Tuesday, 17 March 2015

Caramel Colour, Soft Drinks and Cancer Risk

Caramel colour or colouring is a chemical that is added to some soft drinks to given them a rich brown colour. Some versions of the colour contain a chemical called 4-methylimidazol, or 4-MEI, which has been found to cause cancer in lab animals when a large dose is administered. A controversy has arisen about whether the chemical poses a risk to humans. According to the FDA (Food and Drug Administration), the chemical is safe in the normal amounts consumed by humans. However, a recent report by scientists at John Hopkins University claims that many people may be ingesting caramel colour on a daily basis and may be increasing their risk of cancer as a result.

Cola and root beer may contain caramel colour.
Photo by PDPics at pixabay.com
Although they are related products, caramel colour is not the same thing as caramel. The first product is used as a food colour, while the second is a sauce used in pudding, candies and chocolates.

Caramel sauce is a brown, gooey and (I think) delicious product. It's made by heating sugar to a high temperature very slowly. The sugar loses its water content and changes to a light brown colour. The sugar is said to have been "caramelized". Caramel is added to some candy bars. The production of toffee and dulce de leche also involves caramelization of sugar.

Like caramel, caramel colour or colouring is made by heating a carbohydrate. (Sugar is one type of carbohydrate.) It's a more extreme process than the caramelization used to make candies and desserts, however. An acid, alkali or salt is added to the carbohydrate as it's processed, producing a dark brown liquid.

Based on their studies, the John Hopkins researchers say that in the United States 44% to 58% of people over the age of 6 generally drink one can of soda a day. Assuming the soda contains caramel colour and that this colour contains 4-MEI, this means that the people are exposed to 4-methylimidazol on a daily basis.

It seems to me that the following questions must be answered before we can decide whether soft drinks are safe or dangerous (with respect to cancer).
  • Does the person's chosen brand of soft drink contain contain caramel colour?
  • If so, does the caramel colour contain 4-MEI?
  • How often must 4-MEI be consumed and in what quantity before it's dangerous to humans?

The FDA report and the John Hopkins report are both interesting to read. They may leave a person confused about the best plan of action. To me, it doesn't make sense to ingest a potentially dangerous chemical that has such an unimportant function as colouring a drink. We are exposed to many substances in the environment that may slightly increase our risk of cancer. It seems advisable to avoid as many of these substances as possible - including caramel colour - whenever we can. If I were a regular soda drinker I would make sure that my soft drinks either contained no caramel color or contained a form of the colour without 4-MEI.