Caffeine and sport: recent studies

New interesting evidence related to the involvement of caffeine in sport performance has been published during the last month.

The first of these studies suggests that 6 mg/kg BW caffeine supplementation improves by ~2% rowing (2000 m effort)
performance; combination with sodium bicarbonate seems to prevent performance enhancement, due tu GI side effects.
Further investigation to minimize GI symptoms is required. Health claims on caffeine have received favorable opinions by EFSA but have caused concerns with Member States.
The second one reports that adding 8 mg/kg BM caffeine to postexercise carbohydrate (CHO) feedings seems to improve subsequent high-intensity interval-running capacity compared with CHO alone. This effect may be related to higher rates of postexercise muscle glycogen resynthesis previously observed under similar feeding conditions. In line with EFSA health claim assessment (still controversial with Member States) it may be interesting to suggest on label to take
caffeine supplements after the intake of CHO, or with CHO. Nevertheless the recommended dosage in the study seems to be too high (560 mg/day for a 70 kg person).

In both studies a potential concern seems to be related to the levels of caffeine used. For example EFSA, in its opinions, takes into
account lower levels of caffeine compared to those used in trials; Member States allow lower amounts of caffeine in food supplements (Belgium bans solid caffeine). In Italy, for example, no more than 300 mg/day caffeine are informally allowed.

These studies provide further support to the use of caffeine in sports under some circumstances, although levels may be an issue.


Armando Antonelli – Sport Nutrition Team

Oxidative damage (included UV-induced): health claims guideline.

EFSA has published a guidance to explain what are the scientific requirements for health claims referring to: antioxidant, oxidative damage and cardiovascular health.

First of all EFSA states (in accordance with Reg. 1924/2006) that the 2 main requirements to substantiate a claim are that the claimed effects have to be considered as a beneficial physiological effects and that it must be supported by adequate studies in humans.

In the first part of the document the status of ‘antioxidant’ is discussed: the concept of “antioxidant” as a benefit is rejected, but this aspect will be discussed more specifically in another post.

Regarding protection from oxidative damage, which can be claimed and is intended as proven protection of body cells and molecules (i.e. DNA, proteins and lipids) from oxidative damage, EFSA established some general requirements to substantiate these claim with reference to all the cellular structures:

–          An appropriate method of assessment should be able to determine accurately and specifically the oxidative modification of the target molecule in vivo (at least an appropriate market of oxidative modification needed).

–          A marker (method) cannot be accepted for substantiation when (technical) limitations are considered to be severe.  

 Then, as reported above, the food/constituent has to show a real beneficial effect on target molecules and it has to be demonstrated by  setting up adequate scientific studies, involving humans. Below the methods accepted to validate the beneficial physiological effect, specific for every different cellular body:

–          Proteins: the only validated method to detect oxidative damage is HPLC-MS. Proteins by products analysis (ELISA or other colorimetric methods) shows some limitation, then they cannot be considered valid alone, but just in combination with other direct methods.

–          Lipids: F2-isoprostanes in 24-h urine samples is the recommended method. LDL oxidised particles (using specific antibodies) and phosphatidylcholine hydroperoxides (using HPLC) are validated methods as well. Not allowed markers: reactive substances (TBARS), malondialdehyde (MDA), lipid peroxides, HDL-associated paraoxonases, conjugated dienes, breath hydrocarbons, auto-antibodies against LDL particles, and ex vivo LDL resistance to oxidation).

–          DNA: recommended method is the modified comet assay which allow the detection of oxidised DNA bases (e.g. use of endonuclease III to detect oxidised pyrimidines). Conventional comet assay and other methods are not suitable.

Other methods still widely used to measure antioxidant properties are to be considered worthless in the perspective of health claims. This applies to the evaluation of past studies, and future studies of benefits of food.

Armando – Sport Nutrition team

Food additives: EC adopts a new Regulation

The European Commission has  adopted a new Regulation, implementing Regulation EC 1333/2008. The new Regulation includes list of food additives intended for foodstuffs and food ingredients. The lists will replace lists under  Directives 95/2/CE, 94/36/CE and 94/35/CE in 2013.

The Regulation also foresees that anti-caking agent silicon dioxide can be used for salt substitutes at higher levels and that the coating agent basic metacrilate can be used for food supplements. These specific rules will come into force 20 days after the publication of the present regulation, on December 2 2012; the general list apply on 1 June 2013. Products legally marketed before 1 June 2013 can continue to be sold.

It is interesting to note that the list is divided into categories for different foodstuffs. The category for food supplements is number 17 (solid form such as capsules and tablets, liquid form, syrup or chewable). It is noteworthy that category 13 is food with particular nutritional purposes; foods for sportsmen are not included, further confirmation of the upcoming abolition of this category (if not abolished, theoretically from June 1  2013, no additives would be allowed in foods for sportsmen, as well as in other dietetic foods for which specific rules have not been set).

Armando Antonelli- Sport Nutrition Team

EFSA: caffeine for sports ok, but not for weight loss

The 8 of April 2011 EFSA’s NDA Panel has published the outcome of the evaluations of a fourth series of ‘general function’ health claims proposed for use on food products.

