Emotional and behavioural effects of food allergies/intolerances

Any experienced clinical or paediatric allergist must have encountered occasional cases where allergy and emotion are inter-related. I present seven case histories which illustrate the remarkable effects allergy or intolerance to food can have on behaviour, and might be of interest to the parents of children with behaviour problems.

Case 1 - Katherine

Katherine arrived for the consultation wearing a T shirt advertising COOP MILK, which was indeed the diagnosis. 

She had a history of being bottle fed, and had eczema from birth to age four, and had glue ears with grommets inserted twice. At age six school reports commented that behaviour and handwriting varied remarkably from day to day. Her mother had observed that she became very hyperactive and aggressive after eating anything containing dyes, especially yellow ‘smarties’. She had very heavy shadows under the eyes and high palate with distorted teeth. Blood tests were negative, but milk avoidance brought about dramatic improvement. The effects of milk on writing were remarkable, as shown.

In the ensuing years she made great progress both physically and emotionally, except when she had milk or milk chocolate, for which she had an addiction. The high palate and distorted teeth, which often result from unrecognised nasal allergy, resolved completely. 

When she indulged her craving for milk chocolate the effect was migraine headaches with visual disturbances, 'zombie like appearance', antisocial behaviour, and sleeping for up to 18 hours. Behaviour was described as aggressive and argumentative, with incessant crying and suicidal thoughts. In her teens it was difficult to persuade her to avoid milk and chocolate completely because of the craving, but she became a good athlete and won the county cross-country for her school. 

She went on to gain a very good degree in philosophy, but finally trained as a nurse. Aged 28 she still has cravings, and her husband comments that she undergoes a complete change in personality a few hours after eating milk chocolate. 

(Ed. See review of the Nutrition and Addiction handbook which includes chapters on both food addiction and chocolate addiction.)

Case 2 – Tara

Tara failed to thrive as a baby with frequent vomiting and diarrhoea, and was suspected of malabsorption. Beef and all Heinz baby foods (which have a beef broth base) were noted to cause severe diarrhoea. She gradually settled down, but was a miserable, undersized infant, and developed asthma from age two. When referred aged four she was 5cm below the third percentile and was so disturbed that she was impossible to examine. She had a deformed chest, wheezing and was very short of breath at rest, and was producing several floating stools per day. Her mother had asthma due to yeast, and grandmother had allergic aspergillosis.

Withdrawal of milk and beef products produced dramatic improvement in a few days with normal stools and behaviour. Test feeds repeatedly caused recurrence of asthma,  misbehaviour, and abnormal stools within a few hours. She grew 12.5cm (5”) in a year and the chest deformity disappeared. 

Case 3 - Jennifer 

Jennifer was aged ten, had strong family history of allergy, and was breast fed for one month. She developed eczema aged three months, and asthma with rhinitis from one year. When referred she was impossible to examine, and was very wheezy. Skin prick skin tests were positive for housedust, mites, grass pollen, and yeast but these tests were misleading.

She was initially given oral steroids to gain control of her severe asthma which responded dramatically, but her behaviour did not improve. Oral steroids were tapered off and inhaled steroids commenced to control the asthma, and egg and milk were also excluded as the feeding history suggested this possibility.
 
At this time she was referred to a psychiatrist, whose opinion was that she was 'infantile and demanding with unreasonable attitudes but with some manipulation would improve in time'. Within a month she was able to stop the inhaled steroid and had two colds without developing asthma as previously. Behaviour became normal and she began to grow rapidly. 

Both deliberate and unintentional ingestion of milk or egg caused irritability and misbehaviour within half an hour to such an extent that her mother said 'she seems to have a Jekyll and Hyde personality, depending on what she eats'. She grew 7.5cms in a year and developed normally thereafter. 

