Yes, all drinks have to comply with food law, just like food supplements. However they are also considered Foods For particular Nutritional uses (PARNUTS or PNUs) sometimes referred to as dietetic products under Directive 2009/83/EC. This directive establishes general rules and that one day they will get around to writing regulations ‘for foods for the expenditure of intense muscular effort’ (food for sports people). This is still at draft stage. Further guidance on this can be given on request.