It’s a national pastime. You buy a snack; then, while enjoying it, you read the label. “Contains Yellow #6, sodium benzoate and potassium sorbate.” (All of which I found listed on a bottle of iced tea I bought recently.) It doesn’t usually stop you from eating or drinking (not me, anyway) but it does make you wonder.
A food additive is a non-food substance added to food during processing. Additives preserve food, improve its colour, and enhance flavour or texture. More than 2,500 are known.
Salt, which preserves food and enhances flavour, was probably the first additive. Amazingly, the ancients also knew to preserve meat by adding a chemical called guaiacol (2-methoxyphenol), which kills bacteria and limits oxidation. Of course, they called it “smoke.”
Salt and sugar preserve food by tying up water molecules that would otherwise be used by microorganisms. Additives that destroy microorganisms include ethyl formate, sodium and calcium propionate, sodium nitrite or nitrate, sorbic acid, sulfur dioxide–and sodium benzoate, contained in that iced tea I bought.
Antioxidants keep foods from becoming rancid, turning brown or developing black spots. One common antioxidant is butylated hydroxynisole, or BHA. Antioxidants can also prevent the loss of some nutrients, such as amino acids and vitamins. Sometimes, vitamins themselves are food additives: Vitamin D is added to milk, many drinks are enhanced with Vitamin C, and Vitamin A is added to margarine.
Food additives also make foods more appealing by altering their colour (hence “Yellow #6” in my iced tea) or enhancing their flavour. One of the most common flavour-enhancers is monosodium glutamate, or MSG.
Glutamate is a constituent of all protein, so it occurs naturally in food. Monosodium glutamate is a white, crystalline powder derived from the fermentation of basic foods such as molasses.
Some people claim to be sensitive to MSG. There’s even something called “Chinese Restaurant Syndrome”: chest pain, facial pressure, burning sensations suffered after eating Chinese food, which usually contains MSG. However, careful testing of people who claimed to have this sensitivity failed to find it under controlled conditions. Worldwide, MSG has been consistently placed on the list of very safe food additives.
But there’s another question. In 1969 a scientist at Washington University, John Olney, found that when MSG was given to monkeys or rats, especially to infants, certain nerves in their brains were destroyed–the heightened level of glutamate in the blood literally excited the nerves to death. Later studies, while confirming “exitotoxicity,” failed to confirm any connection between it and MSG ingestion in humans. But it’s possible certain people are more susceptible than others. Scientists continue to study the question, which happens to tie in with another common type of flavour-enhancing food additive, sweeteners.
Artificial sweeteners are a common food additive due to the national obsession with losing weight. One of them, aspartame, contains an amino acid that can cause exitotoxicity, just like MSG, although, again, there’s no solid evidence that ingesting aspartame has that result. A couple of other sweeteners, cyclamates and saccharin, have been found to cause cancer when given in very large amounts to laboratory animals, and cyclamates were banned as a result.
Texture-enhancing additives include gelatin, often added to ice cream to make it smoother. Some new texture-enhancing additives are designed to replace fat. One, not yet approved, is Olestra, which looks and tastes like real fat, but can’t be absorbed by the body.
Public concern about additives is widespread, though often both highly selective and misplaced. The current flap over milk produced by cows treated with bovine somatotropin (BST), which boosts milk production, is an example. Milk has always contained BST; cows produce it naturally. Milk from BST-treated cows is therefore considered the same as any other milk by regulators–but some grocery stores refuse to carry it because of public concern. Yet at the same time, the public actually forced the U.S. Congress to reverse the FDA’s ban on saccharin, a substance which was proven to cause cancer in laboratory animals.
Of course we should be concerned about what’s in our food–but common sense should apply. For the most part, food additives are well-tested–and are constantly being re-tested. The risk posed by the possibility some danger in a currently approved additive has been overlooked is far less than the risk posed just by getting out of bed.
So don’t panic when you read the label on your snack. Those mysterious ingredients are working for you, not against you, killing bacteria, enhancing flavour or making the food more appetizing.
In fact, I think I’ll have another bottle of that iced tea.