Case 4 – Paul

Paul vomited his formula feeds so actively that pyloric stenosis was suspected, and from one year old he had severe chronic rhinitis and a cough which almost drove his parents mad. He also developed severe indigestion, eczema, floating stools, hyperactivity, tantrums and antisocial behaviour. His parents consulted several physicians, but some blamed his  mother and others asserted that he was trying to attract attention. When referred aged six he was absolutely impossible to examine and refused to speak. 

Milk and egg were excluded because pyloric stenosis can be due to milk rejection, and within two days the cough and rhinitis ceased, and stools and his behaviour became normal. Challenge feeds repeatedly reproduced all the problems within an hour. Subsequently it was found that bread had similar effects, and that he had a craving for bread to the extent that he once ate a piece of bread from the bird table in the garden which caused a marked behaviour disturbance. His mother commented that 'milk and bread produce behaviour as foul as his stools'.

Further investigation established that he could tolerate gluten free bread, and that egg caused an acute gut reaction in two hours. Any trace of wheat flour would trigger the full blown syndrome, so gluten was the main allergen, but tests for coeliac disease were negative. Subsequent progress was uneventful and his growth and school progress  normal. Seen finally aged 23, he was quite normal and no longer had any difficulties with foods.

Case 5 – Bruce

Bruce suffered from chronic rhinitis from age of 18 months, was very backward at school and was diagnosed as dyslexic by the school phychologist aged ten. Another psychologist disagreed, considered that reading instruction had been defective, and found that he had a high IQ but the reading abilities of a child aged six. When aged eleven he was referred for allergy investigation of his rhinitis. 

He presented as an undersized, withdrawn, apathetic, and miserable child. The family history on the female side was that his mother was also a patient, and the maternal grandmother had rhinitis and migraine found to be caused by milk. Two great-uncles, one great-aunt, a great grandfather and a cousin were also unable to tolerate milk. Skin tests were all negative, but nasal provocation tests were positive for milk.

With avoidance of milk and all milk products he improved dramatically, but even a trace of milk repeatedly caused reversion to his previous emotional state, several times when taken accidentally. Within a few months his school work began to improve, and within a year he had caught up with his peers and remained top of his class with no problems with reading or any other subject.
 
Physically he developed very rapidly, and by age fourteen he was 178cm and was one of the best athletics in the school, but still reacted to even a trace of milk.

Case 6 – Christopher

Christopher was six when first seen, had been bottle fed, with feeding difficulties from the start with frequent vomiting, loose stools, and bloating. As he grew older his behaviour became worse and worse. His mother was sure that his problems were due to food, but a prominent paediatrician considered that the cause was faulty parenting and over-anxiety. She could not accept this and finally was referred to me.

At the first visit he was impossible to examine, cried and stamped his feet when approached, and seemed frightened, possibly suspecting that blood was to be taken again. After a detailed history and mother's detailed observations I thought that food was the most likely cause, and suggested that milk, potato, and gluten be avoided for a trial period. The improvement in his behaviour was remarkable, as a month later he allowed me to take blood for allergy tests, which were all negative.

His mother brought examples of his art work from school because it had changed from meaningless scribbles to recognisable objects and people. His behaviour had become normal, and school work improved beyond recognition. He became a very approachable little boy, but a trace of milk or potato would trigger misbehaviour.

Christopher's picture before the diet

Christopher's picture on the diet

Christopher's drawing before the diet

Christopher's drawing on the diet

His mother also noticed that the father was always bad-tempered and irritable on arriving home on Friday evenings, and established that this was triggered by having fish and chips on the way home. He did not have potato at any other time, and total avoidance ensured marital harmony.

Case 7 – John  

John was first seen aged nine with a remarkable history, commencing with severe difficulties with bottle feeding which resolved at 13 months to be replaced by incessant screaming and head-banging. His tantrums were uncontrollable, and by age two he tended to wander off and get lost if unsupervised. He was very clumsy, uncoordinated, and destructive. He would inflict pain on himself by pinching his arms and legs producing bruises, throw himself down the stairs, and kick holes in the walls.

