Are Dietary Supplements Useful and How to Choose Between Them?
The use of nutritional supplements among athletes is widespread. Nearly nine out of ten Canadian athletes take supplements. Sports drinks, multivitamins and protein powders are among the most popular. Athletes that use supplements usually want to prevent nutritional deficiencies, increase their energy level, recover better after exercise, optimize their body composition or increase their muscle strength. But is it really useful to take supplements and if so, which ones should you choose?
In which cases is taking supplements justified?
Scientific evidence supports the use of certain sports products (drinks, bars, gels, protein powders, meal replacements, electrolytes) to meet athletes’ nutritional needs in situations when it is not practical to consume real foods, for example during a competition or after training when it is not possible to eat quickly. Taking medical supplements (multi-vitamins, iron, calcium, vitamin D and probiotics) may also be warranted for treating nutritional deficiencies or diagnosed health problems. Finally, the use of a few supplements is supported by enough scientific evidence to justify their use for high performance athletes. Those supplements are: caffeine, beta-alanine, bicarbonate, beetroot juice and creatine. Taking these supplements is only relevant when the other determinants of performance (diet, training, recovery, etc.) are already optimal. All other types of supplements are not supported by enough scientific studies to be recommended or are banned by the World Anti-Doping Agency.
Can supplements be dangerous?
A supplement designated as a ‘’natural’’ product inspires trust by suggesting that it is automatically safe. However, natural health products can pose a health risk. For example, taking a mega dose of a certain vitamin can inhibit the absorption of other vitamins. Supplements may also contain ingredients that may interfere with prescribed medication. Some products contain a lot of caffeine, which can increase blood pressure and cause palpitations, tremors, irritability, insomnia and even death. Finally, products may have been inadvertently contaminated with prohibited and dangerous substances during the manufacturing process, or even further, manufacturers may deliberately add substances, such as steroids and stimulants, while failing to mention it on the label.
Let’s start with a balanced and varied diet!
You should know that a varied and balanced diet can meet the nutritional needs of the majority of athletes. Most of the active substances contained in supplements such as vitamins, minerals, antioxidants, proteins and branched-chain amino acids (BCAA), to name a few, can also be found in food. However, in addition to providing the active ingredient in question, for example vitamin C, food contains a multitude of other nutrients such as fiber and other vitamins, that act synergistically to promote optimal health and optimize performance.
The sale of supplements generates billions of dollars for an industry that has an interest in making its products attractive. Don’t fall into the trap! Never rely on company ads or slogans on products’ packaging to judge their safety and effectiveness. Keep in mind that in the majority of cases, you can achieve the desired results by changing your workout and diet. This is a cheaper, safer and often more effective way than taking supplements. Dieticians and kinesiologists are health professionals dedicated to helping you. Don’t hesitate to consult with them and their expertise!
How to choose a supplement brand?
In cases where taking a supplement is warranted, it may be difficult to select a product from the many choices available. Since 2004, supplements sold in Canada must all have a Natural Product Number (NPN). This designation indicates to the user that the formulation, labeling, and directions for use of the product have been reviewed and approved by Health Canada. On the other hand, this is not the case for supplements sold on the Internet that come from other countries. To avoid consuming contaminated products, it is recommended that you choose a product that contains a logo (NSF Certified for Sport, Good Manufacturing Practice (GMP) or Informed Choice), meaning that it has been subjected to rigorous evaluation criteria that allows the detection of any banned or dangerous substance. It should be noted that even if the product contains an NPN or a logo, this does not guarantee its effectiveness at all. Finally, before using any supplement, be aware that athletes are responsible for any banned substance they ingest, hence the importance of using extra caution.
- Extenso (2016): «Suppléments alimentaires et sport : les dangers cachés.» http://www.extenso.org/article/supplements-alimentaires-et-sport-les-dangers-caches/, 27 octobre.
- Burke L. et Deakin V. (2015): Clinical Sports Nutrition, 5th Edition. McGraw-Hill Education, 828 pages.