Low calorie sweeteners
An alternative to the addition of carbohydrate to optimise taste is to add a low calorie sweetener, which has minimal effect on the osmolality of a drink, controls the calorific content and enables the scientific formulation and integrity to be maintained. A sub optimal taste or high calorie content is unlikely to be popular with both manufacturers and consumers and is far harder to underpin with science. Whilst low calorie sweeteners can be used to support the development of science based sports drinks for optimum hydration, their ability to control and reduce calorie content should not be over-looked. Although many people take part in sport and exercise for competitive reasons and to enhance their performance, there are also many who exercise for other goals, including weight loss and weight maintenance. Moderate intensity exercise in a gymnasium environment can use approximately 10 calories per minute, or 300 calories in total for a 30 minute session. A 500ml bottle of isotonic drink consisting of 6.5% carbohydrate (i.e. 6.5 grammes of carbohydrate per 100ml of fluid) will contain approximately 130 calories of energy or almost half of the energy burnt during the session, which is equivalent to the energy expended during a 1 mile run for an average person. Where the main priority is to replace fluid and electrolytes and not fuel, a low calorie hypotonic solution, flavoured water or water, may be the best option. In this circumstance, regulation of taste can be achieved with low calorie sweeteners, sustaining taste whilst simultaneously reducing the energy content of a drink. A recent review (13) highlighted the potential impact of the acidity and sugar content of a drink on dental erosion (acidity) and caries (sugar). Along with good oral hygiene and appropriate usage, a reduction in sugar content, through the use of low calorie sweeteners, can help to mitigate much of this risk.