Functional beverages are typically vegetable or fruit-based drinks that have an added ingredient targeted to attain a specific function important to health.
Various types of ingredients are used, for example: amino acids, vitamins, mineral salts, anti-oxidizing molecules, fibres, probiotic microorganisms, and prebiotic factors (dissolvable fibre).

Functional drinks encounter a rising demand since consumers search for healthy and natural products without having to resort to diet foods, which are commonly associated with poor taste and have a punitive look-and-feel.

Sport drinks are beverages designed to act as a supplement to replace water, electrolyte, and energy after exercise and comprise a vast array of products that range from the complex nutritional solutions for professionals to the most common isotonic products for occasional consumers. These products are widespread among the large retail distribution chains.
There are functional differences in this kind of beverages:

Isotonics: these have the same saline concentration as body fluids; therefore they rapidly re-integrate liquids and minerals lost through sweating and supply energy thanks to their carbohydrate content;

Hypotonics: these contain molecules in inferior concentrations as compared to those found in blood; thereby their re-integration action is faster than those of isotonics, but not so beneficial as carbohydrates.

Hypertonics: (with more molecules as compared to blood) normally used to intake carbohydrates after physical exercise in order to top up muscle glycogen stores.

One of the key marketing and manufacturing factors that promote the functional drinks market is the fact that they do not use preservatives or caffeine and are prepared without carbonation. Market hurdles include balancing the sugar content, function and flavor; but, the potential for expansion into emerging markets is expected to help overcome these issues.