His mother described him as a 'manipulative destructive monster' who made family life a nightmare and was threatening to break up the marriage. To preserve her sanity she placed him with a registered child minder and went back to teaching as head mistress of a local primary school. 

When he cut his head and required stitches at the local hospital he was found to be covered in bruises, so mother was sent for and accused of child abuse. She succeeded, but with great difficulty, in convincing the paediatrician that his injuries were self–inflicted. One can easily imagine the possible consequences to a head-mistress of an infant school!
 
At nursery and at infant school he was aggressive and anti-social, had frequent chest infections, and finally was diagnosed asthmatic. Behaviour became even worse, and he would run and jump on the spot making silly noises for long periods, repeatedly throw himself down the stairs, kick holes in the walls of his room, pinch himself, and sometimes cut himself, his clothes, or the furniture.

He was referred to a child psychiatrist who blamed his condition on parental mismanagement and their inability to communicate, and suggested that he was being provoked by his sister who was regarded as an angel by the parents. 

Eventually he was admitted to hospital with asthma and on discharge was referred for allergy investigation aged nine. I found that he was very allergic to the family cats, but he was no better after they were removed. 

On the evidence of his history I suggested that milk and all milk containing foods were  avoided, and within as little as a week he was transformed into a nice little boy with normal behaviour. Deliberate or accidental ingestion of milk or any milk products were repeatedly shown to produce dramatic reversion to his previous misbehaviour. His teachers at school,  could always tell if he had been cheating on his milk free diet by his behaviour.

Final comments

I have seen many other cases of allergy affecting the brain, but these are the most striking  and dramatic examples encountered in over fifty years experience. Unfortunately, in all but two cases it was impossible to follow them up to adulthood, so we will never know what happened to them and whether they finally became normal adults. 

Milk is the commonest cause of behavioural change but reactions to food dyes are not uncommon. The effects on behaviour of syrups and sweets containing dyes are sometimes  noted by observant mothers, but usually disbelieved and dismissed by their medical advisers. I once saw a child where yellow sweets would cause a rash around the mouth and vomiting with abdominal pains and visible peristalsis like snakes wriggling in the abdomen. (I wish I had had camcorder handy then.)

Allergy and intolerance to foods, especially milk, can affect any body system, and the affected system can change with time. For example, case 6 began with gut symptoms and eczema, which cleared only to be replaced by effects on the brain, and finally by asthma which led to the referral to an allergist. It is unfortunate that specialisation tends to prevent consideration of the body as a whole organism. Nowadays it is only the general practitioner who sees the patient as a whole, but lacks time to obtain a detailed history and recognise the association between food and behaviour so may refer the patient to the wrong special department. 
             
It is a most satisfying experience to transform a little demon into a normal child by simply altering the diet, thereby completely abolishing the antisocial behaviour which is driving  parents and family mad. Unfortunately there must be a great many cases where child and the whole family continue to suffer because the possibility that a food could be the cause is never considered. 

Altering the diets of young offenders has been shown to result in considerable improvements in behaviour at negligible cost. Unfortunately the authorities have paid little or no attention to these experiments which, when applied to prison diets on a large scale, have been shown to result in definite improvements in behaviour. 

Until the link between food and behaviour becomes generally known and accepted we will never know how frequently this association occurs. At the present time it usual to resort to suppressive drugs instead of trying to find a cause. Surely it would be make more sense to  try altering the diet, or at least avoid milk and milk products for a trial period, before resorting to drugs such as Ritalin.

Recent advances in brain scanning have made it possible to actually see the effects of  emotion on the brain, so it must also be possible to demonstrate the effects of a food to which the brain is allergic. To show objectively that food can affect the brain would confirm clinical observations and stimulate research directed at finding the cause of the problem,  rather than suppressing it with drugs.    

H Morrow Brown  MD FRCP(Edin) FAAAAI (USA)
International Fellow American Academy of Allergy, Asthma, and Immunology

You can reach Dr Morrow Brown via his website at www.allergiesexplained.com

First published December 2011

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