Intake of nutritional supplements among people exercising in gyms and influencing factors.

OBJECTIVE To assess supplement intake in people who exercise regularly in gyms in the city of Belo Horizonte, Brazil, and discuss the influencing factors on its ingestion. METHODS A total of 1102 enrolled subjects who exercised in 50 gyms throughout the city were part of this cross-sectional study. Men and women were recruited and all subjects were at least 18 y old. Participants were asked to complete written questionnaires about their use of supplements. Data were collected over a period of 4 mo. Descriptive statistics and chi-square tests were performed. RESULTS The intake of nutritional supplements was reported by 36.8% of participants. The highest intake was in men (44.6%). Five products were consumed almost daily: those rich in proteins and amino acids (58%), isotonic drinks (32%), those rich in carbohydrates (23%), natural/phytotherapeutic (20%), and multivitamin/mineral supplements (19%). Most people (55%) reported using nutritional supplements without any specialized professional guidance and based primarily on self-prescription. Individuals younger than 30 y, mainly men (odds ratio 3.28, 95% confidence interval 2.06-5.20, P < 0.01), took supplements rich in proteins (odds ratio 2.73, 95% confidence interval 1.26-5.94, P < 0.05). In contrast, older participants reported taking supplements rich in multivitamin/minerals and natural/phytotherapeutic agents (odds ratio 5.52, 95% confidence interval 2.76-11.06, P < 0.01). CONCLUSION Our results show that supplement intake in people exercising in gyms is high and is usually self-prescribed. We emphasize that the use of dietary supplements must be always done under the supervision of a specialist (physician or nutritionist).