2.1. Zwiększenie sytości prowadzące do redukcji przyjmowanej energii (ID 425)

The claimed effect is “increases satiety”. The Panel assumes that the target population is the general population.
Satiety is the decrease in the motivation to eat after consumption of food. The effect may persist up to several hours, may reduce energy intake either at the next meal or across the day and, if sustained, may lead to a reduction in body weight.
The Panel considers that an increase in satiety leading to a reduction in energy intake, if sustained, might be a beneficial physiological effect.

2.2. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 1683)

The claimed effect is “weight management”. The Panel assumes that the target population is the general population.
Weight management can be interpreted as contribution to the maintenance of a normal body weight. In this context, weight loss in overweight individuals even without achieving a normal body weight is considered to be a beneficial physiological effect.
The Panel considers that contribution to the maintenance or achievement of a normal body weight is a beneficial physiological effect.

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.

2.4. Zwiększenie beztłuszczowej masy ciała podczas diety niskoenergetycznej i treningu siłowego (ID 421)

The claimed effect is “supports a gain in lean body mass during periods of energy restriction”. The Panel assumes that the target population is adults on an energy-restricted diet performing resistance training who wish to increase their lean body mass.
The Panel considers that an increase in lean body mass during energy restriction and resistance training is a beneficial physiological effect.

2.5. Redukcja tkanki tłuszczowej podczas diety niskoenergetycznej i treningu siłowego (ID 420, 421)

The claimed effect is “supports a decrease in body fat when combined with exercise and a hypocaloric diet”. The Panel assumes that the target population is adults on an energy-restricted diet performing resistance training who wish to decrease their body fat mass.
The Panel considers that a reduction in body fat mass during energy restriction and resistance training is a beneficial physiological effect.

2.6. Zwiększenie siły mięśni (ID 422, 429)

The claimed effect is “muscle strength”. The Panel assumes that the target population is active individuals who are performing resistance exercise to improve muscle strength.
The Panel considers that an increase in muscle strength is a beneficial physiological effect.

2.7. Wzrost wytrzymałości podczas kolejnych ćwiczeń fizycznych po dużym wysiłku (ID 428)

The claimed effect is “physical performance”. The Panel assumes that the target population is active individuals in the general population.
In the context of the proposed wording, the Panel assumes that the claimed effect refers to an increase in endurance capacity.
The terms endurance performance and endurance capacity are often used as synonyms. However, endurance capacity refers to the exercise time to volitional fatigue when exercising at a constant workload or speed, whereas endurance performance relates to the ability of completing a certain task (e.g. running a certain distance) as fast as possible. In the context of the proposed wording, the Panel assumes that the claimed effect refers to an increase in endurance capacity during the subsequent exercise bout after strenuous exercise.
The Panel considers that an increase in endurance capacity during the subsequent exercise bout after strenuous exercise is a beneficial physiological effect.

2.8. Naprawa tkanki mięśniowej poprzecznie prążkowanej (mięśni szkieletowych) (ID 428)

The claimed effect is “physical performance”. The Panel assumes that the target population is active individuals performing resistance exercise.
In the context of the proposed wording, the Panel assumes that the claimed effect refers to the rebuilding of structural protein within the skeletal muscle tissue after exercise that has caused muscle damage.
The Panel considers that skeletal muscle tissue repair is a beneficial physiological effect.

2.9. Szybsza regeneracja mięśni po wysiłku fizycznym (ID 423, 428, 431)

The claimed effects are “muscle fatigue recovery” and “muscle recovery”. The Panel assumes that the target population is active individuals in the general population.
The Panel assumes that the claimed effects refer to muscle fatigue recovery.
Fatigue can be defined as the loss of peak force or power output. Therefore, muscle fatigue recovery can be defined as the regaining of maximal muscle strength or muscle power after strenuous exercise that has induced muscle fatigue. Regaining muscle strength/power may be beneficial during every day life activities, and is beneficial for athletic performance in disciplines where loss of muscle strength and power reduces performance.
The Panel considers that faster recovery from muscle fatigue after exercise is a beneficial physiological effect.

