Author: Valeria Laza
Affiliation: Hygiene, Department of Community Medicine, “Iuliu Haţieganu” University of Medicine and Pharmacy Cluj-Napoca, Romania
Abstract
Proteins in the athlete’s diet are used for muscle growth and repair; cell regulation; immune and neurological functions; nutrient transport and structural support. Protein needs depend on many variables: energy intake, exercise type (1.2 to 1.5 g/ kg/day for endurance, and 1.2 to 1.7 g/kg/day for strength athletes), duration and intensity of exercise, and the training phase (novice vs. trained). The best sources of proteins preferred by athletes are whey, egg white and soy derivative products. Soy has many virtues, as well as a long record of unhealthy compounds (also called antinutrients): endocrine disruptors, saponins, enzyme inhibitors, goitrogens, phytates, pesticides, etc. Athletes prefer their convenience and ease of use, so they consume protein supplements such as protein concentrates and isolates, which are highly refined and processed forms of soy.
Beside the negative effects of soy antinutrients, high ingestion of soy protein supplements has detrimental results: dehydration and calcium loss (due to high protein intake); presence of toxic substances (aluminum, nitrites, lysinoalanine) in processed soy-based products.
During the last 3-4 decades, soy has become a very controversial and complicated topic. For every study showing the nutritional value of soy, another one claims the detrimental effects on health, so, reviewing the data on soy is very confusing. Moreover, in order to clarify the truth, many other confounding dietary factors should be taken into consideration.
For soy to be a healthy food, it is recommended to be organic, used in a properly fermented form, occasionally, and in moderate amounts.
Keywords: athletes, soy, soy-based products, proteins, antinutrients