תוספי מזון

תוספי תזונה תוספי מזון, על אף היותם מוצרים שנראים תמימים להפליא, יכולים להסב לא מעט נזק כאשר צורכים אותם לא נכון. 10 טיפים שיעזרו לכם לצרוך את התוספות בחכמה ד''ר אלכס רויטמן 4/12/2006 9:46 1. גוון את מזונותיך בחר מגוון מזונות. ודא שהנך אוכל מכל סוגי המזונות: פחמימות, חלבונים ושומנים תוך הקפדה על כמות קלוריות סבירה. חשוב לצרוך מגוון ירקות ופירות מדי יום. תוספת ויטמינים ותוספי תזונה יעזרו למנוע חסרים אך אינם באים במקום המזון. 2. שאל את הרופא שאל את הרופא שלך איזה תוספים כדאי לקחת. על סמך היכרותו איתך ועם מצב בריאותך ובדיקת הרגלי התזונה שלך הוא האדם הכי מתאים להתייעץ איתו. אל תסמוך על דיילים או אנשי מכירות שהידע שלהם לא מספיק. 3. דע שיש שילובים מסוכנים אם הנך לוקח תרופות יחד עם תוספי תזונה היה מודע לאפשרות של השפעות גומלין ביניהם ותמיד התייעץ עם הרופא המטפל בך. לדוגמא: קומדין (תרופה לדילול דם), אספירין (נמכר חופשי מעבר לדלפק), ויטמין E ג‘ינקו בילובה (תוסף תזונה) ואומגה 3 (תוסף תזונה) כולם מדללים את הדם. שילוב ביניהם עלול לגרום לדילול יתר ולדימום. אין זה אומר שאסור לשלב ביניהם אך חשוב להיות ערני לתופעות ותמיד להתייעץ עם הרופא המטפל בך. 4. זהירות לפני ניתוח אם הנך עומד לעבור ניתוח ונוטל את אחד המרכיבים הנ"ל או כל תוסף תזונה אחר, דווח על כך לרופא בכדי שינחה אותך אם להפסיק לקחת אותם, מתי ולכמה זמן. 5. תוספי תזונה אינם תרופות זכור שתוספי תזונה כשמם כן הם, תוספים לתזונה. הם אינם תרופות למרות שאריזתם בכדורים או כמוסות עלול להטעות. במקרים מסוימים הרופא עשוי לרשום לך ויטמין או תוסף תזונה על סמך בדיקה ואבחון של בעיה רפואית ספציפית. 6. תופעות לוואי גם לתוספי תזונה יש תופעות לוואי. אם מופיעות אצלך תופעות כלשהן וודא שאינן קשורות לתוספים. 7. נוסחאות סודיות ותכונות פלא הזהר ממוצרים שלא מצוינת תכולתם או שמייחסים להם תכונות מופלאות שאינן מבוססות על הוכחות מדעיות. גם כשמציינים יעילות במחקרים יש לוודא שהמחקרים הם בעלי ערך מדעי. הרופא או הדיאטנית שלך יכולים לבדוק אם המחקר בעל ערך מדעי. 8. ממי לקנות הקפד לרכוש ויטמינים מחברות ידועות, ממקור אמין שמייצר לפי תקנים ובקרת איכות קפדנית. 9. יותר זה לא תמיד יותר טוב. תוספי תזונה יכולים לעזור לספק את הכמות היומית הנחוצה אך יש לשים לב לא לצרוך כמויות גדולות מדי של ויטמינים ממקורות שונים. יש אנשים שחושבים שלקחת הרבה מדבר טוב ישפר את בריאותם. הדבר בלט במיוחד בצריכת כמויות גדולות של ויטמין E שמצטבר בגוף היות והוא מסיס בשומן. סקירת מחקרים לגבי נטילת ויטמין E בחולים כרוניים הראתה שצריכה מעל 400 יחידות ליום לא רק שלא גרמה לשיפור אלא גרמה להשפעה הפוכה ודווקא לעליה בתמותה. 10. אל תאבחן בעצמך מחלות. אם הנך חושב שאתה סובל מבעית בריאות כלשהי אל תנסה לאבחן ולטפל בה בעצמך. תמיד התייעץ עם הרופא שלך, יכולת האבחון שלו יותר טובה משלך. ספר לו על הבעיה, התופעות וענה על שאלותיו. יחד תגיעו להחלטות על הטיפול האופטימאלי.

