A food additive is any substance that a food manufacturer intentionally adds to foods to achieve specific desired effects or characteristics during production or processing. In general, food additives contribute to the shelf life of foods and have made many convenience foods possible. They also maintain the firmness, softness or texture of many foods.

Some people prefer to avoid food additives, when possible. If this is your preference, you should read labels carefully and select more foods in the natural foods section of your store.

Food additives in ancient times:

Many food additives have been used for centuries. For example:

• The Egyptians used vegetable food colorings
• The Romans used honey to preserve fruit
• Salting food was a common practice in the Middle Ages
• Marco Polo searched for herbs and spices, additives for flavouring foods

Types of food additives:

Food additives are used for a number of different reasons including food preservation, spoilage prevention, flavour enhancement and to improve nutritional value. There are approximately 3,000 food additives that are classified into six major categories

1. Nutritional supplements

Many foods are fortified with vitamins and minerals. The primary reason for this practice is to replace nutrients lost during processing and to prevent deficiency diseases. Some of the common fortifications are: vitamin D in milk, vitamin A in margarine, iron and B vitamins in breads, and iodine in table salt.

2. Preservatives

The safe-use period of many foods is greatly extended through the addition of preservatives, which retard spoilage, preserve flavour and colour and keep oils from turning rancid. Preservatives protect foods, such as cured meats, from developing dangerous toxins, such as botulism, a food poisoning illness.

3. Flavouring agents

These are the most commonly used additives. Some, such as monosodium glutamate (MSG), are used to enhance flavour. Others, like chemical concentrates of a flavour such as strawberry, are used to boost flavour. Flavourings are often used when a natural flavouring is unavailable or too expensive to use in a particular commercial product.

4. Colouring agents

These additives are used strictly to make foods more attractive to the consumer. Even some fruits, like oranges, have colour added to their skins to make their colour match the expectations of consumers.

5. Emulsifiers, stabilisers, and thickeners

A large variety of products from this category are used to improve the texture and consistency of foods. Emulsifiers are commonly used to keep ingredients from separating in sauces and salad dressings. Lecithin, gelatine and pectin are commonly used natural emulsifiers.

6. Acids and alkalis

These additives are used to neutralize the acidity or alkalinity of certain foods. Citric acid, for instance, might be used to add tartness to certain foods.

Government control of additives:

The Food, Drug, and Cosmetic Act of 1938 is the law that sets the standards for food in the United States, while at the same time calling for truthful labeling. This act gives the U.S. Food and Drug Administration (USUSFDA) responsibility for safety and wholesomeness of foods. There have been a few amendments to this act, but one, in particular, strengthens it in regard to additives. The Food Additives Amendment of 1958 requires pre-marketing approval for substances intended to be added to foods. This amendment includes the Delaney Clause, which states that no chemical can be added to food if, in any amount, it produces cancer when ingested by man or animal.

When the Food Additives Amendment of 1958 was adopted, over 200 substances were exempted from the testing requirement because they were considered to be Generally Recognised as Safe (GRAS). A number of other substances have been added to this list since its initial adoption.

Allergies and sensitivities to additives:

Some people have an immediate reaction to food preservatives, such as BHA, BHT, MSG, nitrites, sulphites, sodium bisulphite, and sulphur dioxide. Some of these reactions are due to allergies. With allergies, preexisting antibodies in the body react to the chemical molecules and cause a variety of problems, ranging from mild skin rashes to gastro-intestinal upset to life-threatening anaphylactic episodes.

Other reactions reflect an “intolerance” to the food or additive; rather than an allergy per se, but these reactions may still be uncomfortable. An example of such a reaction would be a person who gets a headache after eating MSG.

The best course for concerned individuals is to read all labels carefully and to choose foods that are additive-free.

Ensminger Audry, ME Ensminger, James E. Konlande, and John R. K. Robson. The Concise Encyclopedia of Foods and Nutrition. New York: CRC Press. 1995.