Study links food additives to behavioural problems in children

Not sure if this thread belongs here, but let’s give it a try.

I realise this is just a write-up in the popular press, but it appears to be describing a double-blind trial, commissioned by the Food Standards Agency, in which a significant link was observed between the consumption of food additives (mainly artificial colourings) by children, and adverse behaviour.

OK, it’s not a very large-scale study - clearly there’s more to do, but it does seem to tentatively confirm the experience of many parents, which has hitherto often been dismissed as worthless anecdote or wishful thinking.

Does anyone here have access to The Lancet, and feel like fleshing it out with a bit more solid data, or wish to point out possible flaws in the study?

I can’t find the paper online or in our library database, so it’s probably in the newest edition.

The news coverage I’ve seen gives short shrift to those questioning the significance of the study. Things to look for in the article include whether it was indeed a double blind study, what the signs and symptoms displayed were, whether they correlate with signs and symptoms of ADHD, whether they were long-term effects in these kids, whether earlier studies that failed to show these effects were limited or poorly designed (or if this description fits the current study).

And so on.

I don’t think there is any question that food reactions can be severe in many people. This is becoming well understood in the case of migraines, whereas when I suffered from them as a kid this wasn’t well understood at all.

My mother, driven to desperation, put me on a modified Feingold diet in an attempt to cut down on the migraines. This worked, though for different reasons than the ADD stuff. The Feingold diet removes, coincidentally, nearly all migraine triggers.

After a while we were able to determine what those triggers were, and lessen the diet restrictions. This was well before most doctors were well versed in this area - though all of them now know about it. Fortunately, we had a pediatrician who didn’t discourage my mom in this area, and I think he reported her successes to the parents of his other pediatric migraine patients.

I don’t know if there is anything behind the link behind food additives and ADD, but I have never been inclined to dismiss this, given my own reaction to certain foods.

From the print Globe and Mail:

The study consisted of 153 pre-school children and 144 children who were between 8 and 9 years old.

They were given either ordinary fruit juice or one of two drinks identical in looks and taste, one of which contained varying levels of artificial coloring and a set level of sodium benzoate. One batch with the additives contained the average daily intake of food coloring for their age groups, the other had elevated levels equivalent to two 56-gram bags of sweets for the three-year olds and four bags of sweets for the older children.

None of the children had extreme hyperactivity or attention deficit disorders prior to the study, and during the six-week study none of them consumed other foods containing sodium benzoate.

Investigators reported that the spiked drink containing higher levels of food coloring had a “significant adverse effect” on the three year olds, while both mixes increased hyperactivity in the 8 or 9 year olds.

Across the board, the children who consumed the elevated mix moved about 10% closer to an internationally accepted definition of hyperactivity.

The quote from Jim Stevenson, a professor of psychology at Southhampton was , “We now have clear evidence that mixtures of certain food colors and benzoate preservatives can adversely affect the behaviour of children”.

Bill Mahoney, associate professor of pediatrics at McMaster University said, after reviewing the study, “This isn’t taking very placid children and turning them into kids who are running all over the place.” “The effects, in general, are very small.”

Philip Shaw, a clinical fellow at the National Institute of Mental Health in Bethesda, MD, said the study was probably the most comprehensive of it’s kind, but questioned whether it would have the sort of far reaching implications that it’s researchers imagined.

So, OK, the size of the study was small, but not on the order of a dozen kids in a single pre-school class.

I’m impressed by the fact that there was apparently a dosage effect in that the higher levels of preservatives had an effect in three-year olds that the lower dosage did not.

They don’t mention whether it was double blind. It seems like an obvious thing to do, and I’d be surprised if something could get peer reviewed without it, but it didn’t make the Globe and Mail .

The 10% closer to an “internationally approved definition of hyperactivity” could use some fleshing out. I’d like some details on what that definition is.

There probably is an effect, but it’s small and selective. I’m figuring it’s like salt sensitivity in hypertension. Only around 10% of the people are salt sensitives in whom sodium worsens hypertension, but if you’ve got hypertension, it’s a good idea to restrict salt, because you’re probably one of them.

Same thing here. If you have a non hyperactive child, don’t worry about the sodium benzoate, if you’ve got a hyperactive child, you might be able to ameliorate the problem with a restricted diet.

The Daily Mail (OK, not the world’s most reliable source) explicitly states that it was double-blind

-Previous studies have been (rightly) criticised for failing in this respect.

So, artificial ingredients produce adverse effects. Color me surprised.

What coloring should we use?

Isn’t this really old news? I mean I am 38, and I remember stories when I was at school concerning “E-numbers” and hyperactivity. I just assumed this was already widely accepted.


It was, at least by parents, in the '80s and early '90s. Then we were told that there was “no evidence” of harm and in fact at least one previously banned colorant (Red #5, I think, previously suspected of causing cancer, was it?) was put back on the market. So we spent a decade buying neon glowing yogurt in tubes and “fruit drinks” which blind small dogs at 20 paces. Most docs would sigh and say that “It probably won’t make any difference, but go ahead” if a parent wanted to try and change her kid’s diet instead of put him on Ritalin. Aaaaaand, here we are now.

I agree this is far from conclusive, but I suspect** Bill Door**'s saltlike hypothesis is going to be borne out eventually. For most kids, it probably doesn’t matter. For some kids, it will. So if my kid were to be diagnosed with ADHD or even ADD, I’d start yanking artificial dyes and preservatives (which, actually, we hardly eat anyway since they tend to be in highly processed foods) before putting him on meds.