מינון גבוה מיותר ומזיק. גלולות אינן תחליף לתזונה בריאה. Experts cut through the hype about the health benefits of vitamin supplements. WebMD Feature Reviewed By Louise Chang, MD There are enough myths around vitamins to make an ancient Greek blush, AND it's easy to see why. We all know that vitamins AND minerals are essential to good health -- it says so right there on the cereal box. AND we live in the more-is-better era of Hummers, Big Gulps, AND McMansions. Which raises the obvious question: if taking 100% of the Recommended Dietary Allowance (RDA) of, say, vitamin C is good enough to keep us going through the day, then why shouldn't taking 1,000% be enough to melt our fat, cure our blues, AND let us leap tall buildings in a single bound? Meanwhile, the $19 billion-a-year dietary supplement industry continually reminds us that we can get our vitamins from a pill. Which invites yet another question: Why should we bother choking down bushels of brussels sprouts when we could get the same effect by sprinkling supplement shavings over our Boston cream pie? If life were only that easy. The broad consensus from nutrition experts -- OR at least the ones who aren't buying Hummers with the proceeds from supplement sales -- is that while vitamins are indeed essential, big doses are usually pointless AND can even be harmful. AND no pill is likely to ever adequately substitute for a healthy diet. Why They Matter Vitamins AND minerals are substances your body needs for normal growth AND functioning. Some facilitate crucial chemical reactions, while others act as building blocks for the body. Nutritionists call vitamins AND minerals "micronutrients" to distinguish them from the macronutrients such as proteins, carbohydrates, AND fats that make up the bulk of our food. While micronutrients are vital for the proper processing of macronutrients, they're needed in smaller quantities. Think of it this way: If macronutrients are the gas in your engine, then micronutrients are like the motor oil, coolant, AND battery fluid. Micronutrient deficiency can lead to acute diseases with exotic names like scurvy, pellagra, AND beriberi. Deficiency diseases were common in the U.S. until the 1940s, when the FDA-mandated fortification of common foods like bread AND milk. These diseases are still common in many poorer countries. Maintaining a Healthy Diet It's easy to get enough micronutrients from your food if you maintain a healthy diet, Audrey Cross, PhD, associate clinical professor of nutrition at Columbia's School of Public Health, tells WebMD. But most people fail that test; they'll eat two OR three servings of fruits AND veggies per day rather than the recommended five. That's why Cross (and many other nutritionists) suggest a multivitamin as a sort of nutritional safety net for many of their patients. But it's just a safety net. So-called "whole foods" like veggies AND whole grains contain fiber AND a host of other important nutrients that can't be adequately delivered through pills. In fact, scientists are still finding new "trace elements" in whole foods that may someday be labeled essential to health -- but aren't found in any pill. "There are literally thousands of these compounds, AND we're just scratching the surface on knowing what their role is," says David Grotto, a registered dietitian AND spokesman for the American Dietetic Association. "We're sending the wrong message if people believe they've got everything under control AND if they're taking vitamins while eating a horrible diet." Choosing a Supplement It's easy to become overwhelmed when looking at the dietary supplement shelves of a health food store OR even your local supermarket. While many of the health claims are unproven OR downright bogus, some supplements may be useful for some groups. Major multivitamin makers typically produce different varieties for men, women, children AND older folks. Picking a pill that fits your group makes sense, says dietitian Grotto, as the optimal level of various nutrients varies by age AND sex. For example, premenopausal women need more iron than children OR the elderly, he says. But the elderly have a harder time obtaining adequate amounts of vitamin B-12 from natural sources, so the need for supplementation may increase with age, says Lynn Bailey, a University of Florida nutritionist who teaches courses on vitamins. Folate, OR folic acid, is key to preventing birth defects (such as spina bifida), Bailey says. Bailey says all women of childbearing age should ensure they get 100% of the RDA of folic acid through fortified food OR a multivitamin. Calcium AND Vitamin D Calcium supplements are also important for certain age groups, Bailey says. The Institute of Medicine, part