3.1. Zwiększenie sytości prowadzące do redukcji przyjmowanej energii (ID 425)

The references provided include intervention studies and reviews on the effects of dietary protein in general and on whey protein specifically, but on outcomes other than measures of satiety (e.g. protein turnover, muscle synthesis, glucose metabolism and immune effects). The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
Among the references submitted, four addressed the effects of whey protein on measures of satiety (in the next 2-3 hours) and subsequent ad libitum energy intake when administered as a liquid pre-load on a single occasion, compared to isocaloric, liquid control pre-loads (e.g. glucose, casein, soy protein, gluten), following a randomised cross-over design (Hall et al., 2003; Bowen et al., 2006a, b; Bellissimo et al., 2008).
The Panel notes that none of these studies tested the sustainability of an effect of whey protein on measures of satiety and subsequent energy intake (effects were only tested on a single occasion and no information was provided on the repeated consumption of the food constituent). 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 whey protein consumption and a sustained increase in satiety leading to a reduction in energy intake.

3.2. Udział w utrzymaniu lub osiągnięciu prawidłowej masy ciała (ID 1683)

The references provided included intervention studies and reviews on the effects of dietary protein in general, on the effects of dairy products and calcium on adiposity and weight management, and on whey protein specifically, but on outcomes other than measures of body weight (e.g. glucose homeostasis, appetite and food consumption). The Panel considers that no conclusions can be drawn from these references 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 whey protein and contribution to the maintenance or achievement of a normal body weight.

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.

3.4. Zwiększenie beztłuszczowej masy ciała podczas diety niskoenergetycznej i treningu siłowego (ID 421)

Most of the references provided for the scientific substantiation of this claim did not address the effects of whey protein specifically (but rather those of protein in general), or did not have lean body mass as an outcome measure. In some of the references provided which assessed the effects of whey protein on lean body mass compared to another isonitrogenous protein source (i.e. casein and soy protein) (Cribb et al. 2006; Candow et al., 2006), or to a non-protein isocaloric control (i.e. carbohydrates) (Cribb et al., 2007; Burke et al., 2001); energy restriction was not part of the intervention. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
One human intervention study (Demling and DeSanti, 2000) addressed the effects of whey protein consumption on lean body mass in humans compared to another isonitrogenous protein source (i.e. casein) in the context of an energy-restricted diet. This study has been described in section 3.3 and reported a significantly greater increase in lean body mass in the casein group compared to the whey protein group.
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein and an increase in lean body mass during energy restriction and resistance training.

3.5. Redukcja tkanki tłuszczowej podczas diety niskoenergetycznej i treningu siłowego (ID 420, 421)

Most of the references provided for the scientific substantiation of this claim did not address the effects of whey protein (but rather of other food constituents or combinations, some including whey protein), and/or did not provide data on body fat changes. In some of the references provided which assessed the effects of whey protein on body fat mass compared to another isonitrogenous protein source (i.e. casein and soy protein), or to a non-protein isocaloric control (i.e. carbohydrates), energy restriction was not part of the intervention (Cribb et al. 2006; Cribb et al., 2007; Burke et al., 2001; Candow et al, 2006). The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claimed effect.
One human intervention study (Demling and DeSanti, 2000) addressed the effects of whey protein consumption on lean body mass in humans compared to another isonitrogenous protein source (i.e. casein) in the context of an energy-restricted diet. This study has been described in section 3.3 and reported a significantly greater decrease in body fat mass in the casein group compared to the whey protein group.
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein and the reduction of body fat mass during energy restriction and resistance training.

