In 1974 a self-help book written by Ben F. Feingold (1899-1982) entitled Why Your Child is Hyperactive arrived on the shelves of book stores across North America. On the surface, Feingold's book was not particularly exceptional. By the mid 1970s hyperactivity (known today as Attention-Deficit/Hyperactivity Disorder or ADHD) was the most commonly diagnosed childhood psychiatric disorder, estimated to affect at least five per cent of children. Countless other self-help books, medical texts and journal articles addressed hyperactivity, and the media regularly showcased the disorder on television talk shows, call-in radio programmes and in newspaper stories.
But Feingold's book was not a typical hyperactivity handbook. Instead of attributing the disorder to genetic neurological dysfunction, as most psychiatrists did by the mid-1970s, Feingold, a prominent San Francisco allergist, blamed the large amounts of food colourings, flavourings and preservatives consumed by the average American child. More importantly, Feingold claimed that hyperactivity could be prevented by adopting a food-additive-free diet which was subsequently nicknamed the 'Feingold diet'.
It did not take long for the Feingold diet to attract enormous attention from physicians, the media and parents of hyperactive children. For parents, Feingold's theory was attractive in two important ways. First, it tapped into contemporary fears about chemicals in the food supply raised by the publication of Rachel Carson's Silent Spring in 1961. By the 1970s Carson's concerns about pesticides had been applied to other food chemicals and channelled into a thriving organic food movement. Second, the Feingold diet gave parents an alternative to treating their hyperactive children with controversial stimulant drugs, such as Ritalin, the prevailing medical response to the disorder. Recognising the popularity of Feingold's idea, the media made a minor celebrity of the septuagenarian allergist and featured him on television and radio programmes such as the Phil Donahue Show and Today, and in print publications ranging from the New York Times and Newsweek to the National Inquirer. Parents impressed by the effectiveness of the Feingold diet formed hundreds of Feingold Associations across North America which advised families on how to employ the diet.
The medical community, however, was not as impressed. Suspicious of Feingold's clinical observations, his motives and the efficacy of his diet, they designed dozens of clinical trials to test his hypothesis during the 1970s and early 1980s. The overwhelming opinion that emerged out of these trials was that Feingold's theory was incorrect and, following Feingold's death in 1982, medical and media interest in the Feingold diet withered away.
Most physicians treating hyperactive children today would argue that this concluded Feingold's story: scientific testing proved that food additives did not cause hyperactivity, and that the Feingold diet would be a fruitless imposition on families. However, an examination of the broader context within which Feingold developed his theory, the many factors that shaped the diet's clinical evaluation and eventual rejection, as well as recent developments in the history of the Feingold diet, suggest that this is not the case.
A myriad of political, economic, methodological and social factors combined to undermine Feingold's theory and relegate it to the margins of medicine. The history of the Feingold diet not only demonstrates the many difficulties inherent in turning novel medical ideas into medical knowledge, but also that historical analysis can provide crucial insight into how medical controversies are resolved, especially when the outcomes of such controversies are flawed.
Almost immediately after Feingold produced his theory of hyperactivity, physicians began expressing doubts about his diet. They also began testing it to see if their observations matched those of Feingold. Although their list of reservations grew long, a closer look at them, as well as the design and interpretation of the tests of the Feingold diet, raises questions about how such firm conclusions were thought to be warranted and why they were made.
The chief claim of physicians opposed to Feingold's theory was that the clinical trials designed to test it proved definitively that the Feingold diet did not improve the behaviour of hyperactive children. The problem with this claim is that the trials actually provided a mix of negative, neutral and positive results. Moreover, most of the trials conducted in the years following Feingold's death yielded positive results. Even more puzzling were reviews of the trials of the Feingold diet which analysed, summarised and assessed the sum total of trials conducted to test the Feingold's theory. Although these reviews were supposed to be unbiased, review authors who were opposed to the diet ignored trials that provided support for Feingold's theory and, on the other hand, positive reviewers were guilty of omitting negative findings.