That seems to make sense. I guess in between leaving school and having a kids, which fortunately was a long time period, I just missed out on the retractions.

My son is 7, and eats some processed food but not a lot. The behavior changes I see come from something much more simple - sugar. Damn that white powder hops him up…

[anecdote hijack]

Man, just orange juice is enough to make the toddlers go insane! I have three of them at a time, it’s really noticeable!

Two days ago, I pulled up in my car at the same time as the mom of one of my charges pulled up to drop him off. I opened his door to find him in his car seat, powdered sugar donut in one hand, another in his chipmunk cheeks, and a bottle of that barrel-shaped sugar water in the other. :eek: I almost told her no way, I’m not taking him that hopped up on sugar! Almost. Too bad I need the money. The really weird thing is that she’s the “He’s only eating organic cereal and organic milk and organic produce while he’s at your place, right?” mom. Grr.

“Across the board, the children who consumed the elevated mix moved about 10% closer to an internationally accepted definition of hyperactivity.”

I’m not sure how they measured this, but if it actually translates to a statistically significant effect, it’s probably by the skin of its teeth. I see from a prevous post that this does appear to have been a double-blind trial, but whether it’s enough to be definitive evidence that food additives are important in causing hyperactivity (given the shaky evidence to date and the multifactorial nature of the disorder) is questionable. From a recent article in a pediatrics journal:

“The possible role of foods or additives in causing behavioral disorders in children, particularly ADHD, has been a controversial subject both among health care providers and the public. However, a critical review of the literature provides very limited support for such a relationship. On encountering such cases, the healthcare professional should first establish an accurate diagnosis of the suspected “abnormal” behavior based on specific standard criteria. It is important to counsel the family regarding the standard of care practice and about the limited evidence of a role of foods and additives in causing behavior problems. If parents strongly suspect a specific dietary item, a trial of elimination may be warranted. If the child’s behavior shows definite improvement, a challenge in a double-blind, placebo-controlled fashion under the supervision of an experienced physician would be necessary to verify the relationship.”

Wonder if the trial published in Lancet took this step (with kids displaying supposed hyperactive signs/symptoms, taking them off the additive-containing drinks, to see if their behavior returned to “normal”?

Once more, slowly, for the addled: So the problem with sugary candy isn’t the sugar, but the artificial color? It’s used that consistently, such that they can say “this is the level associated with a bag of sweets”?

That might explain why mine can handle chocolate, but not Easter candy. I thought it was the interaction between the high level of fat in chocolate and serotonin levels.

My girlfriends swear that artificial coloring in medicine has the same effect on some of their children.

By any chance, are these the same friends who told you that a chiropractor relieved their kids’ asthma?


Nope, different friends. I still think the chiropractor/asthma thing was goofy as all hell — but my Ped’s approach to asthma (meds! meds! more meds!) wasn’t much better. Instead I used the advice in Jeffrey May’s book My House is Killing Me and altered our environment (put mattresses and pillows in bags, change furnace filters frequently, nix the stuffed animals, wash bedding frequently and on hot, buy a good HEPA vacuum cleaner and use frequently, no carpeting or curtains in the bedrooms, get rid of the long-haired cat, take the humidifier unit off the HVAC). Now she only needs steroids and bronchodilators when she’s got a cold (of course I still have them on hand); the rest of the time she’s fine.

I’ll need to read the study, but it sounds pretty flawed on cursory glance. There are artificial perservatives and coloring in all sorts of foods from hamburgers and french fries to Skittles and Snicker bars. This leads to me to two questions:

  1. In the control group, how did the investigators prevent children from consuming foods with no food colors or preservatives. What was the typical daily meals (breakfast, lunch, and dinner) for these children?

  2. Where’s the biology? Does administration of artificial colorings and preservatives exhibit the same activity on mice? If it does, what are the neurobiological underpinnings.

Now, I am not a chemist, so please correct me, but benzoic acid looks to be pretty polar with a partial positive charge on the hydroxyl’s proton. There is no way that molecule will get through the blood-brain barrier and exert psychotropic effects this study is claiming.

  • Honesty

These things wouldn’t need to. Sometimes they can cause a hormonal or other biochemical change elsewhere in the body that manifest symptomatically as a behavioral shift.

Mind you, I’m not saying definitively that this is happening, merely pointing out that saying the blood-brain barrier can’t be crossed here doesn’t definitively answer this question. Physiology is alot more complex than that, as I’m sure you’ll allow.

Here’s a woman who has a patent on a process using benzoic acid (among other things) as a co-surfactant to facilitate the transfer of drugs across the mucosa and blood-brain barrier. She probably is a chemist.

You’re right, benzoic acid is polar, I don’t know what it’s logD value is off the top of my head, but a pKa of 4.2 indicates that it will be mostly ionised at physiological pH (ca. 7.4). So a poor candidate for passive diffusion into the brain.

Many polar molecules are delivered into the brain by active transport, though, as I am sure you know (amino acids, neurotransmitters etc). Monocarboxylic acid transport systems exist throughout the body, so it is quite possible that benzoate could penetrate the brain by this mechanism. Saying that there is ‘no way that molecule will get through the blood-brain barrier’ is a bit over the top.