Ingredients in Colas
American's drink around 40 litres of the lip-smacking' liquid a year. And this is what you're probably getting with it .
Water: Almost 90 per cent of cola is carbonated water. Unexceptional stuff, although cola is a good bet in countries with poor drinking water. Adding carbon dioxide to water produces carbonic acid which, although weak, can erode teeth.
Sweetener: Normally sugar, about 35 mg in a 330 ml can, equivalent to seven teaspoons in a mug of tea. This packs some 140 Calories. `Cola is an archetype of the "empty calories" products', says Jack Winkler of Action and Information on Sugars. `Cola is a significant source of calories with no nutritional value'. It has been argued that cola raises blood sugar levels and so decrease your appetite for more nutritious foods. What's more sweeteners may impair the body's appetite control mechanism and encourage noshing. Sugar is also the great teeth rotter. `Don't drink cola frequently between meals,' says Winkler, `Your saliva doesn't get a chance to fight back to protect your teeth. "Sugar free colas don't let your teeth off the hook, either. All colas are acidic and have the potential to erode teeth", says Dr. Peter Gordon, scientific advisor to the British Dental Association. Diet colas contain artificial sweeteners, mainly aspartame (NutraSweet). In the USA, sugar packets with NutraSweet contain warnings that it may be carcinogenic.
Flavourings: Phosphoric acid balances the cola's sweetness to provide the characteristic tart taste. This acid is so strong you can clean a toilet with it or dissolve a tooth in 48 hours, says Janet Thorn, senior lecturer in nutrition at Oxford Brookes University.
Stimulants: Between 40 mg and 60 mg of caffeine are added to each can (a cup of instant coffee contains 60-65 mg). `I think the presence of caffeine is slightly sinister because it's added as a stimulant,' says Ian Shaw, Professor of Toxicology at Central Lancashire University.
Colouring: The brown colour comes from caramel, basically burnt sugar, which has a bitter taste. Caramel is widely used in soft and alcoholic drinks, sauces and canned meats. There have been suggestions that it is carcinogenic and causes white blood cell problems in animal tests.
Preservatives: Sodium benzoate stops contamination by microbes. It's considered safe, although there have been claims that it provokes allergies, asthma and skin reactions. It is definitely toxic to cats.
Nutrients: `Colas are basically an expensive way of buying sugared water,' says Janet Thorn.
Further Reading
Artificial Sweeteners - Aspartame, NutraSweet, Equal, Spoonful
Sugar and Sweeteners