At some point or other most runners have considered taking a sports supplement and from energy gels and drinks through to more complex substances, the choice is huge and often confusing.
In a short article on the subject, sports nutrition expert Andrew Hamilton, argues that sports people should take a step back when considering taking a sports supplement and consider first how good their day to day diet is. His suggestion is to consider nutritional needs as a type of pyramid. The base of the pyramid represents basic dietary needs, with successive layers above the base being made up of more specialised needs, the latter being only of use if the base is fully in place.
With this approach the use of sports supplements really does become the absolute icing on the nutritional cake.
The article is worth a read and contains links to other useful nutritional guides. http://www.excelsiorgroup.co.uk/blog/walk-you-run-sprts-nutrition-guide-andrew-hamilton