Nutritional Supplements & Exercise

Should I be taking supplements to enhance performance or weight loss? This question has been asked by many athletes, avid exercisers and dieters for many years. What is the truth about supplements? Supplement companies and advertisers in the commercial fitness industry would have you believe that supplements, herbs and fad diets are essential to you achieving your goals. But over the last 20 years research has clearly documented the beneficial effects of good nutrition on exercise performance and weight management (gain or loss). When or why should I take supplements then? There are only 2 scientifically valid reasons for using dietary supplements. The first is to optimize a body function. This would only be required if the delivery of the nutrient in question is low. This could be because of poor food selection, inadequate food intake, or a metabolic disorder or other problem that disrupts the absorption of a substrate. The second is when there is a diseased condition where diet cannot be modified to provide adequate amounts of a vitamin. What Do the Professionals Say? It is the joint position of the American Dietetic Association, Dieticians of Canada and the American College of Sports Medicine that physical activity, athletic performance and recovery from exercise are enhanced by optimal nutrition. In addition, these organizations conclude that this can be achieved through appropriate selection of foods and fluids, timing of intake, and supplement choices where needed. Some of their key points are as follows: During times of high physical activity adequate energy is needed to prevent loss of muscle mass, menstrual dysfunction, loss or failure to gain bone density and increased risk of fatigue, injury, and illness. (So a balanced diet is key!) Recommended protein intakes can generally be met through diet alone without the use of protein or amino acid supplements, if adequate energy is eaten to maintain body weight. There is no benefit of eating a diet with less than 15% energy from fat as it provides energy, fat-soluble vitamins and essential fatty acids. Drink plenty of water before, during and after exercise to replace fluid loss due to sweating and other mechanisms. Eat meals high in carbohydrates, low in fat, and moderate in protein before and after exercise that are well tolerated by the participant. In general no vitamin and mineral supplements should be required if the exerciser is consuming adequate energy from a wide variety of foods to maintain a healthy body weight. No single-nutrient supplements should be used without a specific medical or nutritional reason (i.e. iron supplements to reverse iron-deficiency anemia). Vegetarian exercisers may be at risk for low energy, protein and micronutrient intakes. Consultation with a Registered Dietician will help avoid these problems. If I am considering dietary supplementation what should I do? You should always follow the advice of your Registered Dietician or health care provider and notify them of any type of herbs or supplement preparations that you are taking before starting any exercise program. The supplement companies often project exaggerated or outrageous claims regarding their products, most of which are not supported by any scientific literature. You should always be aware of the following when choosing a recommended vitamin or mineral supplement: The serving of a nutrient or compound will be absorbed quite differently depending on the way and form it is delivered. For example, iron is absorbed differently from a serving of liver or vegetable serving versus in capsule form. Further, whether the capsule is taken with water, tea or orange juice can have an impact as well. (Vitamin C enhances iron absorption by the way!). The purity of the compound or nutrient may not be pure. If a one-gram capsule of a compound is not pure at least two problems arise. One, you are not getting the proposed amount of the nutrient and two, there may be an unknown compound that you are receiving that may cause harm. Only pharmaceutical-grade compounds are regulated. Compounds that are not drugs do not have the same stringent regulations that provide the same safety and quality standards. Recent research has shown that supplements vary widely in purity from 100% to undetectable concentrations from bottle to bottle, and with some products within the same container! (Buyer Beware!) Conclusion The latest research from the highest governing bodies of sports and nutrition mutually agree that supplementation for sport or weight loss is not superior to optimal nutrition practices, and could also be potentially harmful. To gain the results you desire the best decision is to consult Canada's Food Guide or your local health care provider, registered dietician or family physician. For more excellent nutrition and training info keep browsing the SHAPE website for top notch advice! SHAPE POLICY ON DIETARY SUPPLEMENTS Shape is in agreement with the latest research and joint position of the American College of Sports Medicine and the Dieticians of Canada and does not support or endorse the use of commercial fitness supplements and ergogenic aids unless prescribed by a physician or approved by the Clinic Director or Registered Dietitian on site for the following reasons: In general, no vitamin and mineral supplements should be required if the exerciser is consuming adequate energy from a wide variety of foods to maintain a healthy body weight. No single-nutrient supplements should be used without a specific medical or nutritional reason (i.e. iron supplements to reverse iron-deficiency anemia). Vegetarian exercisers may be at risk for low energy, protein and micronutrient intakes. Consultation with a Registered Dietician will help avoid these problems.