Only few opinions are positive for sports nutrition. Among these 442 health claims, the most relevant are related to caffeine; in particular  health claims such as ‘Increased alertness’ , ‘ increased attention’, ‘increase in endurance performance’, ‘increase in endurance capacity’, ‘reduction in the rated perceived exertion/effort during exercise’ are now accepted for caffeine. Other positive outcomes are related to resistant maltodextrins ( ‘Changes in bowel function’), Choline (‘ Contribution to normal lipid metabolism ‘) and olive poliphenols  ( ‘Hydroxytyrosol protects LDL particles from oxidative damage’).

Instead most EFSA opinions are negative. It should be noted that all the health claims on ‘reduction of body weight’ related to caffeine and green tea have been rejected. Other negative outcomes are related to several aminoacids such as  L-Arginine, Lysine, Tryptophan and aminoacidic derivatives such as Taurine and Carnosine, particularly interesting are the rejected health claims concerning  ‘management of body mass’  and “improvement of endothelium-dependent vasodilation’ (Arginine),  ‘Contribution to normal protein synthesis’ (Lysine), ‘Maintenance of normal muscle function’ (Taurin). Also Quercetin, Lutein, Alpha Linoleic Acid (ALA), FOS and PUFAs DHA/EPA (Omega 3) received general negative opinions from the Panel.

“The positive opinion on caffeine is important specifically for the benefits which EFSA has recognized within the domain of the Nutrition and Health Claims Regulation, and the standard that it sets.” commented Luca Bucchini, managing director of Hylobates “Though EFSA’s opinions are important when thinking to new products, they should not be the only driving force. EFSA’s processs is welcome when compared to the less than transparent situation in several EU countries; at the same time, it should be noted that EFSA’s approach has been less than consistent between micronutrients and other substances. It is time for the sports nutrition industry to think carefully about the future.”

– Armand and Jacopo, Sport Nutrition Team –

EFSA: la caffeina per lo sport funziona, altre sostanze no

In data odierna il gruppo di esperti dell’EFSA ha pubblicato i risultati della valutazione di 442 claim sulla salute proposti per l’uso nei prodotti alimentari.

Solo poche opinioni possono essere considerate positive nel campo della nutrizione sportiva,  in particolare sono stati accettati claim relativi al consumo di caffeina e aumento dello stato di allerta/attenzione, diminuzione della percezione dello sforzo durante l’esercizio fisico ed aumento della capacità in esercizi fisici di resistenza. Gli esperti dell’EFSA hanno dato inoltre parere positivo per il claim relativo alle maltodestrine resistenti affermando che c’è una relazione di causa effetto tra il consumo di questi carboidrati e il miglioramento della funzionalità intestinale. Altri esiti positivi sono riscontrabili per claim relativi alla Colina (‘contribuisce al normale metabolismo lipidico’) e ai polifenoli dell’ulivo (‘Idrossitirosolo protegge le LDL dal danno ossidativo’).

Gran parte dei claim valutati sono stati respinti, tra cui i principali relativi al consumo di caffeina e tè verde che riguardano ‘mantenimento e controllo del peso corporeo’ non potranno più essere utilizzati per prodotti ed integratori alimentari, a meno che il processo a livello comunitario abbia un esito diverso e solo quando i pareri diventeranno legge, con lo specifico regolamento di attuazione. Nessun parere positivo per quel che riguarda i claim  sugli aminoacidi come arginina, lisina, triptofano e derivati aminoacidici quali taurina, carnosina: infatti i principali claim sulla massa muscolare, attività di tipo tonico e vasodilatazione sono stati bocciati.Numerosi altri claim sono stati valutati e bocciati, in particolare molti relativi a Quercetina, Luteina, Acido Alfa Linoleico (ALA), FOS e i PUPA DHA/EPA (Omega 3) generalmente per carenza di dati sufficienti.

“Non bisogna dimenticare che EFSA ha ampiamente riconosciuto i benefici di vitamina e minerali che sono i tipici principi degli integratori alimentari, anche per lo sport (come per vitamina C e sistema immunitario dello sportivo)” ha commentato Luca Bucchini, direttore gestionale di Hylobates “Per le altre sostanze ha usato uno standard di prova molto diverso e a volte discutibile, anche se riteniamo un processo trasparente e scientificamente qualificato come quello di EFSA sia importante e necessario. Il riconoscimento per la caffeina è importante ed univoco; sarà importante bilanciare l’effetto positivo dei pareri EFSA con la necessità di portare sul mercato prodotti equilibrati, indirizzando attentamente la ricerca. Su un piano più squisitamente tecnico è importante, che con l’opinione sulla caffeina, EFSA ha confermato la possibilità di claim sulla salute nel quadro del Regolamento 1924/2006 riferiti ad attività sportive”.

Le indicazioni fornite dal Ministero della Salute sul proprio sito, fino all’entrata in vigore di un regolamento applicativo (atteso per metà 2012), restano permesse.

– Armando e Jacopo, Sport Nutrition Team –

Aggiornato alle ore 18:03 dell’8/4 con riferimento al Ministero Salute

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