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Medical Papers

Food Addiction

Dr David L. J. Freed, MB, MD, MIBiol

You never hear a patient complaining "Oh doctor, I've got a nasty attack of addiction today!"

Addiction is one of those medical conditions that does not normally cause symptoms, and the patient is often unaware that there is anything wrong. We can only deduce the existence of addiction by observing the irrational behaviour of addicts. When for example we see a full-grown, intelligent man, who is otherwise completely rational, voluntarily inhaling tobacco smoke - a dangerous poison that kills 300 people a day - we know there must be something funny going on. A smoker never feels ill when he is actively inhaling tobacco smoke; on the contrary, that is the only time he feels completely "normal". Provided he is well stocked-up with cigarettes, the only time he feels ill is first thing in the morning, not having had a "fix" all night. For the rest of the day he feels fine, half the time quite unaware that his hands and lips are going through the automatic motions of smoking. The cigarettes themselves become almost invisible to him, so habituated is he. But he'll notice their absence, if he inadvertently runs low. Who else would you see at one in the morning, leaving his warm bed and driving miles through a blizzard to the motorway service station?

Smokers who quit, in common with alcoholics and heroin junkies who quit, all go through a phase called withdrawal syndrome. The features vary from substance to substance and from addict to addict, but all agree that it is an intensely unpleasant experience, and responsible for a lot of backsliding. It is largely through the study of withdrawal that we know about addiction, and it is clear that for all addicts, it is the imperceptible onset of very early withdrawal symptoms that triggers the next intake of substance. The smoker, for example, when preoccupied with something, will not normally notice that his hands have automatically reached for the cigarette pack and lighter. But if you interrupt him at that point and ask what he's doing and how he feels, you will see a little frown on his face; he actually doesn't feel all that good, and he knows that a cigarette is what he needs. Now watch the frown clear as he takes that first deep drag - ah!

The central paradox is that the same substance that the addict craves is also poisonous to him. Tobacco smoke causes cancer, heart disease and emphysema. Alcohol causes liver damage. Even marijuana, one of the safest of addictant substances, causes brain damage in the long term. The "benefit" of the addictant (if we can describe the temporary relief of returning to normality as a benefit) is very fast. The damage to health is very slow and variable. Again smoking provides the classic example; the "lift" that it gives comes within seconds, the health damage takes decades.

Some foods are addictant. Chocolate and coffee are common examples. Some of us eat chocolate because we like the taste, and others of us eat it because we have to. The "chocaholic" is classically female and fat. She eats chocolate because it comforts her. She needs comforting because she feels that people don't like her. In truth she does have a tendency to drive away friends, and this is because she has unaccountable "moods" of savage depression, which nobody likes.

The moods - of which she herself may be totally unaware - are caused by the withdrawal syndrome when she hasn't recently had chocolate. Chocolate withdrawal does not make the addict feel ill, but it does make her morose and resentful, and she will hotly deny your mild suggestion that she may be addicted. In fact, the heat and scorn of the denial are direct correlates of the depth of addiction; the more angry the patient gets at your suggestion, the stronger should be your diagnosis. Remember, the only time the chocaholic feels properly "normal" is when she has had a dose of chocolate, so ordinary commonsense (from her point of view) militates against your suggestion.

The coffee addict, on the other hand, is more likely male than female. He is quite prepared to admit his addiction, but instead hotly denies that it does him any harm. He just tends to be a bit sleepy when he relaxes after a hectic day.

If he needs to stay awake for an important meeting in the afternoon, he always gets himself a coffee to perk up with, and he drinks more during the meeting. Now watch him when he tries to give up. For the first week he keeps being overwhelmed by "attacks" of sleep, as irresistible as narcolepsy - just at the times of day when he used to drink coffee. After another week or two, this stops happening, and that background drowsiness that he always thought was "normal" has quietly disappeared. When he hasn't slept enough the night before, he feels tired - but he is no longer overwhelmed by irresistible weariness, and he stays awake easily enough in his afternoon meetings.

