Talk given to psychiatrists group We are all familiar with people feeling like picking a fight, dancing on the table, or crying into a drink, as being due to alcohol. What I propose is that there is an equally wide range of mood changes which result from a different group of substances in food – in a particular, that is, susceptible, subgroup of the population. Furthermore, just as it is possible for alcohol use to interact with depression or any other psychiatric disorder, it is also possible for food sensitivity to interact with these disorders.
There is a gradually accumulating body of evidence that some factors in food can affect mood.
I will provide key papers from the literature and describe the phenomenon as it occurs in my dietetic practice, in which I specialise in the investigation of suspected food sensitivity.
Let me give you a description of my food sensitive patients. They are in families with particular bunches of symptoms. These include ADHD, ASD, some allergic (atopic) symptoms, with another group of symptoms. Allergic symptoms include familiar symptoms such as eczema, hay fever, sinusitis, rashes, diarrhoea, and asthma. The other group of symptoms are some that we do not expect to usually see associated with allergy. They include headache, migraine, tummy aches, irritable bowel syndrome, mouth ulcers, sleep problems including nightmares, and car sickness. These types of symptoms often occur in families susceptible to food-sensitivity.
Where did the idea that diet could affect behaviour originate?
The idea that diet can affect behaviour has been around for hundreds of years, but it was only relatively recently that such wisdom was subjected to scientific study. Early in this century there were reports of behavioural, or neuropathic, changes due to food allergy [Shannon Duke and Rowe]. Schneider in 1945 implicated allergy in childhood hyperkinesis. In the 1950’s, Speer included behaviour changes in children at the hypoactive end of the spectrum, in an allergic tension-fatigue syndrome. In 1970, Kittler reported improvement in Minimal Brain Dysfunction in children when allergens such as milk and chocolate were excluded.
The work that caused the most controversy was that of Feingold, who reported in 1973 that when his patients were placed on a low-additive, low-salicylate diet, the parents reported that they “became docile, better adjusted to the home environment …”. He went on to hypothesise that additives and salicylates caused hyperactivity. He also reported that diet reduced aggression.
The early research, up until 1985, refuted his hypothesis. However, later research, with improved methodologies, showed that there was a susceptible group of patients who did react. The detail of this research is presented in my 1997 review paper in the Australian Journal of Paediatrics and Child Health.
A report on adverse reactions to additives by Lessof in 1987 in the Journal of the Royal College of Physicians of London cautioned about the possibility of food phobia occurring. Lessof’s position was that individuals could develop phobias about certain foods, which may account for perceived adverse reactions. Certainly, psychiatrists deal with phobias regularly. However, in diet therapy I rarely see them. In fact, my patients are usually keen to try reintroducing suspect foods as much as possible, to see what they can tolerate. Where caution should be highlighted, I believe, and this is still rare, is in anorexics using suspected food sensitivity as a reason for food exclusion.
Why is mood worthy of being singled out for attention?
Mood was not singled out for attention initially. There are different strands to the research – that on ADHD, that on allergy and some on depression.
Research on allergy.
Those researching allergy reported changes in physical allergic symptoms. Where irritability was associated and it resolved, its resolution was assumed to have been due to the mitigation of the distress of the physical symptoms. The direct question of whether allergic exposure can provoke psychological symptoms in adults was addressed in a double blind study of sublingually administered allergenic extracts by King (1981). He notes that one usual explanation of psychological symptoms is that such reactions are psychosomatic, the second is that they are an effect of the physical symptoms, and the third, confirmed in his study, is that allergic exposure may be directly responsible for both psychological and physical symptoms. In fact, people can have symptoms related to mood, without, or in addition to, physical allergic symptoms.
- Research on ADHD
When early workers researched Feingold’s hypothesis from 1975 to 1985, hyperactivity was emphasised. Later research groups developed their work over time, researching a variety of behavioural and physical symptoms, as well as a broader view of the diet. Mood as a separate factor was first reported by Rowe of Melbourne in 1988. As Rowe and Rowe did not feel that the rating scales used for medication were as applicable to diet they developed the Rowe Behavioural Rating Scale [The RBRI] for diet research. They emphasised irritability, restlessness, settling and sleep problems as part of symptoms associated with additive colour challenges.
