ID 447 - Aminokwasy rozgałęzione

PL: Aminokwasy rozgałęzione
EN: Branched chain amino acids
Pdf: branched-chain amino acids

Oświadczenie (2)

1. Charakterystyka żywności / składnika

The food constituents that are the subjects of the health claims are proteinogenic branched-chain amino acids (BCAA), which are amino acids having aliphatic side-chains that are non-linear, i.e., leucine, isoleucine and valine. The content of BCAA in foods can be measured by established methods.
Leucine, isoleucine and valine are indispensable amino acids provided by mixed dietary protein intakes from different sources. A claim on protein and growth or maintenance of muscle mass has already been assessed with a favourable outcome (EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA), 2010).
BCAA can also be consumed as food supplements. Different mixtures are available in the market. From the references and conditions of use provided in relation to the health claims considered in this opinion, the Panel assumes that the food constituent under evaluation is BCAA consumed in addition to adequate protein intakes.
The Panel considers that the food constituent, branched chain amino acids, which is the subject of the health claims, is sufficiently characterised.

2.1. Wzrost lub utrzymanie masy mięśniowej (ID 442, 444, 445, 447, 448, 451, 1478)

The claimed effects are “reduces protein breakdown after exercise”, “increases protein synthesis”, “recovery/increased protein synthesis in skeletal muscle during recovery from sustained strength exercise” and “muscle metabolism”. The Panel assumes that the target population is the general population.
In the context of the proposed wordings, the Panel assumes that the claimed effect relates to the growth or maintenance of muscle mass by either decreasing muscle breakdown, increasing muscle
synthesis or both. 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.

2.3. Szybsza regeneracja mięśni po wysiłku fizycznym (ID 447, 448, 684, 1478)

The claimed effects are “muscle metabolism” and “promotes muscle recovery after exercise”. The Panel assumes that the target population is active individuals in the general population.
In the context of the proposed wordings and clarifications provided by Member States, the Panel assumes that the claimed effect refers to recovery from muscle fatigue after the performance of physical exercise.
Fatigue can be defined as the loss of peak force or power output. Therefore, muscle fatigue recovery can be defined as regaining maximal muscle strength or muscle power after strenuous exercise, which has induced muscle fatigue. Regaining muscle strength/power may be beneficial during every day life activities and it is beneficial for athletic performance in disciplines where loss of muscle strength and power reduce performance.
The Panel considers that faster recovery from muscle fatigue after exercise is a beneficial physiological effect.

3.1. Wzrost lub utrzymanie masy mięśniowej (ID 442, 444, 445, 447, 448, 451, 1478)

A number of references provided reported on human intervention studies which investigated the effects of BCAA mixtures on measures of physical capacity, physical performance, muscle soreness, muscle fatigue, plasma and muscle concentrations of BCAA, protein synthesis and/or protein breakdown in which changes in muscle mass were not measured. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Two human intervention studies, which aimed to investigate the effects of BCAA on surrogate measures of muscle mass (i.e. muscle cross-sectional area estimated from skin fold thickness and circumference measurements), were provided (Bigard et al., 1996; Schena et al., 1992).
The study by Bigard et al. (1996) tested the effect of BCAA supplement (BCAA, 7.8 g/d leucine, 3.4 g/d isoleucine and 11.2 g/d valine, corresponding to 35 %, 15 % and 50 % of total BCAA, respectively, 49 % energy from carbohydrate, 13 % from protein, 38 % from fat, n=11) versus a carbohydrate supplement (control, 98 % energy from carbohydrate, n=11) on surrogate measures of muscle mass in the arm in highly trained subjects who participated in six successive sessions of ski mountaineering (6-8 hr duration, altitude 2,500-4,100 m). The energy content of the total diet was controlled. The protein content in the diets including the supplements was 1.2 g per kg body weight per day in the control group and 1.44 g per kg body weight per day in the BCAA group. In the study by Schena et al. (1992) with a similar design, the effect of a BCAA supplement (BCAA, 7.8 g/d leucine, 3.4 g/d isoleucine and 11.2 g/d valine, corresponding to 35 %, 15 % and 50 % of total BCAA, 49 % energy from carbohydrate, 13 % from protein, 38 % from fat, n=4) versus a carbohydrate supplement (control, 98 % energy from carbohydrate, n=5) on surrogate measures of muscle mass in the arm and thigh was tested during altitude acclimatisation (21-day trekking). The Panel notes that the design of these small studies does not allow any conclusions to be drawn on the effects of BCAA independently of higher protein intakes and that direct comparisons between the intervention (BCAA) and control groups regarding the outcome variables were not reported. The Panel considers that no conclusions can be drawn from these studies for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of BCAA and growth or maintenance of muscle mass over and above the well established role of protein on the claimed effect.

