to use these products.
A Practical Guide to Infant Oral Health - Article
ABSTRACT: Early childhood caries is the most common chronic disease in young children and may develop as soon as teeth erupt. Bacteria, predominately mutans streptococci, metabolize simple sugars to produce acid that demineralizes teeth, resulting in cavities. Physicians should examine children's teeth for defects and cavities at every well-child visit. Any child with significant risk factors for caries (e.g., inadequate home dental care and poor oral hygiene, a mother with a high number of cavities, a high sugar intake, enamel defects, premature birth, special health care needs, low socioeconomic status) should be referred to a dentist by 12 months of age. Promoting appropriate use of topical and systemic fluoride and providing early oral hygiene instruction can help reduce caries in young patients, as can regularly counseling parents to limit their child's consumption of sugar.
Nutrition in Toddlers - Article
ABSTRACT: Toddlers make a transition from dependent milk-fed infancy to independent feeding and a typical omnivorous diet. This stage is an important time for physicians to monitor growth using growth charts and body mass index and to make recommendations for healthy eating. Fat and cholesterol restriction should be avoided in children younger than two years. After two years of age, fat should account for 30 percent of total daily calories, with an emphasis on polyunsaturated fats. Toddlers should consume milk or other dairy products two or three times daily, and sweetened beverages should be limited to 4 to 6 ounces of 100 percent juice daily. Vitamin D, calcium, and iron should be supplemented in select toddlers, but the routine use of multivitamins is unnecessary. Food from two of the four food groups should be offered for snacks, and meals should be made up of three of the four groups. Parental modeling is important in developing good dietary habits. No evidence exists that early childhood obesity leads to adult obesity, but physicians should monitor body mass index and make recommendations for healthy eating. The fear of obesity must be carefully balanced with the potential for undernutrition in toddlers.
ABSTRACT: Use of complementary and alternative medicine has increased over the past decade. A variety of studies have suggested that this use is greater in persons with symptoms or diagnoses of anxiety and depression. Data support the effectiveness of some popular herbal remedies and dietary supplements; in some of these products, particularly kava, the potential for benefit seems greater than that for harm with short-term use in patients with mild to moderate anxiety. Inositol has been found to have modest effects in patients with panic disorder or obsessive-compulsive disorder. Physicians should not encourage the use of St. John's wort, valerian, Sympathyl, or passionflower for the treatment of anxiety based on small or inconsistent effects in small studies. Although the evidence varies depending on the supplement and the anxiety disorder, physicians can collaborate with patients in developing dietary supplement strategies that minimize risks and maximize benefits.
Dietary Supplements for Osteoarthritis - Article
ABSTRACT: A large number of dietary supplements are promoted to patients with osteoarthritis and as many as one third of those patients have used a supplement to treat their condition. Glucosamine-containing supplements are among the most commonly used products for osteoarthritis. Although the evidence is not entirely consistent, most research suggests that glucosamine sulfate can improve symptoms of pain related to osteoarthritis, as well as slow disease progression in patients with osteoarthritis of the knee. Chondroitin sulfate also appears to reduce osteoarthritis symptoms and is often combined with glucosamine, but there is no reliable evidence that the combination is more effective than either agent alone. S-adenosylmethionine may reduce pain but high costs and product quality issues limit its use. Several other supplements are promoted for treating osteoarthritis, such as methylsulfonylmethane, Harpagophytum procumbens (devil's claw), Curcuma longa (turmeric), and Zingiber officinale (ginger), but there is insufficient reliable evidence regarding long-term safety or effectiveness.
ABSTRACT: Herbs, vitamins, and other dietary supplements may augment or antagonize the actions of prescription and nonprescription drugs. St. John's wort is the supplement that has the most documented interactions with drugs. As with many drug-drug interactions, the information for many dietary supplements is deficient and sometimes supported only by case reports. Deleterious effects are most pronounced with anticoagulants, cardiovascular medications, oral hypoglycemics, and antiretrovirals. Case reports have shown a reduction in International Normalized Ratio in patients taking St. John's wort and warfarin. Other studies have shown reduced levels of verapamil, statins, digoxin, and antiretrovirals in patients taking St. John's wort. Physicians should routinely ask patients about their use of dietary supplements when starting or stopping a prescription drug, or if unexpected reactions occur.
Supplements and Sports - Article
ABSTRACT: Use of performance-enhancing supplements occurs at all levels of sports, from professional athletes to junior high school students. Although some supplements do enhance athletic performance, many have no proven benefits and have serious adverse effects. Anabolic steroids and ephedrine have life-threatening adverse effects and are prohibited by the International Olympic Committee and the National Collegiate Athletic Association for use in competition. Blood transfusions, androstenedione, and dehydroepiandrosterone are also prohibited in competition. Caffeine, creatine, and sodium bicarbonate have been shown to enhance performance in certain contexts and have few adverse effects. No performance benefit has been shown with amino acids, beta-hydroxy-beta-methylbutyrate, chromium, human growth hormone, and iron. Carbohydrate-electrolyte beverages have no serious adverse effects and can aid performance when used for fluid replacement. Given the widespread use of performance-enhancing supplements, physicians should be prepared to counsel athletes of all ages about their effectiveness, safety, and legality.