Equally problematic were the bold conclusions made by investigators based on trials they conducted that were fraught with methodological problems. As most researchers attested, testing the Feingold diet was a methodological nightmare. Feingold claimed that children could react to thousands of food additives, as well as certain fruits and vegetables, but also that not all children reacted to the same substances. Regardless, most researchers only tested one food additive, such as Red Dye #40, and restricted their studies to small groups of children. There were also disputes about what quantity of food additives reflected the typical amounts consumed by children. Although some studied used as little as 20mg of a particular chemical, others used up ten times as much.
Recruiting reliable subjects for trials that ideally demanded large sample sizes was complicated, expensive, and frustrating. It was also difficult to retain children as subjects, especially if they reacted strongly when challenged with a particular food additive after experiencing success on the diet. Many parents disliked seeing a return to the problematic behaviour, even if it was to show that the diet worked. Maintaining strict compliance to the Feingold diet during month-long trials was difficult to enforce and assess.
Moreover, there was potential for bias in many of the trials due to sponsorship. The Nutrition Foundation, a so-called research organisation funded by food manufacturers, food-additive producers and pharmaceutical companies such as Coca Cola, Dow Chemical and Miles Laboratories, not only funded many of the trials, they also provided some of the foods to be tested. Not surprisingly, the trials in which the Nutrition Foundation participated produced uniformly negative results.
Finally, researchers differed markedly with regards to how they interpreted the trial results. In one case, a sample of pre-school children were tested alongside a sample of elementary-aged children, and were found to respond more positively to the Feingold diet than the older group. This accorded with Feingold's observation that younger children tended to react more dramatically to additives and, therefore, responded better to his diet. Despite this, the investigators, who were funded by the Nutrition Foundation, determined that the results in the younger sample were invalid and emphasised their less dramatic observations of the older group. In contrast, investigators of a trial consisting of twenty-two children found that only two of them reacted to food additives. Regardless, the investigators considered their findings to be in favour of Feingold's hypothesis.
It is difficult to see how physicians could have drawn definitive conclusions from the trials conducted to test the Feingold diet. Indeed, most investigators, including Feingold's supporters and detractors, urged that more research be done to explore further the link between food additives and behaviour. Although such trials appeared sporadically after Feingold's death in 1982, almost all lent support to Feingold's hypothesis. Nevertheless, they tended not to attract the media attention that accompanied earlier trials, and were typically ignored by physicians.
While Feingold's critics were using results from the trials to attack his hypothesis, they also had other complaints. One was that Feingold had taken his hypothesis to the media and the public before submitting it to the scrutiny of his medical peers. And by doing so, Feingold's detractors contended, he was no better than a quack snake-oil salesman or a 'medical pied piper'. Moreover, they believed that Feingold's popularity, combined with his charisma and grandfatherly charm, could not only convince parents to try the diet, but could also cause a placebo effect. In other words, parents who saw Feingold on television were so impressed by him and his theory that, when they tried the diet for themselves, their high expectations of success blinded them to its actual effects. Many physicians also argued that the extra time and attention parents took in changing their hyperactive child's diet provided the attention he/she craved and that this, not a different diet, was what caused the cessation of troublesome behaviour.
Grievances about Feingold's popular approach, however, were not altogether justified. It was correct that Feingold took almost every opportunity to publicise his theory, even accepting interview requests from the tabloid National Enquirer. But it was not true that Feingold took his theory to the masses before seeking the approbation of his medical colleagues. Prior to writing Why Your Child is Hyperactive, Feingold presented his theory at the 1973 and 1974 conferences of the American Medical Association (AMA). Cognisant of the potential appeal of Feingold's theory, the AMA organised press conferences to precede Feingold's presentation and eighty members of the international press turned out to hear about food additives and hyperactivity.