Morphine, caffeine, nicotine - the classic addictants - are all members of the group of natural heterocyclic nitrogenous organic compounds called alkaloids. Alkaloids are widely distributed in the Plant Kingdom and possess many powerful effects on humans, mostly harmful (although some are used for their pharmaceutic effects, for example digoxin, the foxglove alkaloid). Most alkaloids, if not all, interfere with the transmission of electrochemical messages within the nervous system, and most (if not all) are potentially addictive. Alkaloids occur in many food plants, such as the "nightshades" - members of the family Solenaceae. This family includes highly poisonous plants such as deadly nightshade and tobacco. It also contains less poisonous plants such as potato, tomato and capsicum. The difference between the more poisonous and less poisonous members of the group is only a difference of degree,the "edible" members having a somewhat smaller dose of alkaloid. The difference is actually not all that great; solanine from potatoes causes outbreaks of "food poisoning" from time to time.

Whilst it is not certain that addictive plants must necessarily also be poisonous, the association is so strong that it would be wise to assume it unless proved otherwise. The chocolate addict will no doubt assert that chocolate cannot possibly do any harm to anyone, but I am not so sure. Chocaholics are not healthy people; they tend to headaches, backache, irritable bowel, joint pains, nausea, and of course overweight, and all of these problems tend to dissipate when they give up chocolate. The same considerations apply to non-alkaloid addictants like alcohol.

Another, more recently discovered group of dietary addictants is the group called the exorphins. These tend to be peptide in nature (that is, they are formed by the partial digestion of proteins) and as the name implies, they act rather like a weak dose of morphine. Like morphine, they cause addiction as well as constipation and a peculiar dreamy euphoric feeling which patients describe as "being like an onlooker". Exorphins are found in wheat and other grains, as well as milk and soya. People with robust digestive systems can digest the proteins completely and do not suffer; people with weak digestions break down the proteins only partly, allowing the peptides to gain access to the circulation from the intestine.

Wheat, a rich source of exorphins, is of course eaten daily by most British people, in the form of bread, biscuits, cake, pastry and pasta, not to mention less obvious sources such as sausages and soya sauce. It is ubiquitous, and extremely difficult to avoid. Bread shares with tobacco the fascinating property of being virtually invisible; so habituated are people to bread that they often fail to notice its presence in the meal. It is the one food that they will forget, when telling you what they ate yesterday. It is also a rich source of lectins and other potential toxins, and is one of the commonest foods to be implicated in food intolerance states. (It is a central paradox of Nature that the most nutritious plant foodstuffs are also, by and large, the most toxic).

"Wheat addiction" may seem a preposterous notion, and the addict's hot denial of the possibility may seem commonsense. Most doctors also find it hard to believe, indeed the whole concept of being addicted to food seems bizarre because we need food, don't we, to stay alive? You wouldn't say we were addicted to oxygen, just because we feel rotten when it is removed! The key is that people are never addicted to all foods, only some. The "wheataholic" may be quite indifferent to cabbage or beef, the milk addict cares nothing for lentils. This proves that it is not "food" that the addict craves, it is that food. Try offering your child, when it is whingeing that it's "hungry", some nice brussels sprouts. If the child were really hungry, sprouts would seem delightful. He's not actually hungry, he's craving something (usually breakfast cereal with milk).

If you need proof, remember coeliac disease. Coeliacs love bread, but the proof of the pudding is quite literally in the eating. If the symptoms get better each time wheat is avoided, and return each time it is eaten, then however much the patient loves his bread he has got to give it up. Similarly with other wheat-induced conditions. Do not expect the patient himself to have an intuitive understanding of what you are saying to him. Both the addiction and the addictant are equally invisible to him. Remember, the only time he feels well is when he's having the item he's addicted to.