Kaplan’s team in Canada  used the Conners scale and added extra issues noted by parents. These included whininess, sleep and physical symptoms. They reported in 1989 that a decrease in night awakenings correlated with a decrease in ADHD behaviours on diet, but that physical symptoms did not, showing that difficult behaviour did not correlate with physical discomfort. On the other hand, Bock and Atkins  did report irritability in children in whom abdominal and cutaneous reactions developed. They had selected atopic subjects and had not used any separate behavioural rating scales.
In my early research of 1978, I reported that symptoms of anxiety and tearfulness in the presenting ADHD child, and in siblings, as well as aggression and poor socialisation, improved in addition to hyperactivity. In the follow up study of five hundred families  I, like others, reported that diet changed other factors as well as hyperactivity. I had categorised areas of improvement as; behaviour, learning, activity, social [having few friends, not being invited to birthday parties], sleep problems and physical symptoms. Rather than the “all or nothing” reaction described by Feingold, I found that diet was, “aggravating the underlying predisposition in susceptible children”.
My most detailed study, following up 120 children, was in the early 90’s. I used the RBRI, and found that the symptoms most improved on the diet were irritable, touchy, cranky, and reported that these children were hyper-reactive as much as hyperactive.
The following is an overview of the types of mood-based reactions that, over the years of my research, parents have described to me personally, and coded on questionnaires such as the RBRI. In food-sensitive children, diet has had a significant effect on all these symptoms.
Many children are reported as impatient, even more are irritable, touchy or cranky. Parents often say, “living with him is like walking on eggshells, one minute he’s okay, and the next his mood has changed completely!” Many are described as having a chip on their shoulder – sometimes a log! The questionnaire does not include the word angry, but children are often comfortable with using it. When asked how they feel on the diet, some children will say, “I don’t feel angry any more”. I have also heard several variations on a teenager’s clear statement that, “whenever I have red cordial I feel angry and just want to be by myself!” “He’s so agro”, even “cruel” are words used when coding aggression. I have discovered that when parents say their child goes “hypo” after a diet reaction, it is a mixture of hyperactive and aggressive!
Most patients are reported as excitable and this does not change with diet. However, the diet responders are reported to “come down faster” after any stimulus.
“Arguing about everything!” is a frequent comment about children over the age of seven and getting past the tantrum stage. Sometimes parents comment that, “he acts as if he wants to pick a fight”. Parents will unhesitatingly pick the extreme end of the scale when responding to such questions, and sometimes even ask if they can code, “off the page”!
When we come to the question on being happy the parents often stop to think for some time. They comment that the child is not really unhappy. They recognise that it is unusual for them to be so emphatic about how irritable the child is, and yet they would not code him or her as unhappy. However, a subgroup are described as unhappy or ‘cries often’. In a very small number, “I want to kill myself” was said often before diet and parents report it is said no longer in the diet responders.
Many do relate well to others, some do except at home, and even those who relate well may also be exasperating! Parents will say, “I love him but sometimes I could murder him!”
Easily frustrated is often noted, as is difficult to reason with. Parents generally use phrases like “off with the fairies”, or, “on another planet”, and they might comment he is “off his face” when having a bad reaction.
Aimlessness is connected to being bored, with the message from the child being that more interesting stimulus is desired. It may also reflect the level of irritability.
Preschoolers are reported to have frequent tantrums – “they never grew out of the terrible two’s!” They do decrease in the diet responders. Parents often say, “Joan, he runs just as fast, but I can get through to him now, and he is easier to live with”.
To return to other work on ADHD being published by the 1990’s:
Egger and Carter and their London team reported in 1991 that, “symptoms showing change are not the attention deficit that is considered the core of the ADHD but rather irritability” and that “children had become more manageable and more amenable to reasoning rather than less active or better able to concentrate”. This sounds rather like Feingold’s initial report, doesn’t it? In hindsight it would have been better if he had not emphasised hyperactivity as the key symptom. In a double blind study in Melbourne in 1994, Rowe reported that behavioural changes in irritability, restlessness and sleep disturbance are associated with the ingestion of tartrazine, that is artificial colour, in some children.
