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Unless you grow your own food and prepare all your meals from scratch, it's pretty much impossible to eat foods that don't have chemical additives. You'll find caramel colour in bread, xanthan gum in salad dressings, carrageenan in almond milk, maltodextrin in ice cream and butylated hydroxytoluene in breakfast cereals, to name only a few.

For many people, reading a list of food additives is like trying to decipher a foreign language. Long-winded names of chemical compounds can cause concern and confusion.

Food additives, usually present at very low levels in foods, are introduced during processing to improve texture, enhance taste and/or appearance, maintain nutritional quality, or prevent the growth of bacteria and moulds. Regulated by the Food and Drug Regulations issued by the Food Directorate of Health Canada, food additives must pass through detailed and rigorous testing that assesses their effectiveness and safety. Even so, some scientists have voiced concerns that consuming large amounts of some approved additives may pose health risks and that more testing is needed.

Here's a quick guide to seven common foods additives: what they are used for, and whether they're safe or controversial (and should be given a pass).

Ascorbic acid (ascorbate)

Found in fruit drinks, canned fruit, cured meats, preserved fish and breakfast cereals, ascorbic acid – or vitamin C – is added to foods to boost vitamin content, preserve colour, prevent spoilage and/or maintain acidity.

Ascorbic acid is identical to vitamin C found naturally in fruits and vegetables. Sodium ascorbate, also safe, is a combination of ascorbic acid and sodium and is more soluble that ascorbic acid.

Benzoic acid (sodium benzoate)

Occurring naturally in many fruits and vegetables, benzoic acid is used to prevent the growth of mould, yeast and some bacteria in foods such as soft drinks, jams, fruit juice, pickles, ketchup and tomato paste. While safe for most people, benzoic acid may cause hives, asthma and eczema in sensitive individuals.

Cellulose (methyl cellulose):

Typically made from wood pulp, cellulose can be added to flavoured skim milk, salad dressing, cottage cheese, processed cheese, shredded cheese and ice cream to thicken and stabilize and/or prevent clumping and crystallization. Because it's an insoluble fibre, it passes though your digestive tract. It may even promote the growth of gut-friendly bacteria.

Caramel colour

Allowed as a colouring agent in colas (diet and sugar-sweetened), whole wheat bread, rye bread, ketchup, malt vinegar, soy sauce, jams and jellies, sherbet, wine vinegar, beer and some spirits, this artificial colouring is made by heating sugar together with ammonia compounds, acids or alkali.

When made with ammonia, caramel colouring contains two contaminants, called 2- and 4-methylimidazole, that have been linked to cancer in mice. The World Health Organization (WHO) considers 2- and 4-methylimidazole to be "possibly carcinogenic to humans" and California's Environmental Protection Agency has listed ammonia caramel colouring as a carcinogen.

You can't tell if the "caramel colour" stated on an ingredient list was processed with ammonia or not. If you're a regular cola drinker, consider avoiding it or cutting back. Baked goods, soy sauce, ketchup and other foods are considered less of a problem because the amounts consumed are small. If you're concerned about caramel, look for products free of caramel colour. The Center for Science in the Public Interest (CSPI), a consumer advocacy group with offices in Ottawa and Washington, recommends avoiding it.


Extracted from red seaweed using acids or alkali, carrageenan thickens and textures foods such as salad dressings, low-fat chocolate milk, evaporated milk, non-dairy beverages (e.g., almond, soy and coconut beverages), beer, calorie-reduced margarine and infant formulas.

When acid is used to separate carrageenan from seaweed, it causes the carrageenan to degrade. Degraded carrageenan (not the type added to foods) in very high doses has been linked to gut inflammation and colon cancer in animals. Yet, some experts contend that food-grade carrageenan contains some degraded carrageenan, which could harm the gut.

The FDA and WHO have concluded that food-grade (undegraded) carrageenan does not pose a cancer risk in people. In light of the controversy, the CSPI believes the additive needs more testing and advises caution.

Xanthan gum

Used to thicken and emulsify foods such as salad dressings, cottage cheese, cream cheese, sour cream, ice cream, whipped topping and infant formula, xanthan gum is made by fermenting corn sugar with a bacterium called Xanthomonas campestris. It's popular for gluten-free baking because of its binding properties. Xanthan gum is perfectly safe to consume.

BHT (butylated hydroxytoluene)

Permitted in chewing gum, dried breakfast cereals, parboiled rice, olive oil, citrus oils, margarine, shortening and potato chips, BHT acts as an antioxidant to prevent fats and oils in foods from going rancid.

While some studies have deemed BHT to be safe, others have found it to cause cancer in rodents. The U.S. Department of Health and Human Services considers the additive to be "reasonably anticipated to be a human carcinogen." The CSPI recommends avoiding it.

Leslie Beck, a registered dietitian, is based at the Medisys clinic in Toronto.