Wheat is the most commonly consumed member of the grain family - the edible grasses. The other common members are rye, barley, oats, maize (corn) and rice. Less common members include millet, quinoa, sorghum, spelt and millet. All share the same type of exorphins and lectins, but wheat is more commonly a cause of illness than the others because it is eaten more. Nevertheless, if a patient has a wheat problem, expect him also to have a problem (albeit not as bad) with the other grains. Another rich source of exorphins is milk, so it is not surprising to find exorphin addiction expressing itself, especially in children, in the form of a craving for breakfast cereals. It is common to find a child becoming gradually more faddy with food, until by the age of six he will eat virtually nothing except bread, biscuits and cake - plus bowl after bowl of breakfast cereal with milk. It is as if the grain and milk are jealous of competitors, and demand exclusive loyalty. The child's aversion to all other foods may become so severe that he will actually vomit everything else back, and the only things that will settle his stomach are grains (usually wheat) or milk. That pattern is diagnostic of wheat/milk intolerance - the very foods that seem to settle him and make him feel a bit better are the same foods which are giving him the symptoms complained of. He is very aware of the former phenomenon as it is quick, but he does not connect the food with the symptoms since they follow only hours (or weeks) later. Some symptoms (such as rheumatism) take years to become troublesome.

Put the child on a rigid grain/milk exclusion diet - reduction is not enough, it must be absolute avoidance. Offer him meat, fish, egg, or any vegetable. He will be unable to stomach it or even contemplate the thought. He will become deathly pale, and refuse all food and drink. He may become too weak to lift his head from the pillow. All this is an excellent sign that you are on precisely the right lines. The frightening withdrawal syndrome only lasts a day or two; in that time he will come to no harm. After a day or two he will eat some of the alternative food offered him, and will then quickly recover, both from the withdrawal syndrome and from the symptoms originally complained of. (NB Do not confuse the addicted child with the child who lacks appetite because of some chronic disease or because he cannot taste or smell. If he fails to perk up after 48 hours, abandon the experiment; there's something else wrong).

But if all goes well, grain and milk must then be avoided religiously for many months, perhaps years, as it will only take a morsel to re-addict him all over again, and start up all the old symptoms again. Precisely the same pattern is seen with chocolate or coffee addiction, except that the exact form of withdrawal syndromes are somewhat different, and no other foodstuff but wheat seems to demand the exclusive "loyalty" of its adherents that wheat does. Probably all foods can sometimes be addictant, but the commonest by far are grains (principally wheat), milk, chocolate, tea, coffee, cola drinks, and the nightshade vegetables (tomato, potato, chili, capsicum).

After avoidance of an addictant food, re-challenge with that food weeks later can provoke swift severe reactions - a process Randolph (see below) termed "unmasking". Such reactions can sometimes be of educational value, convincing the patient that the food was after all damaging his health, but reactions can also be dangerous. Re-challenge with milk has caused fatalities (5).

Clinical Aspects

The American allergist Theron Randolph recognised the addictive eating pattern in some of his patients, and deduced, logically, that any food that is taken daily or more often is likely to be responsible, at least in part, for whatever symptoms the patients were complaining of. He persuaded them to give up the suspect foods, and indeed observed in many cases that the symptoms dissipated. But before that, he observed a classic withdrawal syndrome, with aggravation of existing symptoms, headaches, extreme weakness, loss of appetite, and pallor. Once the withdrawal syndrome has abated, reintroduction of foods may cause swift and severe reactions ("unmasking").

NB. A classic part of the withdrawal syndrome is resentment. The patient blames the allergist for the predicament he is in, and will frequently argue the doctor's intelligence or honesty. The allergist learns not to lose his temper; patients in withdrawal are not behaving rationally and are not responsible for the hostility they feel. Surprisingly, few patients even in the depths of depression withdraw entirely from the allergist's care, but what they all do is demand the allergist's approval and permission for them to break the diet. In the patient's own best interests, the doctor must resist all pressures; indeed in my view it would be dishonest to give in - we doctors do not have the power to change Nature or grant special dispensations.

