9 things parents should know about food dyes

Colourful food is appetizing; the brighter it is, the louder it shouts "Eat me!" But not all food colours are friendly—here's what you should know about artificial food dyes: where they hide, how they affect your kids' (and your own) health and how to limit them.

1. Food dyes are for looks only. Artificial food colours (AFCs) do not enhance the nutritional value of food and drinks. They are often added to foods that are artificially flavoured to appear the colour you would expect from a natural flavour (such as the vivid orange colour of an orange-flavoured drink), to intensify the colour of natural foods, and even to make foods look more natural (for instance, adding yellow to baked goods to make them look like they contain eggs).

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2. Food dyes come from an unexpected source. Many people don't know that AFCs are often derived from petroleum by-products or coal tar.

3. They hide in many foods kids love. A 2013 study from researchers at Purdue University, in Indiana, found that one of the main ways kids are exposed to AFCs in their diet is through drinks—fruit juices and punches, soft drinks, sports and energy drinks—mainly because kids consume larger volumes of beverages compared to other foods with AFCs. Researchers at Purdue also found the most dramatic increase in the use of food dye throughout the years is in high-sugar breakfast cereals and candy. Other common places AFCs hide include: boxed dinner mixes, ice cream, snack foods, cakes, icings, cookies, pudding, candy and Popsicles.

4. Food dyes can be in the non-foods your kids consume, too. Many children’s medications (both over-the-counter and prescription), vitamins, toothpastes and mouthwashes also contain AFCs. Some brands now offer dye-free options.

5. Artificial colouring is often found in “healthy” foods. Surprise! Your morning yogurt may contain AFCs, according to Purdue researchers. Same goes for certain cereal bars and baked goods. Muffins and cookies may have added AFCs to make them yellow to suggest the presence of eggs or brown to make them appear more wholesome. Cereals and baking mixes with fruit—a blueberry muffin mix, for example—may contain food dye to make the fruit bits appear more vibrant. (See below for a complete—often surprising!—list of some foods that commonly contain AFCs.)

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6. They aren’t always obvious on food labels. Health Canada has proposed more transparent labelling for allergens including AFCs in foods, which currently can appear on ingredient lists by their proper name (caramel), a colour and number (Red#40) or simply with the non-specific “colour.” Working ahead of the curve, the European Union ruled in 2010 to not only call out specific AFCs on food labels, but also to include the warning “May have adverse effect on activity and attention in children.” This has seen the number of products containing AFCs as well as consumption of them decrease in the EU.

7. Artificial food dyes may be linked to behavioural issues in some kids. There is some research to suggest that AFCs might have an impact on the behaviour of a small group of kids with hyperactivity or a diagnosis of ADHD. While some research has shown that AFCs may also increase hyperactivity in kids without ADHD, the same conclusions can not necessarily be extended to all children (those studies observed kids after drinking a beverage with both AFCs as well as a preservative). Allergic reactions, irritability and sleep disturbances have also been reported in some kids. While the research on the relationship between AFCs and behaviour in kids continues, the AFCs you'll find in food today are considered safe for the general population by both Health Canada and the U.S. Food and Drug Administration.

8. It’s getting easier to avoid AFCs. Some food companies have responded to public pressure by creating naturally dyed options—you’ll find snack crackers and macaroni-and-cheese mixes coloured with vegetable extracts, and candy imbued with real fruit and vegetable dyes, for example.

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9. There may be other good reasons to avoid foods with artificial dyes. Avoiding foods that commonly contain AFCs generally means eating less processed, high-in-sugar foods, so limiting those is already a good idea. Same goes for beverages like fruit and sport drinks—they're often high in AFCs and sugars and should be curbed in favour of water. A caution to parents who may wish to follow a more natural, dye-free diet or simply decrease the amount of AFCs their kids are exposed to: food dyes are so prevalent in the foods kids eat and drink, it's best to discuss with your child's doctor or a registered dietitian before making any significant changes to their diet.

Common foods children consume that may contain AFCs Beverages Boxed macaroni and cheese Cakes Candies Cookies Cracker-and-cheese snacks Cupcakes Doughnuts Gelatin mixes Icings Popsicles Ready-to-eat cereals Slushies

“Healthy” and other surprising foods that may contain AFCs Baked goods BBQ sauce and other sauces Blueberry muffin mixes Bread Cake mixes Cereal bars Cheese Cherry pie filling Chicken-coating mixes Children’s medications Healthier-appearing whole-grain cereals with fruit Horseradish Ice cream Ice cream cones Imitation-chocolate sprinkles Marmalade Microwave popcorn Mouthwashes Mustard Pasta mixes Pickles Potato-dish mixes Rice mixes Salad dressings Toothpastes Vitamins Yogurt granola bars Yogurts

Joelene Huber is a pediatrician and assistant professor of paediatrics at the University of Toronto and works at the Hospital for Sick Children, specializing in development and autism spectrum disorders. She is a regular on television news programs and mom to two small children. Follow her on Twitter at @DrJoeleneHuber.