ID 418 - Białka serwatkowe

PL: Białka serwatkowe
EN: Whey Protein
Pdf: whey protein

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The food constituent that is the subject of the health claims is whey protein.
Whey protein is a mixture of globular proteins isolated from whey, a by-product obtained during the manufacturing of cheese from cow's milk. Beta-lactoglobulin (approx. 50 %), alpha-lactalbumin (approx 20 %), bovine serum albumin (approx 10 %) and immunoglobulins are the major protein fractions in whey.
Whey can be treated and processed in different ways depending on the type of whey protein end products to be obtained. Main commercial forms are concentrates (29-89 % protein by weight), isolates (about 90 % protein by weight) and hydrolysates (partially pre-digested). Small differences in composition between different whey protein products may exist depending on the manufacturing processes applied. These products generally have a high content of essential amino acids, especially high proportions of available lysine and cysteine.
A claim on protein and growth or maintenance of muscle mass has been assessed by the Panel with a favourable outcome (EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), 2010). In this opinion, the Panel will address whether the consumption of whey protein has any effect on growth or maintenance of muscle mass over and above the well established role of protein on the claimed effect.
The Panel considers that the food constituent, whey protein, which is the subject of the health claims, is sufficiently characterised in relation to the claimed effects.

2.3. Wzrost lub utrzymanie masy mięśniowej (ID 418, 419, 423, 426, 427, 429, 4307)

The claimed effects are “promotes protein synthesis when taken after resistance exercise”, “supports an increase in lean body mass when combined with exercise and a hypercaloric diet”, “muscle mass maintenance in the elderly” and “muscle strength and body composition”. The Panel assumes that the target population is the general population.
In the context of the proposed wording, the Panel assumes that the claimed effect refers to the growth or maintenance of muscle mass. Failure to increase muscle mass during growth and development, and the loss of muscle mass at any age, will reduce muscle strength and power.
The Panel considers that growth or maintenance of muscle mass is a beneficial physiological effect.

3.3. Wzrost lub utrzymanie masy mięśniowej (ID 418, 419, 423, 426, 427, 429, 4307)

The majority of the references provided in relation to this claim either assessed the effects of foods or food constituents other than whey protein (e.g. other protein sources, single amino acids, branched- chain amino acids), did not test the specific effect of whey protein (e.g. whey protein in combination with single amino acids, carbohydrates or other protein sources was used as intervention), did not test a specific effect of whey protein as compared to other protein sources (e.g. carbohydrates were used as control), or reported on health outcomes other than muscle growth or maintenance (e.g. acute protein synthesis, protein turnover, and/or body composition without measures of muscle mass). In addition, some of the references provided reported on intervention studies conducted in cancer patients. However, the evidence provided does not establish that results obtained in cancer patients in relation to the claimed effect can be extrapolated to the target population. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Two human intervention studies compared the effects of isonitrogenous whey protein against casein on surrogate measures of muscle mass (Cribb et al., 2006; Demling and DeSanti, 2000).
In a randomised, double blind, parallel intervention study, Cribb et al. (2006) examined the effects of a whey isolate supplement (n = 6) and of a casein supplement (n = 7) provided in addition to the usual diet on strength and body composition during a 10-week intense resistance training programme in a group of 13 resistance trained subjects. Each supplement provided 1.5 g protein/kg body weight/day. Body composition was assessed by duel-energy x-ray absorptiometry (DXA). Strength assessments consisted of the maximal weight (kg) that could be lifted once (1RM) in three weight training exercises: barbell bench press, squat, and cable pull down. Body fat mass significantly decreased in
the whey protein group (-1.5 0.5 kg) compared to casein (+0.2 0.3 kg, p<0.01), whereas lean body mass significantly increased in the whey isolate group (4.99 ± 0.25 kg, P <0.01) compared to the casein group (0.81 ± 0.43 kg). While a significant increase in strength was observed in both groups (p<0.05), such increase was significantly higher in the whey isolate group in all three exercises (p<0.05) compared to the casein group. The Panel notes that, although a direct measure of muscle mass was not performed in this study, an increase in lean body mass associated with an increase in strength supported an increase in skeletal muscle mass, and that such increases were in response to the consumption of whey protein compared to casein.
Demling and DeSanti (2000) conducted a 12-week randomised controlled intervention study where 38 overweight men were randomised to the following groups: 1) no training and hypocaloric diet (80 % of the predicted energy needs, n = 10), 2) resistance training programme, hypocaloric diet and whey hydrolysate (1.5 g/kg per day, n = 11) and 3) resistance training programme, hypocaloric diet and casein hydrolysate (1.5 g/kg per day, n = 11). Body composition was assessed using skinfold thickness and validated equations. Strength for chest, shoulders and legs was assessed as the maximum effort which could be lifted for 8-10 repetitions for a chest press, shoulder press and leg extension. No significant differences in body weight changes between groups were observed. No changes in body fat or lean body mass were observed for the diet-only group, whereas a significant increase in lean body mass and a significant decrease in body fat were observed in the casein and whey groups compared to the diet-only group. The increase in lean body mass and the decrease in
body fat were significantly greater in the casein group compared to the whey protein group (4 1.4 kg
versus 2 0.7 kg, p < 0.05 and -7.0 +/- 2.1 kg versus - 4.2 +/- 0.9 kg, p < 0.05, respectively). Strength for chest, shoulder and legs significantly increased in both the casein and the whey protein groups compared to the diet-only group, and significantly more in the casein group than in the whey protein group (p < 0.05). The Panel notes that, although a direct measure of muscle mass was not performed in this study, an increase in lean body mass associated with an increase in strength supported an increase in skeletal muscle mass, and that such increases were in response to the consumption of casein compared to whey protein.
One human intervention study investigated the effects of whey protein compared to another isonitrogenous protein source (i.e. soy protein; Candow et al, 2006). A total of 27 subjects (18 female), who were not participating in resistance training, were randomised to receive 0.3 g/kg body weight/day of sucrose plus 1.2 g/kg body weight/day of either whey protein or soy protein for six weeks in the context of a resistance training programme. Body composition was assessed by DXA. Strength assessments consisted of the maximal weight (kg) that could be lifted once (one-repetition maximum, 1RM) in two weight training exercises: barbell bench press and squat. No significant differences between the whey protein and the soy protein groups were observed with respect to either body composition or muscle strength.
In weighing the evidence the Panel took into account that only three small intervention studies in humans were pertinent to the claim, and that these studies reported conflicting results with respect to the effects of whey protein on muscle mass compared to other protein sources (i.e. casein and soy protein).
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein and growth or maintenance of muscle mass over and above the well established role of protein on the claimed effect.

Warunki i możliwe ograniczenia stosowania oświadczenia

20 grams of whey protein after exercise Must meet minimum requirements for use of the claim "source of protein" as per Annex to Regulation 1924/2006.