Randolph termed the food-addiction type of illness "masked allergy", thereby unwittingly causing a giant step backwards in medical understanding as immunologists world wide pounced on his alleged misuse of the "allergy"concept, which they regard as their parochial possession. The symptoms are indeed not those of classic allergies (sneezes, wheezes or itches), rather, they include such "vague" symptoms as headaches, rheumatism, fluid retention, mood swings and childhood hyperactivity. Another cause for ridiculing Randolph's concept is of course that most people eat the same foods every day, more or less, and apparently come to no harm. Randolph would answer that he is not concerned with "most people", only with the chronic sick, and they are unusually susceptible to this effect.

Note that "masked allergy" is a diagnosis that can only really be made in retrospect, once you have watched the patient improve after an initial aggravation. Until that moment, it is wise not to use the term, as it invites conventional doctors to demand your proof, and you haven't got any yet. All you should say to the patient at the outset is "Well, experience leads me to think that if you omit these foods and drinks, you will feel worse for a while and after that very much better. I think it might be what we call masked allergy."

The paragraph below makes reference to Information Sheet 3

Conventional allergy tests are negative in these cases. The only way to demonstrate that the illness is caused by a certain food or foods is by withdrawal-and-challenge, as described in Information Sheet 3, and it is noteworthy how slow both phases are. In Egger's classic studies on hyperactivity and migraine at Great Ormond Street (1,2), and Alun Jones's on irritable bowel at Cambridge (3), at least two weeks had to be allowed for each withdrawal phase and each challenge. It is a tribute to those involved in these studies - both scientists and patients - that the studies were performed at all. Thanks to those studies we now know that food intolerance can indeed cause many cases of chronic illness.

The foodstuffs characteristically responsible are milk, cheese, wheat, yeast, food additives (preservatives, dyes and other "E numbers"), chocolate, sugar and citrus fruits, but there is no food which is universally safe in this group of patients. No diagnostic test is reliable, except for the laborious process of withdrawal-and-challenge, and that too has many problems both practical and theoretical (4). In my view the most cost-effective procedure is to assume that the patient does indeed have food intolerances, probably multiple, and proceed immediately to a few-foods ("oligoantigenic") diet, coupled with a comprehensive desensitising vaccine to protect him against those foods which he must eat. Once the symptoms have gone, I desensitise for more and more foods in the hope of eventually returning the patient to a more normal diet. Successful treatment indicates that the presumptive diagnosis was probably correct. Although we end up never knowing the diagnosis for sure, the whole process is quicker and cheaper than the withdrawal-and-challenge approach and also has a good chance of making the patient better.


Suspect food addiction where:
there are chronic "vague" symptoms of unknown cause;
any food or foods are being taken daily, especially if:
the patient has cravings for that food, or
hotly denies the possibility that he is addicted to it, or that
it is doing any harm
NB: If he expresses doubts about your sanity, the diagnosis is confirmed.


1) Egger J, Carter CM, Wilson J et al:
'Is migraine food allergy?'
Lancet (1983), ii: 865-8.

2) Egger J, Carter CM, Graham PJ et al:
'Controlled trial of oligoantigenic diet treatment in the hyperkinetic syndrome'.
Lancet (1985) i: 540-5.

3) Alun Jones V, McLaughlan P, Shorthouse M et al:
'Food intolerance: a major factor in the pathogenesis of irritable bowel syndrome'.
Lancet (1982) ii: 115-7.

4) Freed DLJ:
'Laboratory diagnosis of food intolerance'.
in Brostoff J, Challacombe SJ (eds)
Food Allergy and Intolerance,
Bailliere Tindall, Eastbourne, 1987, 873-97.

5) David TJ:
'Anaphylactic shock during elimination diets for severe atopic eczema'.
Arch Dis Child (1984), 59: 983-6.

I thank NHA Research, Brighton, (01273-424185) for background information about tobacco addiction.

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