EFSA provides nutrient advice for muscle and performance health claims
In offering support very much geared towards the sports nutrition industry, the Authority has updated existing scientific requirements for physical performance-related health claims published in 2012.
“This guidance focuses on key issues, particularly claimed effects which are considered to be beneficial physiological effects,” the scientific opinion outlined.
“In addition to definition of the target population for which the claim is intended, the characteristics of the human intervention studies can provide evidence for the scientific substantiation of specific claims addressed in this guidance (e.g. appropriate outcome variables and methods of measurement, suitable study group(s) and suitable controls).”
Scope for updating
While the draft guidance was released for public consultation (from 16 July to 2 September 2018), EFSA added that the guidance was by no means the finished article.
They added there would be further updates as appropriate in the light of experience gained from the evaluation of health claims in this area.
Among the 490 health claim applications related to muscle function and physical performance submitted to EFSA as of 8 February 2018, only 12 were considered relevant to this guidance.
EFSA added that the Panel withdrew five during the evaluation process whilst seven were evaluated/finalised.
Among those finalised, three were evaluated by the Panel with a favourable outcome and all three referred to claims other than those based on the essentiality on nutrients. Two were on muscle function and one on physical performance.
These were carbohydrate solutions (improvement of physical performance during a high‐intensity and long‐lasting physical exercise), creatine, (increase in physical performance during short‐term, high intensity, repeated exercise bouts) and (improvement in muscle strength (in combination with resistance training)).
Assessment criteria clarification
In an effort to improve these numbers, the assessment criteria was clarified, with a focus on function claims based on the essentiality of nutrients.
“Several health claims related to essential nutrients have been scientifically substantiated based on the principle of the essentiality of these nutrients,” the opinion said.
“The nutrient is required for normal human body function(s), i.e. it has an essential mechanistic role in a metabolic function and/or it has the ability to reverse clinical signs and symptoms of its deficiency.
“The nutrient cannot be synthesised by the body or cannot be synthesised in amounts which are adequate to maintain normal body function(s) and (iii) the nutrient must be obtained from a dietary source.”
For these claims, the Panel did not review the primary scientific studies submitted and it did not weigh the evidence.
Nutrient claims relating to muscle function also received clarification with improvement, maintenance or reduced loss of muscle function (contraction) considered a beneficial physiological effect.
“Failure to increase muscle mass during growth and development, and the loss of muscle mass at any age, will impair muscle function (e.g. muscle strength and power),” EFSA said.
“Faster recovery of normal muscle function after exercise is also considered a beneficial physiological effect.”
Claims on the well‐established role of some minerals such as sodium, potassium, magnesium and calcium on the maintenance of normal muscle function (contraction) have previously been evaluated by the Panel with a favourable outcome.
The target population for these claims was the general healthy population. Conditions of use were established on the basis that any significant amount of the essential nutrient in the diet would contribute to the claimed effect (i.e. conditions of use were linked to nutrition claims).
Dietary protein claims
Commenting on a claim that dietary protein contributed to a growth or maintenance of muscle mass, which received a favourable outcome back in 2010, the Panel considered that the role of dietary protein in the growth (during development) and maintenance (after adolescence) of whole body lean body mass, including muscle mass, was well‐established.
“Maintenance of lean body mass can be achieved if (protein) nitrogen intake is equal to or above (protein) nitrogen losses over a period of time.
“It is well documented that protein intake is necessary to maintain nitrogen (protein) balance as nitrogen is lost from the body primarily via the urine, but also in small amounts via faeces, sweat, skin, hair and nails.
Similarly, EFSA maintained that maintenance of muscle mass was typically achieved if mean muscle protein synthesis rate was equal to mean muscle protein breakdown rate over a period of time.
The Authority said that protein intakes within the Dietary Reference Values (DRVs) allowed for growth and maintenance of lean body mass, including muscle mass, for normal protein turnover, and for muscle recovery after physical exercise.
“The target population for this claim was the general healthy population. Conditions of use were established on the basis that any significant amount of protein in the diet will contribute to the claimed effect (i.e. conditions of use were linked to nutrition claims).”