3.6. Zwiększenie siły mięśni (ID 422, 429)

A number of references provided for the scientific substantiation of this claim either addressed the effects of foods other than whey protein alone (e.g. whey protein enriched or in combination with certain amino acids, such as cysteine, or branched chain amino acids) and/or reported on health
outcomes other than muscle strength. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
Two human intervention studies (Cribb et al. 2006, Demling and DeSanti, 2000) addressed the effects of whey protein consumption on muscle strength in humans compared to another isonitrogenous protein source (i.e. casein). Both have been described in section 3.3. Whereas the study by Cribb et al. (2006) reported a significantly higher increase in muscle strength with the consumption of whey protein supplements compared to casein supplements in the context of a normocaloric diet, conflicting results were obtained in the study by Demling and DeSanti (2000) in the context of an energy-reduced diet. Both studies were performed in male subjects following a resistance training programme.
One human intervention study investigated the effects of whey protein compared to another isonitrogenous protein source (i.e. soy protein) and to isocaloric carbohydrate supplements (Candow et al., 2006). This study has been described in section 3.3. No significant differences in muscle strength were observed between the whey protein and the soy protein groups.
Two human intervention studies compared the effect of whey protein on muscle strength compared to isocaloric carbohydrate supplements (Cribb et al., 2007; Burke et al., 2001). The Panel considers that no conclusions can be drawn from these studies for the scientific substantiation of the claimed effect as they were not controlled for nitrogen intake.
In weighing the evidence, the Panel took into account that the results from the three small intervention studies in humans that addressed the effects of whey protein versus other protein sources (i.e. casein and soy protein) on muscle strength were conflicting.
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein during resistance training and an increase in muscle strength.

3.7. Wzrost wytrzymałości podczas kolejnych ćwiczeń fizycznych po dużym wysiłku (ID 428)

Most of the references provided for the scientific substantiation of this claim addressed the effects of protein sources other than whey, used whey protein in combination with other food constituents (e.g. carbohydrates, specific amino acids) or enriched in specific amino acids (e.g. cysteine). Other references addressed the effects of whey protein supplements used as pre-load on endurance capacity and/or performance during exercise, but not at a subsequent exercise bout. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
The Panel concludes that a cause and effect relationship has not been established between post exercise consumption of whey protein and an increase in endurance capacity during the subsequent exercise bout after strenuous exercise.

3.8. Naprawa tkanki mięśniowej poprzecznie prążkowanej (mięśni szkieletowych) (ID 428)

Some of the references provided for the scientific substantiation of this claim addressed the effects of whey protein or of protein other than whey, either alone or in combination with carbohydrates compared to carbohydrates alone or compared to other protein sources, on indirect measures of muscle damage (e.g. concentration of intracellular muscle enzymes in the blood, muscle pain, muscle strength or other performance parameters) which are not necessarily related to improved repair of skeletal muscle structures. The remaining references were narrative reviews that did not provide original data for the substantiation of the claimed effect. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein after resistance exercise and skeletal muscle tissue repair.

3.9. Szybsza regeneracja mięśni po wysiłku fizycznym (ID 423, 428, 431)

Some of the references provided for the scientific substantiation of this claim addressed the effects of whey protein on health outcomes unrelated to the claimed effect (e.g. concentration of intracellular muscle enzymes in the blood, muscle pain, muscle strength or other performance parameters) or on the effects of protein hydrolysates in combination with carbohydrates compared to carbohydrates alone given after an initial strenuous exercise bout on performance parameters at a subsequent exercise bout after a recovery period. The Panel notes that, although these latter studies used an appropriate design to test muscle fatigue recovery, the effects of whey protein were not assessed (Ready et al 1999; Romano-Ely et al. 2006; Saunders et al. 2004). The remaining references were narrative reviews which did not provide original data for the substantiation of the claimed effect. The Panel considers that no conclusions can be drawn from these references for the scientific substantiation of the claim.
The Panel concludes that a cause and effect relationship has not been established between the consumption of whey protein and faster recovery from muscle fatigue after exercise.