Thursday, March 17, 2011

Elimination Diets for ADHD Not Ready for Primetime

The news has been full of reports of the INCA study, including the following conclusion on National Public Radio from the lead author, Lidy Pelsser, MSc: “64 percent of children diagnosed with ADHD are actually experiencing a hypersensitivity to food.” CHADD experts have looked at the study published in The Lancet. Without a great deal more research that supports the findings of this study, we would urge people to slow down and not jump to trying an elimination diet.

The families in the study were either put on a rigorous and closely supervised elimination diet or assigned to a control group that received instructions for a healthy diet. An alternative explanation for the results could easily be that the children in the experimental group responded well to a highly structured environment and lots of attention—both necessary for an elimination diet—and not the diet itself. Another explanation is the all-powerful placebo effect.

While this was a randomized study, the participants all knew which group they were in. This lack of blind experimental and control groups is a major research design flaw. The placebo effect is usually controlled by making sure all participants are blind to the intervention they are receiving. For instance, an experimental group might get the elimination diet and the control group might get a bogus elimination diet which eliminates only foods unlikely to make a difference. Then the children in both groups would receive the same amounts of structure and adult involvement. That did not happen in this study. Conclusions about hypersensitivity to food and ADHD cannot be made on the face of this single study, and certainly not when the groups were aware of the interventions.

Years of research on diet and ADHD have concluded that a very small percentage of children with ADHD who also have food hypersensitivities may do well with a controlled diet. So if you know or suspect your child has food hypersensitivities, then you may want to try an elimination diet with good medical supervision. But for the vast majority of people with ADHD, there is not yet evidence that this will make a difference.

Ruth Hughes, PhD
CHADD Interim CEO

12 comments:

Tabitha Boler said...

Perhaps you would benefit from a little more research with individuals who have been on an elimination diet for decades. The Feingold program (in its simplest sense) is just that, an elimination diet. It is not new in any way. What I don't understand, is why anyone would think that coal tar (FD&C colors) and petroleum based preservatives in food would NOT do us harm? They are not edible items and most people consume large quantities of them every day. Why would numerous reactions to these items surprise anyone?

Look up Azodicarbonamide and see how comfortable you are with consuming it. Now go to a regular grocery store and look for a loaf of bread without it. Its not a matter of just eliminating items that are causing allergic reactions, its about removing items from food that aren't edible. Isn't that just logic?

Tricia said...

I grew up on an elimination diet, Feingold in the 70's and it does work and has continued to work for many, many people. I was raised with medications and without any special accommodations in regards to my education. I also graduated from college at the top of my class. Some of the things added to food have been proven unsafe, so much so that the EU has banned the use of several of them. Also the additives that companies still insist on using must carry a warning label, similar to those we put on tobacco and alcohol.

Tricia said...

I want to clarifly I was raised WITHOUT medications!

Eic said...

The view of not trying an elimination diet is myopic at best, potentially irresponsible at worst. True, the study was initially open but then it was a crossover study where the successful group was then challenged with foods and found some reduction of benefits. Considering the risk of diet modification as compared to drug use, I would be remiss in my role as a physician (and parent) to not include a treatment modality with such low risk potential. Even if using a drug treatment, the potential to provide a reduced drug dose and thus reduce adverse effect potential warrants a serious trial of dietary modification. Considering the adulteration of our current food supply and the mysterious and varied nature and presentation of this disease, it is only prudent to consider and include low risk treatment modalities if they might show benefit. There is no one answer for all. I highly recommend at least a serious trial with diet. What if it works and no medication is needed for that individual? That child wins! And if it doesn’t work? They are right back where they started.

Meg said...

I and my children are part of that very small percentage of people for whom food hypersensitivities cause sometimes severe ADHD-type behavior. It is frustrating to continually read that this is an invalid or worthless avenue to explore. Critique the study all you want, it does have flaws, but please don't denegrate a potential treatment method that is not only effective, but drug free and completely without negative side effects. I suspect the number of people who share our sensitivities are more than a very small percentage, but even if it isn't, it is a real reaction and a real problem, and should be given real validity.

Lynne said...

If anyone would like to join the Feingold Association and give the Feingold diet a try, the members of our group are very helpful in implementing the diet. We love to help members figure out what additional foods or chemicals their children may be allergic to, and to help them figure out the best approaches to eliminating their allergies, if that is what they want to do. www.feingold.org

Naomi (Ontario Canada) said...

I am a Feingold (FG) user and have found the diet very helpful in a number of health conditions which were not controlled by medicine. I am on meds for ADD but am hoping at some point to slowly lower them so that I can see if FG will help the ADD too. I think that the simplest intervention and the first line of defense against ADD (inattentive or hyperactive or a cobo) should be diet. It only takes 6 weeks in general to see some improvements..some less time soe longer. And for some a small amount of meds are required with the FG program. Wouldn't you rather find out your child was helped out by changes in the way you eat then by putting them on powerful medication, having to adjust and readjust the dose or try another medication. Or is it easier just to pick a pill out of a bottle rather then cook healthy nutritious food for your family. I was I had had FG when I started on my medication journey. I truly believe I would not be on the meds I am today.

Naomi-Ontario Canada

CAS said...

Elimination diets are most difficult to maintain over time, especially a very restricted diet like the one in this study. And balanced nutrition is difficult to achieve with a severely restricted diet that contains few foods that a child may like. I'm not opposed to dietary manipulation that has good research backing it up. But before I recommend a very restrictive elimination diet, I want to have double blinded randomized control trials with adequate numbers to show both efficacy and safety.

Melanie said...

What's so great about an elimination diet is that you can do it yourself, at home, with very little expense. It's certainly less disruptive to family life than trying medication or various therapies and it works for most children whose parents implement it properly. Anyone in doubt should read the stories at www.feingold.org.
It's "just" anecdotal evidence, but every child is its own little anecdote...wouldn't it be nice if your story had a happy ending? Ours did.

indoor bike trainer said...

Healthy diets are almost performed by those who want to lose weights. It is much safer than taking pills. Veggies are on of the example of foods that being eaten in healthy diet.

Melanie said...

Poster writes:

"But before I recommend a very restrictive elimination diet, I want to have double blinded randomized control trials with adequate numbers to show both efficacy and safety."

Fair enough. In the case of the article, it's possible that the diet really was very restrictive. The Feingold diet is not particularly restrictive....we thought it would be much tougher than it actually is. And, unlike medications with long lists of side effects, this diet has NO negative effects to it. Sure, your child may have to do without some favourite foods for a while, but you may in your journey find that those favourite foods were causing the problem. Alcoholics crave alcohol, many kids with gluten and casein digestion problems crave those foods, and some kids with ADHD crave the foods that irritate their central nervous system. But rather than giving them a pharmaceutical that restrict their brain, I'd rather do a diet that restrict their reaction to chemicals that are unhealthy for them.

Cheranne said...

How would you design a study in which one does not know what he/she is eating? Just because this is difficult, does not mean that there is NO benefit from such a study, despite inherent flaws. Short of eating mush blindfolded and with noseclips on for six weeks,which has sets up more serious study flaws, I don't know how the study could be designed differently. So, the study should just be repeated a few times. Also, on another note, if one were to try such a diet, where would one begin