Encouraged by the AMA's apparent interest in his theory, Feingold wrote up his observations and submitted them to be published in the AMA's journal, JAMA, and later to the British Medical Journal and the Western Journal of Medicine. To Feingold's dismay, each submission was rejected. The goodwill previously expressed by the AMA had apparently run its course. Although it is difficult to prove why this occurred, it is likely that the influence of the Nutrition Foundation as well as pharmaceutical companies, whose advertisements filled the pages of such journals, was significant. Feingold, well into his mid-seventies and battling his own health problems, had to decide how best to spread his message about food additives and hyperactivity. Soon after these rejections the American publishing giant, Random House, offered to publish his theory in a more popular format and, realising that he would be more likely to convince parents than physicians, Feingold wrote Why Your Child is Hyperactive.
Although Feingold's overall attention switched from the medical community to parents, he still attempted to convince medical professionals that his theory was sound and that his diet worked. The title of Feingold's book certainly suggested that its target audience was parents, but close examination of many passages which elaborate on scientific theory and refer to leading researchers reveals that the book was written with physicians also in mind. Furthermore, Feingold persevered in writing for scientific journals and eventually published a dozen articles about his theory, albeit in less-renowned journals such as Ecology of Disease, the American Journal of Nursing and the Delaware Medical Journal.
Physicians opposed to Feingold's theory expressed many other reservations, including concerns that it reduced the amount of vitamin C consumed by children (since certain fruits and vegetables could be problematic), that it only applied to a small percentage of hyperactive children and that it encouraged children to be picky eaters. Much like other qualms about the Feingold diet, these were questionable. For example, most children were only sensitive to one or two fruits, and Feingold strongly urged that parents re-introduce other fruits and vegetables when it was clear that they caused no reaction.
The percentage of children who reacted to additives was always a thorny issue; while Feingold suggested that up to 75 per cent of hyperactive children could be helped by his diet, others thought that only 5 per cent or fewer were affected. But considering that 5 per cent amounted to a large number of the millions of children diagnosed with hyperactivity by the mid-1970s, and the fact that other solutions, including stimulant drugs, failed to work for large numbers of children, this argument was also quite disingenuous.
Finally, concern that the diet encouraged picky eating was moot, partly because one of the side effects of hyperactivity drugs was appetite suppression (a more serious type of fussy eating), but also because the elimination of so much processed food meant that children consumed less salt, sugar and fat. In other words, it promoted the sort of selective eating that most nutritionists would presumably support.
The final, and most crucial, reservation made about the Feingold diet was much more difficult to refute. This was that, as one critic put it, the Feingold diet was 'a difficult and exacting regimen which put considerable strain on the whole family'. The inherent difficulty in weaning children off artificial colours and flavours was described neatly in a trial of the diet conducted at a summer camp for learning-disabled children: 'the children were not happy with the Feingold diet. The teachers had the feeling that there would have been a rebellion had it lasted longer than a week. They particularly disliked the colourlessness of the food, and missed the mustard and ketchup ... The strict Feingold diet appears to be distasteful to the typical American child'. Reading comments such as these, physicians were reluctant to recommend the diet and tempt additional failure and strife in families which were already dealing with difficult circumstances.
To some extent such hesitance was justifiable. The Feingold diet, like any diet, was difficult. Although the Feingold Association would send lists of acceptable food products, during the early years of the diet these lists were small and meant that parents, usually mothers, were left on their own to interpret incomprehensible and uncomprehensive labels, bake their own bread, cookies and candy and forgo some of their family's favourite foods. Controlling diet outside of the home forced mothers to investigate what their children consumed at school, birthday parties, and at the convenience store - no junk food, coloured icing, or colas were allowed. Given the need for complete compliance, and the fact that hyperactive children tended to be defiant, inattentive, and impulsive, a child's carelessness, indifference or resistance was thought to pose a significant obstacle.