3.3. Szybsza regeneracja mięśni po wysiłku fizycznym (ID 447, 448, 684, 1478)

Most of the references provided in relation to this claim reported on intervention studies which did not assess recovery of maximal muscle strength or power after strenuous exercise (but rather other outcomes such as perceived exertion during exercise or measures of physical capacity, physical performance, muscle soreness, muscle fatigue, plasma and muscle concentrations of BCAA, protein synthesis and/or protein breakdown) or where the effect of a mixture of amino acids, and not only BCAA, was investigated, as in Sugita et al. (2003) and Ohtani et al. (2006). The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
The remaining six references consisted of one review (Blomstrand et al., 1996) and five intervention studies (Shimomura et al., 2006; Crowe et al., 2006; Watson et al., 2004; Bigard et al., 1996; Schena et al., 1992). Two of the intervention studies were performed at high altitude and have been described in section 3.2 (Bigard et al., 1996; Schena et al., 1992).
In a small randomised, controlled, double-blinded study by Crowe et al. (2006), 13 competitive outrigger canoeists were tested before and after 6 weeks daily supplementation containing either leucine (45 mg/kg body weight/day, n=6) or cornflour (45 mg/kg body weight/day, n=7). Before and after the intervention the following tests were performed: upper body 10 s power test and a row to exhaustion at 70–75 % maximal aerobic power. The Panel notes that a test of muscle fatigue recovery was not included as an outcome parameter, and that the study was not performed with the food constituents that are the subject of the health claim (e.g. a BCAA mixture). The Panel considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
In a randomised double-blinded cross-over study by Watson et al. (2004) the effect of a sugar-free fruit drink containing 12 g/L BCAA (6 g/L leucine, 3 g/L valine, and 3 g/L isoleucine) supplementation was tested compared to placebo (sugar-free fruit drink). Eight glycogen-depleted men participated and ingested 250 mL (placebo or BCAA) at 30 min intervals, the last 2 h prior to
exercise, and 150 mL every 15 min throughout cycling to exhaustion in a warm environment (30 C).
BCAA ingestion had no effect on exercise capacity (placebo 104 27 min; BCAA 111 29 min, p=0.13). Because differences in muscle strength and power recovery between groups were not reported, the Panel considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
In a randomised, controlled, blinded cross-over study 16 women and 14 men ingested a BCAA mixture (5 g, Ile:Leu:Val = 1:2.3:1.2), which also contained 1 g of green tea powder and 1.2 g of an energy-free sweetener, or a placebo solution containing the same ingredients as the BCAA solution, but substituting 5 g dextrin for the BCAAs (Shimomura et al., 2006). The solutions were ingested 15 min before a strenuous exercise protocol intended to induce muscle fatigue. Muscle fatigue was evaluated daily using a visual-analogue scale (self-reported) up to five days post-exercise. No significant differences in (self-reported) fatigue between the BCAA and placebo groups were observed. Because changes in objective measures of muscle fatigue recovery (e.g. differences in muscle strength and power recovery) between groups were not reported, the Panel considers that no conclusions can be drawn from this study for the scientific substantiation of the claimed effect.
The Panel concludes that a cause and effect relationship has not been established between the consumption of BCAA and faster recovery from muscle fatigue after exercise.

Warunki i możliwe ograniczenia stosowania oświadczenia

77 mg per kg of bodyweight before exercise