- Research on depression.
The third strand to the research was not related to ADHD, but to atopic [having allergic symptoms] families. A child psychiatrist who visited Queensland in 1999, Mariannne Wamboldt, has researched and published on the role of atopy in depression. She reports that there is a shared genetic risk for atopic and depressive symptoms.
This is interesting particularly because my research has indicated that there is a correlation between those coming from atopic families, and those who are likely to be food-sensitive. Wambodlt has completed the chain of thought suggested by the above research. By linking atopy and depression, we can see that atopic symptoms are a common factor that links mood and diet. Indeed, for many years earlier I had been asking my patients to fill out a “family sensitivity history” of atopic symptoms and suspect causes. It is not unusual for depression to be mentioned as a family problem.
How does mood come up during the diet therapy process?
In my work I am aware that I teach, particularly children, to be aware of and monitor their mood. Diet therapy for suspected food sensitivity in children begins by running a trial individual elimination diet, “to see if the child can handle himself better”. After the four-week trial, various categories of foods are reintroduced as challenges to see what changes. I call this “being a diet detective”. I am happy for children to prove they can handle themselves rather than having to stop eating the gradually increasing challenge foods. I am happy to teach children that if they feel cranky, but don’t get cranky, then they can still have the food [providing their sleep, physical symptoms and ADHD symptoms are also not returning]. I often tell the story of the bright early teen who said, “you mean ‘fake it?”. Big brother could manage that, but little brother could not. He insisted he was not reacting. He said things like, “it was big brother’s fault, he started it”, “the teacher is always mean to me!”, and, “you are always asking me to do more than my brother”. I use this in what I call “the Three-Pain Rule”. If in the space of a few hours, the child complains that three people, such as the teacher, another child and his mother, are “a pain”, when none were the week before, then he or she has to stop the trial food, and “maybe trial the food again next year when he or she may feel less touchy. An adult expressed the level of touchiness well by saying that before diet, and after challenges she, “not only felt annoyed with people, but felt she had good reason!” In saying this I am reminded that it is the improvements in this mood component, and even more important, the behaviours resulting from the touchy mood, that are particularly important to the parents.
Many parents report children being very anxious eg about having work ready for school, and adults report waking at night with feelings of a “panic attack”, with other symptoms when they have reacted to test foods. Adults with IBS often report that in addition to decreases in gut pain they feel calmer, less anxious, less “inward directed” on the diet.
As my patient group becomes broader, different groups with mood effects have emerged. In those who respond to diet, these problem areas all decrease. They may include:-
1 Happy high and silly – likeable, flighty, distractible, often talkative children.
2 Touchy people – Outward directed. If all is not well it is because someone else “started it!”, “It is all their fault”, “They are always picking on me”
3 Supersensitive folk – inward directed. They are more likely to say, “I’m no good, I’ll never have any friends, I’ll never be able to do this, I’m not good looking” or I worry about everything”.
4 Adults who report feeling calmer and with less mood changes on the diet.
If we look at all of these groups we have a fair representation of the general population. It is possible that the diet has a general effect on mood (regardless of the diagnostic group), as well as a specific effect on certain symptoms of atopic people. Indeed, it is possible to postulate that the ADHD presentation in the research groups of dietary responders, may be secondary to a primary mood variation affected by food in susceptible people.
Breakey J. Review article The role of diet and behaviour in childhood. Journal of Paediatrics
and Child Health 1997: Vol 33 No 3 190-194.
King DS. Can allergic exposure provoke psychological symptoms? A double-blind test. Biological Psychiatry 1981;16:3-7.
Wamboldt MZ. Multiple atopic disorders, adult depression may be linked. Am J Genet 2000:96: 146-49
Breakey J. Are you food sensitive? How to investigate your own diet. 1998 CE Breakey (Medical) Pty Ltd. Brisbane Australia. See www.FoodIntolerancePro.com
Breakey J, Connell HM, Reilly C. The role of food additives and chemicals in behavioural, learning, activity and sleep problems in children. In: Branen AR, Davidson PM, Salminen S, eds. Food Additives New York:Marcel Dekker, 2000.