But despite the discouragement of physicians, the incredulity of teachers, family and friends and the inherent complications of the diet itself, tens of thousands of families ignored the mainstream approach to hyperactivity and became Feingold families. Furthermore, a large percentage of these families found the Feingold diet to work and have stayed with it to this day. While Feingold believed that 70 per cent of the families to whom he prescribed the diet found it to work, today the Feingold Association claims that 90 per cent of families who try the diet today are successful.
Most parents and children interviewed about their experiences on the Feingold diet agree that it is an arduous regimen, especially at first when they have to empty their cupboards and search their supermarket for acceptable items. But many of the claims made by Feingold's opponents about the diet's difficulty have not been substantiated by families' experiences. This has been partly because of the weakness of some of their arguments, but also because of the ability and desire of most Feingold families to overcome such difficulties.
Indeed, some of the characteristics shared by most Feingold families have unquestionably helped them succeed on the diet. These include parents with university education, particularly (and interestingly) in the sciences, a comfortable standard of living (often to the point where one parent is able to stay at home or work only part time), domestic harmony and, perhaps most importantly, the willpower to follow through with the diet. Many such parents defied their physicians' advice, negotiated with schools about providing Feingold-friendly lunches and snacks, adjusted the diet to meet their specifications, found ways of adapting to childhood celebrations such as Halloween and birthdays and brought their own food to family functions even when relatives scoffed. Most interestingly, in the vast majority of cases examined, the children themselves found that the diet was beneficial and, instead of looking at ways to cheat, assertively refused problem food when offered.
Although it could be argued that most American families are not so fortunate and, therefore, that the diet would not be beneficial to them, such a claim would overlook two crucial factors in the history of the Feingold diet. First, the success of Feingold families during the last thirty years has been in spite of countless obstacles, including medical, pharmaceutical and food industry opposition to the diet, poor labelling laws and a cornucopia of additive-laden products, omnipresent, albeit controversial, pharmaceutical alternatives to treat hyperactivity and the overwhelming perception in the media since Feingold's death that his diet was simply a fad.
The second factor leads from the first and can be summed up best in the form of a question: why, given all of these hurdles, did families stick with the diet, some for over thirty years, if the diet did not work? In other words, if many of these factors changed or had been different, it is possible that a large proportion of hyperactive children could have benefited from the Feingold diet.
In early 2008, the American Academy of Pediatrics did something it rarely does. It admitted that it might have made a mistake. Following the publication of yet another trial which supported the Feingold diet, and after four decades of rejecting the Feingold diet as a possible mode of treatment for hyperactivity, the AAP stated that 'the overall findings of the study are clear and require that even we skeptics, who have long doubted parental claims of the effects of various foods on the behavior of their children, admit we might have been wrong'.
There are two important health-policy implications of this admission which attest to how historical analysis has a crucial role in, if not prescribing health policy, then at least assessing the effectiveness of such policies. The first is that the AAP's about-face was about much more than a new study. As stressed in this paper, there were dozens of trials which pointed to the effectiveness of the Feingold diet, the most positive of which were published during the last twenty years. The findings of the trial cited by the AAP not only came to the same conclusions as many earlier trials, but the same University of Southampton researchers had already published similar findings in a 2004 study. The significance of their new study did not have as much to do with the findings themselves as with the historical context into which they emerged.
In particular, many dynamics, including concern about the health of the food supply, growing consumer wariness about drugs and new information technologies intervened to re-invigorate interest in the Feingold diet. Food-supply disasters such as the Bovine Spungiform Encephalopathy (BSE) crisis during the 1990s, as well as the corresponding rise of the organic food movement and concerns about childhood obesity, spurred renewed interest in the safety of food found on supermarket shelves.
In the United Kingdom, for example, celebrity chef Jamie Oliver spearheaded a campaign to provide additive-free, organic, and seasonal food in school cafeterias and, in 2005, the Blair government pledged 280 million pounds of support. On his 'Feed Me Better' website, Oliver listed 'poor concentration', 'hyperactivity and behavioural problems', and 'mood swings', as effects of the 'processed junk foods' served in schools. Some British supermarket chains now voluntarily use natural dyes, such as beetroot, instead of those made from petrochemicals. Furthermore, the explosion in the rates of peanut and other food-allergy diagnoses led to tougher labelling legislation in North America and raised the awareness and acceptance of food sensitivities generally, particularly those affecting children.