of the National Academy of Sciences, recommends that adolescents get 1,300 milligrams of calcium a day. One cup of milk OR calcium-fortified orange juice contains about 300 milligrams of calcium. Other sources of calcium include cheese, tofu, yogurt, vegetables, AND beans. A typical calcium supplement may contain 500 milligrams OR 600 milligrams of calcium. Bailey gives her 15-year-old son a daily calcium supplement at dinnertime. People over 50 should get 1,200 milligrams a day of calcium to ward off osteoporosis (thinning of the bones), Bailey says. Federal dietary guidelines recommend that the elderly, the homebound, AND people with dark skin boost their vitamin D intake with both fortified foods AND supplements to reduce the risk of bone loss. Vitamin D helps with absorption of calcium; often calcium supplements will also contain vitamin D. (The full federal guidelines, updated in 2005, are available at www.health.gov/dietaryguidelines.) Special groups such as smokers, pregnant women, OR people recovering from traumatic injury may need additional supplements, Cross says. Decisions to take supplements beyond a multivitamin are best made with your doctor OR registered dietitian, she says. The evidence is strong that a healthy diet can ward off chronic diseases like cancer AND heart disease. What's less clear is if big intakes of particular micronutrients can boost that preventive effect further. There is promising evidence that the mineral selenium could prevent a variety of cancers, says Alan Kristal, DrPh, associate chief of cancer prevention at the Fred Hutchinson Cancer Research Center in Seattle. But beyond selenium, the data aren't promising, Kristal says. For example, there's no solid evidence that taking large doses of antioxidants like vitamins B OR C have any beneficial effect. Controversial Health Claims As you seek the proper multivitamin OR dietary supplement, it's best to keep your guard up. The supplement industry is relatively unregulated, AND you can injure OR even kill yourself with "natural" products bought at your neighborhood supplement store. Many health claims attached to multivitamin formulations are doubtful, but harmless. Some men's multivitamins contain extra lycopene, a substance once thought to prevent prostate cancer. But Kristal, the cancer specialist, says support for that claim is waning. "If indeed lycopene did anything, [supplements] don't have enough to make a difference," he says. Multivitamins aimed at women are often spiked with green tea OR ginseng extract; the effect of these on weight control is yet unproven. More dangerous are recommendations of vitamin megadoses to treat obesity, depression, carpal tunnel syndrome OR other problems. At best, megadoses are a distraction from real treatments for these problems, experts say. At worst, they can cause injury OR death. So-called fat-soluble vitamins -- that is, vitamins A, D, E, AND K -- accumulate in the body, making overdosing a real threat. Vitamin overdoses have been associated with liver problems, weakened bones, cancers, AND premature mortality. Until recently, water-soluble vitamins such as B AND C were considered nontoxic, even at high doses. But now evidence is emerging that B-6 megadoses can cause serious nerve damage, Bailey tells WebMD. Despite the warnings, the quest for a magic pill plunges ahead. Cross chuckles when patients show her weight loss supplements that claim wondrous effects "when taken in combination with a sensible diet AND exercise." Her response: Wouldn't a sensible diet AND exercise do the trick even without the supplement? Published Feb. 20, 2006. -------------------------------------------------------------------------------- SOURCES: Harvard School of Public Health web site: "Vitamins." Mayo Clinic web site: "Vitamin AND mineral supplements: Use with care." U.S. Department of Health AND Human Services: "Dietary Guidelines for Americans 2005." Lynn B. Bailey, professor of human nutrition, food science AND human nutrition, University of Florida, Gainesville. Audrey Cross, PhD, associate clinical professor of nutrition, Mailman School of Public Health, Columbia University. David Grotto, registered dietitian; spokesman, American Dietetic Association. Alan Kristal, DrPh, professor of epidemiology, University of Washington; associate director of cancer prevention, Fred Hutchinson Cancer Research Center. -------------------------------------------------------------------------------- © 2006 WebMD Inc. All rights reserved.

אם היית קורא את הספר של ד"ר ברנר וגם מבין מה שאתה קורא, היית מרגיש מטופש אפילו לשלוח את זה. מחקרים רבים הראו את התועלת של מינונים גבוהים של ויטמינים נגד סרטן ומגוון מחלות אחרות. אם זה כואב לך זו בעיה אך ורק שלך.

