The practice of physical exercises has been growing strongly in the last decade, parallel to this practice is the growth of supplement consumption, supplement by definition is a substance to meet some possible nutritional deficiency, and can be marketed also for ergogenic purposes both for aesthetic improvement or Yield.

In Brazil the best-selling supplements are those based on protein, especially whey protein, whey proteins, also called whey protein have a globular structure containing some disulfide bridges. They have high biological value, high content of essential amino acids and branched chain, high calcium content and bioactive peptides. Its effects result in an increase in plasma insulin concentration favoring the uptake of amino acids into the muscle cell.

Whey protein intake is positive at some points, such as those reported in studies such as Frid et al. (2005), which show that consumption of whey protein for a mean of 12 weeks reduced plasma levels of postprandial triglycerides in the group Takasaki et al. (2004), in mice, showed that whey protein supplementation caused a reduction in serum glucose levels in the animals.

The biggest problems with the consumption of supplements are when the consumer does not have full information about the product he or she is buying, which consumption is not usually encouraged by nutritionists but by: coaches, friends or media.

The media have a strong influence on people, encouraging them or making them believe that there is a need for daily use of supplements to achieve their goals. As an example of this it can be mentioned that in 2001 the food supplement industry invested globally $ 46 billion in advertising as a means of persuading potential consumers to purchase their products, which consumption is often unnecessary if there is a balanced diet and follow-up of a nutritionist. According to Hernandez and Nahas (2009), the additional consumption of protein supplements above the daily needs of an athlete, which can be contemplated by a healthy diet, does not determine additional muscle mass gain or performance increase.

Other problems found in protein-based supplements are the non-delivery of the protein content reported on the label, replacement of whey protein by cheaper proteins and variation of protein and carbohydrate amounts when dealing with different brands.

The present study aimed to quantitatively evaluate the chemical composition of carbohydrates and proteins in 35 samples purchased in the retail trade of the city of Recife, evaluating the adequacy of the composition of these nutrients in relation to the label and the current legislation.

This is a cross-sectional and analytical study carried out during the months of November 2017 until October 2018, in which the labels of protein supplements of whey protein concentrate sold in the city of Recife - PE were selected. most sold, taking into account information passed by store owners.

The establishments were chosen randomly, in different districts of the city. Before the beginning of the study, the consent of the managers of the establishments was requested in order to initiate the evaluation of the labels of the products of interest of the study sold there.

It was observed that the marks were repeated among the stores observed. Thus, data from the labels of 35 brands of different protein supplements were collected.

In this study, 35 labels of whey protein concentrate protein supplements were evaluated, including 21 national brands and 14 imported brands.

As far as labeling is concerned, of the 35 marks observed, 34 are adequate according to chapter three, article eighth of RDC / ANVISA 18/1013, only mark B is inadequate because it violates item II of this article, since presents more than 15 grams of carbohydrate per serving, that is, the supplement in question has less than 50% of the total energetic value of proteins and 37.5% more carbohydrate than protein per serving. This reality is also included as a misleading advertisement, thus violating section IV, article six, chapter three of Law 8.078 / 90 (Brazilian Code of Protection and Consumer Protection).

One point that is important to note is the change in the concentration of carbohydrates and proteins among brands, sometimes changes found in brands produced in the same country, for example, in the study were observed brands that have 5.2 grams of protein more than the concentration of carbohydrates per serving, while brands that have 20.6 grams of protein more than the carbohydrate concentration per serving were observed.

On the other hand, when the analysis goes further as was done by the national institute of metrology, quality and technology (INMETRO), which analyzed laboratorially 15 whey protein marketed in Brazil, using the methods of kjeldahl, total protein content and methodology of Lane -Eynon, the results are catastrophic, since among the 15 brands observed, only 1 had 100% of conformities, because quantitatively speaking, 2 brands had a reduction of more than 25% of the amount of protein informed on the label and 11 brands had a quantity different from carbohydrates, among them two specific brands had a number greater than 250% more carbohydrates than the one declared on the label. As for quality, 11 brands contained undeclared substances on their labels, mainly caffeine, and 1 contained wheat and soy protein.

After the analysis of the 35 protein supplement labels, irregularities were observed, which are irregularities that harm consumers who buy a product expecting an improvement in yield and / or aesthetics, but sometimes end up failing to obtain the expected results.

Ideally, companies should perform better quality control and use their product labels to truthfully inform the contents of the packaging and not just use them as a marketing vehicle. And that the norms governing the sale and consumption of supplements are more firm and specific as regards the maximum and minimum limits of carbohydrate and protein contents offered.

It is also pointed out that it is essential to indicate the consumption by a nutritionist, both for a case-by-case analysis of the consumption of supplements, and for the correct choice of supplement and the quantity required for each individual.

In Brazil the most sold supplements are those based on protein, mainly whey protein. The consumption of whey protein has positive points, and some negatives, the biggest problems of the consumption of supplements occur when the consumer does not have total clarification on the product that is acquiring. Other problems found in protein-based supplements are the non-delivery of the protein content reported on the label and the replacement of whey protein by cheaper proteins.