Friday, January 18, 2013

The weekly dose: Is there a real harm to food dye?

{Once a week we examine the evidence pertaining to a health-related matter-- usually something that would be of interest to families with young children.  (However, the subject could be anything that piques my interest.) You should expect a thought out and concise summary of the issue along with several solid references-- there may or may not be a true conclusion.  Sometimes, “more research is needed”  really is the best answer that can be given.}

Several weeks ago I was browsing my Facebook feed and noticed someone posted an article about the dangers of food dyes, and how my friend was consequently going to return the fruit snacks they had just bought.  Mentally I filed this issue in the “non-scientific hippie” folder, but was curious as to why food dyes were being portrayed in such a bad light.  I mean, I didn’t imagine that they’d be nutritious, but I didn’t really expect them to be deleterious either.  After some digging, I was surprised to find that there is quite a history to this issue.

The question that I wish to answer: Do the risks associated with synthetic food dyes warrant the removal of foods containing these dyes from a family’s diet?

As background information, the FDA regulates all color additives (1), and has for some time.  In 1966 the FDA restricted the use of many color additives due to adverse health risks, and has continued to limit the allowed color additives since then (2).  Today, there are 9 synthetic dyes that are approved for use (2, 3). However, there is concern that these 9 approved dyes are also associated with adverse health risks.

The Center for Science in the Public Interest (CSPI) published a 58 page report in 2010 summarizing many of the risks associated with synthesized food dyes (3).  In this report, Kobylewski and Jacobson examined published studies pertaining to the carcinogenicty, genotoxicity (ability to cause mutations or damage chromosomes), and neurotoxicity of these 9 food dyes.  Although some of the studies they reviewed were imperfect and lacking in one way or another, I believe it is still highly concerning the amount of evidence that suggests food dyes are associated with serious health risks. Some of these adverse risks include, tumors in multiple locations, various cancers, and an allergic-like hypersensitivity (3).   After reading the report, I agree with the conclusion Kobylewski and Jacobson reached-- that synthesized food dyes do not belong in our food since they posses no nutritive value, and are likely detrimental to our health.

To examine what else had been published, I searched PubMed ( using the search terms “food dye*” which resulted in 254 hits.  Since most of the studies Kobylewski and Jacobson referenced were either animal studies or in vitro studies (Latin for, “in glass”, these are studies that typically look only at a cell or molecule, but not the entire organism) I was interested primarily if anyone had studied the affects of food dye in a human population.  After applying a species filter of “humans” to my search, I had 61 hits-- a manageable number to look through.  After reading the titles, I narrowed the studies down to 26 articles that appeared relevant to my question.  The publication dates ranged from September, 1974 to July, 2012; apparently the safety of synthetic food dyes is not a new area of research.  Admittedly, I didn’t read through all 26 articles, but most of them were studies related to treating ADHD, and it appeared as if they were all ending up with similar conclusions.  In summary, ADHD is complicated, and we should not expect changing a child’s diet to act as a panacea, but, the elimination of artificial food dyes likely does reduce ADHD symptoms.

In 1970 Dr. Benjamin Feingold found that when artificial food additives and dyes were eliminated from the diets of hyperactive children, the symptoms of hyperactivity were reduced.  However, follow up studies during the next 20 years were less than convincing.  Because of this, interest in the effects of food additives on hyperactive children waned.  Recently though, there has been more research and public interest regarding this association.  Because of these circumstances, in 2009 the British government requested that food manufacturers remove most artificial food dyes from their products (4).  It is sadly ironic that food companies that produce food for both Britain and the US use natural or no colorings there, but continue to use artificial dyes in America (3).

In one study, the authors point out that even though controlled studies usually suggest the elimination of artificial food dyes to reduce ADHD symptoms, this is really a recommendation that should apply to the diets of the entire pediatric population (5).  Konikowska et al., (6) state that although the cause of ADHD is unknown, many studies show that nutrition is a large factor in the development of symptoms.  Although I have not read anything that suggests that artificial food dyes cause ADHD, this study again points out that many studies have shown a positive impact of the elimination of food products containing synthetic food additives on the behavior of children with ADHD (6).

So, what does this mean for my family?  For us, this means that I now consciously avoid buying products that contain synthetic food dyes, even if this means paying a little bit more for a dye-free alternative.  Previously when I read food labels I’d generally ignore the food dye information.  We don’t eat a lot of processed foods, so I didn’t anticipate this being difficult.  However, we do eat a decent amount of whole-grain breakfast cereal, and I discovered that Life Cereal has several food dyes in it (although Kix and Rice Krispies do not).  This is sad news since Life often goes on good sales and my husband enjoys it.   That said, I don’t believe food dye will single handedly give us cancer or otherwise kill us, so we intend to be level headed and still enjoy food when others offered to us-- even if it does contain food dyes. 

(1) FDA. For Industry: Color Additives. 2011. Accessed 1/16/13.
(2) FDA. For Industry: Color Additives Status List.  2009 (updated 2011).  Accessed 1/9/13. 
(3) Kobylewski, S, and Jacobson, MF. Food Dyes, A Rainbow of Risks.  2010. Center for Science in the Public Interest.  Accessed 1/9/13.
(4) Kanarek, RB.  Artificial food dyes and attention deficit hyperactivity disorder. Nutr Rev. 2011 Jul;69(7):385-91. doi: 10.1111/j.1753-4887.2011.00385.x. Epub 2011 Jun 30.  Accessed 1/17/2013.
(5) Hurt, EA, Arnold, LE, and Lofthouse, N. Dietary and nutritional treatments for attention-deficit/hyperactivity disorder: current research support and recommendations for practitioners.  Curr Psychiatry Rep. 2011 Oct;13(5):323-32. doi: 10.1007/s11920-011-0217-z. Accessed 1/17/2013.
(6) Konikowska, K, Regulska-Ilow B, and Rózańska D. The influence of components of diet on the symptoms of ADHD in children. Rocz Panstw Zakl Hig. 2012;63(2):127-34.  Accessed 1/17/2013.


Emily said...

Do you think artificial dyes are only problematic in food, or are you also concerned with them in toothpaste, cosmetics, shampoos, etc.?

Rebecca said...

That's a really interesting question, and I really haven't thought much about that aspect of artificial dyes. To properly address the issue of dyes in other products, I would have to address a different question (perhaps another post?).

But, after reading the information in the CSPI report (#3) about the toxicology of synthetic dyes, I'm certainly more inclined to think all applications might be problematic. I'd think putting it on skin or brushing your teeth with it would carry significantly fewer risks-- especially since the major risks seem to be with increasing hyperactivity, but that's really just my best guess.

An interesting side note, to me at least, is that all dyes are not approved for all applications (see ref. 2), and there are only a few that are approved for the area around the eye.