What the research shows

In 2007, a British study published in The Lancet concluded that consuming artificial colouring and preservatives in food may increase hyperactivity in kids. Scientists have been studying the link between food additives and hyperactivity in children for more than 30 years, with mixed results. But the results of the 2007 study compelled the European Food Standards Agency to urge companies to voluntarily remove artificial colouring from food products. The FDA, however, hasn't changed its opinion on the use of FDA-approved artificial food colours, which it considers safe when used properly.

Artificial colouring

Artificial food colours are chemical dyes used to colour food and drinks, found in many types of processed foods, beverages and condiments. Supermarkets add colour to their food to make it look attractive, as if it has just been produced. For example adding preservatives and anti-oxidants to meat to give it a longer shelf life.

Food additives

Food additives have been used for centuries; for example, preserving food by pickling (with vinegar), salting, as with bacon and dried tomatoes, or using sulphur dioxide as in some wines. Food additives are substances added to food to preserve flavour or improve its taste and appearance, many more additives have been introduced, of both natural and artificial origin. Some food additives are essential, others are beneficial to us but of course there are many, which we can do without, especially those that may cause a food reaction.

E numbers

The E- stands for EC (European Community) and these numbers have been tested for safety and been passed for use in the EC. Numbers without an E in front are allowed in the UK but may have not been passed for use in all EC countries.

To regulate these additives, and inform consumers, each additive is assigned a unique number. Initially these were the "E numbers" used in Europe for all approved additives. This numbering scheme has now been adopted and extended to internationally identify all additives, regardless of whether they are approved for use.

For example, acetic acid is written as E260 on products sold in Europe, but is simply known as additive 260 in some countries. Additive 103, alkanet, is not approved for use in Europe so does not have an E number, although it is approved for use in Australia and New Zealand.

Despite their safety pass by the EC a few people suffer from allergic reactions to some of them, whether natural or synthetic. The E numbers are helpful to these people because they can easily see whether the food contains an additive to which they are allergic.

Food additives can be divided into several groups:

• Acids - Food acids are added to make flavours "sharper", and also act as preservatives and antioxidants. Common food acids include vinegar, citric acid, tartaric acid, malic acid, fumaric acid, and lactic acid.
• Acidity regulators - Acidity regulators are used to change or otherwise control the acidity and alkalinity of foods.
• Anticaking agents - Anticaking agents keep powders such as milk powder flowing freely.
• Antifoaming agents - Antifoaming agents reduce or prevent foaming in foods.
• Antioxidants - Antioxidants such as vitamin C act as preservatives by inhibiting the effects of oxygen on food, and are generally beneficial to health
• Bulking agents - Bulking agents such as starch are additives that increase the bulk of a food without affecting its nutritional value.
• Food colouring - Colourings are added to food to replace colours lost during preparation, or to make food look more attractive.
• Colour retention - In contrast to colourings, colour retention agents are used to preserve a food's existing colour.
• Emulsifiers - Emulsifiers allow water and oils to remain mixed together in an emulsion, as in mayonnaise, ice cream, and homogenized milk.
• Flavours - Flavours are additives that give food a particular taste or smell, and may be derived from natural ingredients or created artificially.
• Flavour enhancers - Flavour enhancers enhance a food's existing flavours.
• Flour treatment agents - Flour treatment agents are added to flour to improve its colour or its use in baking.
• Humectants - Humectants prevent foods from drying out.
• Preservatives - Preservatives prevent or inhibit spoilage of food due to fungi, bacteria and other microorganisms.
• Propellants - Propellants are pressurized gases used to expel food from its container.
• Stabilizers - Stabilizers, thickeners and gelling agents, like agar or pectin (used in jam for example) give foods a firmer texture. While they are not true emulsifiers, they help to stabilize emulsions.
• Sweeteners - Sweeteners are added to foods for flavouring. Sweeteners other than sugar are added to keep the food energy (calories) low, or because they have beneficial effects for diabetes mellitus and tooth decay.
• Thickeners - Thickeners are substances which, when added to the mixture, increase its viscosity without substantially modifying its other properties