Am J Clin Nutr. 2006 Feb;83(2):191-201. The acute AND chronic toxic effects of vitamin A. The acute AND chronic effects of vitamin A toxicity are well documented in the literature. Emerging evidence suggests that subtoxicity without clinical signs of toxicity may be a growing concern, because intake from preformed sources of vitamin A often exceeds the recommended dietary allowances (RDA) for adults, especially in developed countries. Osteoporosis AND hip fracture are associated with preformed vitamin A intakes that are only twice the current RDA. Assessing vitamin A status in persons with subtoxicity OR toxicity is complicated because serum retinol concentrations are nonsensitive indicators in this range of liver vitamin A reserves. The metabolism in well-nourished persons of preformed vitamin A, provided by either liver OR supplements, has been studied by several research groups. To control vitamin A deficiency, large therapeutic doses are administered in developing countries to women AND children, who often are undernourished. Nevertheless, little attention has been given to the short-term kinetics (ie, after absorption but before storage) of a large dose of vitamin A OR to the short- AND long-term effects of such a dose given to lactating women on serum AND breast-milk concentrations of retinol AND its metabolites. Moreover, appropriate dosing regimens have not been systematically evaluated to ascertain the quantitative improvement in vitamin A status of the women AND children who receive these supplements. The known acute AND chronic effects of vitamin A toxicity have been reported previously. However, further research is needed to ascertain the areas of the world in which subclinical toxicity exists AND to evaluate its effects on overall health AND well-being. **************************************** Nippon Rinsho. 2006 Sep;64(9):1707-11. [Nutrition-related bone disease] Bone disorders clearly related to nutrition are osteomalacia AND osteoporosis. Osteomalacia is caused by a deficiency of vitamin D OR a disturbance of its metabolism. Dietary deficiency of phosphate OR excess of aluminum OR cadmium will also cause osteomalacia. Osteoporosis is associated with low intake of calcium AND other nutrients. Dietary copper deficiency might stimulate bone metabolism AND increase in hip fractures. Excess vitamin A intake was also associated with lower bone mineral density AND higher risk of hip fractures. Excess vitamin D sometimes causes mental simplicity, congenital heart disease AND calcification of soft tissue. Therefore not only diet but also drugs AND supplements of nutrients should be carefully observed in older women ************************************* Ned Tijdschr Geneeskd. 2003 Apr 19;147(16):752-6. A balanced diet based on the Guidelines of the Netherlands Nutrition Centre provides a suitable basis for the maintenance of good health. However, there are a number of situations where supplementation with vitamins is clearly indicated. These include infants (vitamin A, D AND K), young children, AND pregnant AND lactating women (vitamin D), future expectant mothers (folic acid) AND the elderly (vitamin D). If doubts exist about a sufficient vitamin intake via the regular diet, a daily supplement supplying all vitamins at the level of the recommended daily allowance (RDA) is considered to be a responsible AND safe choice. Epidemiological research indicates that the incidence of certain diseases is lower if the intake of vitamins is significantly higher than the RDA. However to date, targeted intervention studies have provided little unequivocal evidence to support this argument. For certain vitamins (A, D, folic acid, B6, nicotinic acid AND beta-carotene) excessive intakes are associated with a health risk OR clear toxicity. In the case of vitamin B6, nicotinic acid, folic acid AND beta-carotene this risk is mainly limited to the use of high-dose supplements. ******************************** 1: Liver Transpl. 2006 Dec;12(12):1892-5. Acute liver failure induced by green tea extracts: Case report AND review of the literature. In industrialized countries, over-the-counter dietary supplements have become popular in preventing AND treating an expanding list of medical conditions. Although most commercially available supplements have not been rigorously tested for safety AND efficacy, they have found an enlarging market because they are considered natural. Oral supplements containing green tea extract have been marketed as effective for weight loss AND to prevent AND cure some solid tumors. Although there is little scientific evidence of the effectiveness of green tea extracts to improve the quality of health of regular consumers, there is an increasing body of medical literature supporting the hypothesis that they can cause serious side effects. Our experience adds to previous reports of acute liver toxicity observed in individuals consuming supplements containing green tea extract. We highlight the importance of obtaining a detailed history of dietary supplement consumption when evaluating a patient presenting with acute liver dysfunction.