In addition, the conventional treatment of hyperactivity using stimulants came under intense suspicion as certain hyperactivity drugs, as well as drugs to treat depression and pain, were found to be dangerous, or in some cases, simply ineffective. The hyperactivity drug Adderall, for example, was temporarily removed from shelves by Health Canada in February 2005 for its role in the sudden deaths of twenty children and adults. Moreover, a recent study at the University of Hull concluded that the drugs used to treat millions of depressive patients do little more than act as placebos. Finally, the emergence of the Internet gave the Feingold Association an invaluable tool to market Feingold's theory by telling success stories, demonstrating research results and accumulating more comprehensive lists of Feingold-friendly foods.
The importance of these factors in sparking interest in the Feingold diet in 2008, thirty-five years after Feingold's first press conference, demonstrate that medical solutions can only become authoritative under certain social conditions. The corollary to this is that the makers of health policy, the physicians and legislators who ultimately resolve debates about novel medical ideas, are well served if they use historical analysis to assess all of the factors, especially the non-scientific ones, that contribute to the development of medical knowledge. Whose interests are served by medicating millions of hyperactive children? Whose interests are not served by taking colourings, flavourings and preservatives out of the food supply? The questions historians ask about medical history should perhaps reflect those asked about health policy.
The second aspect of the AAP's statement that is particularly interesting, and especially pertinent to medical historians, is its remark about doubting 'parental claims of the effects of various foods on the behavior of their children'. Medical historians have long agonised about conducting 'history from below' or patient-centred history, that is, looking at the history of health provision from the perspective of the patient, rather than from the gaze of famous medical researchers or hospital administrators. It is a 'difficult and exacting' enterprise itself, but one that can yield surprising results. For the history of the Feingold diet, the experience of patients and parents is not only a key part of the story, but also helps to answer the question at the root of the whole enterprise, namely, did the Feingold diet work? And at the very least, the history of the Feingold diet demonstrates that, yes, it worked for them.
If this conclusion is correct, then it is a call to medical historians, as well as physicians, to expand their understanding of what constitutes medical knowledge. For thousands of Feingold families, the opinion of the AAP and other medical associations that the Feingold diet was quackery was ultimately irrelevant because, for them, the Feingold diet was unequivocally medical knowledge. If the AAP's admission is any indication, then the parents and patients were right and the paediatricians were wrong.
For medical historians, this re-affirms the value of patient-centred history, both as an historical enterprise, and as a means to apply historical knowledge to contemporary debates about not only health, but other matters of social policy. For physicians, and those who determine health policy, it is a signal that they, too, might be advised to avert their gaze from the laboratory and, instead, re-direct it at the patient.
Flurin Condrau, 'The patient's view meets the clinical gaze', Social History of Medicine, 20:3, 2007, 525-40.
Erika Dyck, 'Hitting highs at rock bottom: LSD treatment for alcoholism, 1950-1970', Social History of Medicine, 19:2, 2006, 313-29.
Ben F. Feingold, Why Your Child is Hyperactive (New York, Random House, 1974).
Harry Hendrick, Child Welfare: Historical dimensions, contemporary debate (Bristol, Policy, 2003).
Mark Jackson, Allergy: The history of a modern malady (London, Reaktion, 2006).
Gregg Mittman, Breathing Space: How allergies shape our lives and landscape (New Haven, Yale University Press, 2007).
Jack Pressman, Last Resort: Psychosurgery and the limits of modern medicine (Cambridge, Cambridge University Press, 1998).
Matthew Smith, 'Into the mouths of babes: hyperactivity, food additives and the reception of the Feingold diet' in Mark Jackson (ed.) Health and the Modern Home (New York: Routledge, 2007), 304-21.
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