Dietary supplement use by adolescents.

OBJECTIVES To review the use, benefits and adverse effects of the main dietary supplements consumed by adolescents. SOURCES The literature review was performed using MEDLINE and LILACS databases (1997-2008). We analyzed 377 articles, and 52 of them were selected as references. SUMMARY OF THE FINDINGS Consumption of dietary supplements is widely spread among adolescents. This habit has often been detected in pediatric and adolescent medicine clinics. Most of the time, the use of supplements is motivated by the search of the ideal body. Other reasons for this practice are: attempt to compensate for an inadequate diet, increase immunity, prevent diseases, improve athletic performance and overcome their own athletic limits. The dietary supplements most frequently used and for which there is little evidence of beneficial effects in healthy adolescents are: proteins, amino acids, beta-hydroxy-beta-methylbutyrate, microelements, carnitine, creatine, vitamins, caffeine, and bicarbonate. This dietary supplementation may be beneficial for competitive athletes who do not have a balanced diet after a specific dietary deficiency has been detected. CONCLUSION The unrestrained consumption of dietary supplements should be avoided, since, besides the lack of evidence that such practice will lead to improvement of performance, it exposes adolescents to several adverse effects. Balanced nutrition, with intake of essential energy and nutrients is usually enough to achieve good athletic performance. The use of dietary supplements must be allowed only for selected cases in which specific nutritional deficiencies are identified.