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Obesity: a medical history

2007; Wiley; Volume: 8; Issue: s1 Linguagem: Inglês

10.1111/j.1467-789x.2007.00314.x

1467-789X

David Haslam,

Diet and metabolism studies

In the early spring of 1988, Gerald Reaven, Professor of Medicine at Stanford University, was struggling to prepare his Banting Award address for the American Diabetes Association Conference, when 'the notion of Syndrome X sprung almost full-blown into my mind' (1). Diseases, once seemingly unconnected, were drawn together under the banner of insulin resistance and presented as one life–threatening syndrome. For the first time, the clustering together of illnesses including heart disease, stroke, diabetes and dyslipidaemia was explained clearly and scientifically. On 1 September 2005, Sony's state-of-the-art anti-obesity weapon, Aibo the Robotic Dog, was launched in Tokyo. Wirelessly connected to scales, a pedometer and to a personal organizer recording food intake, Aibo has four stages of alertness: jumping and wagging its tail happily, playing 'funky music'; morose and lying inactive, playing 'dirges'; and two intermediate stages. The success of the dog's owner in controlling his own energy balance is reflected in the dog's mood. Although there have been major advances in the study of obesity, Aibo clearly demonstrates that the one thing the battle against obesity does not need is new scientific invention. Reaven's utterances proved pivotal, and nothing since has carried the gravitas of his proclamation. Aibo, on the other hand, will be consigned to history's waste bin. Uniquely among chronic diseases, lack of scientific knowledge is not a barrier to the successful treatment of a person who is obese. Whereas cancer treatment requires new drugs and heart disease updated techniques, obesity is different. We already know enough about the causes and how to manage it by diet, activity, drugs and surgery. The history of obesity is a history of failure. Looking back in time, however, gives us many insights as to treatment in the future. Obesity is changing, but its origins can be traced back 30 000 years, to our prehistoric ancestors. Survival of the fittest dictated that individuals who stored energy in the most efficient way would survive the inevitable fast and famine that would follow times of plenty. This has been attributed to the 'thrifty gene' (although no such individual gene exists), ensuring the continued dominance of our hunter–gatherer predecessors. But natural selection has turned on us. Life now favours inefficient phenotypes who fail to store energy in adipose depots, while those who lay down fat in the abdomen are condemned to premature death. To fight obesity, we are flying in the face of evolution and instinct, consciously countermanding the urge to eat for survival, and be as inactive as possible in order to conserve energy. Some 30 000 years ago, prehistoric statuettes, including the famous Venus of Willendorf, depicted anatomically accurate abdominally obese women. The function of these caricatures is hotly debated. They may have been fertility symbols – ironic in view of current knowledge that obesity causes infertility. Alternatively, the images, small enough to be carried round in the palm of the hand, may have been predecessors of Playboy magazine. Moses is considered to be the original writer on diet, recommending to the Jews, 'bread, wine, milk, honey; quadrupeds that divide the hoof, and chew the cud; all the feathered kind, a few only excepted; and fishes that have fins and scales'. Acceptance of obesity as a medical phenomenon has been slow. For thousands of years, overweight and obesity were exceptional, rarely seen and never studied. In some cultures, indeed, obesity was prized, indicating status and wealth. Only the richest had the means to become obese and girth advertised wealth more effectively than the richest clothing or jewels. The ancient Greeks were the first, however, to realize the dangers of obesity and its association with disease. Hippocrates understood that obesity led to infertility and early death, writing: In the beginning, man made use of the same food with the beasts, and it was the many distempers brought upon him by such indigestible aliment, which taught him, in length of time, to find out a different diet, better adapted to his constitution, teaching that . . . the spontaneous and crude productions of the earth must have shortened rather than lengthened their lives (2). Hippocrates also wrote about the illnesses caused by poor diet, and the improvement in health brought about by change of diet: 'The distempers arising from the coarse aliment which men at first made use of, obliged them to study the most proper methods of preparing bread from grain, and of dressing other vegetables as should render them more wholesome' . . . 'One cause which made it necessary to study the art of restoring lost health, was the great difference to be observed between the diet of the healthy and that of the sick' (2). The ancient Egyptians were primarily concerned with diet as a means of preservation of health, recognizing that quantity as well as quality of food was important. Their method of limiting food intake was primitive. They were said by Diodorus Siculus to: 'prevent distempers by glisters, purging, vomiting or fasting every second, third or fourth day', because 'the greatest part of the aliment we take is superfluous, which superfluity is cause of our distempers' (3). Herodotus agreed: 'Egyptians vomit and purge themselves thrice every month, with a view to preserve their health, which in their opinion is chiefly injured by their aliment' (4). Pythagoras recommended a different approach. Rather than eating too much, then vomiting or fasting, he advocated moderation: 'No man, who values his health, ought to trespass on the bounds of moderation, either in labour, diet or concubinage' (5). The physician Iccus expressed similar beliefs, combining exercise with diet to preserve health. The phrase 'the repast of Iccus' was used to describe a plain, temperate meal (6). Herodicus, one of Hippocrates' teachers, was successful in prolonging life, not least his own (7). He taught the regulation of diet and exercise, and was censured by Plato for 'keeping people with crazy constitutions alive to old age' rather than letting them 'better die out of the way'. Hippocrates developed theories on preservation of health, thousands of years ahead of his time. He correctly identified the energy balance equation: It is very injurious to health to take in more food than the constitution will bear, when, at the same time one uses no exercise to carry off this excess (8). . . . For as aliment fills, and exercise empties the body, the result of an exact equipoise between them must be to leave the body in the same state they found it, that is, in perfect health (2). Hippocrates' son-in-law, Polybus, continued the theme, hinting that diet and exercise might benefit fat individuals wishing to reduce, although the medical necessity to lose weight was not considered: Persons of a gross relaxed habit of body, the flabby, and red-haired, ought always to use a drying diet . . . Such as are fat, and desire to be lean, should use exercise fasting; should drink small liquors a little warm; should eat only once a day, and no more than will just satisfy their hunger (9). Celsus caused controversy by suggesting that a healthy individual should 'indulge himself at feasts; . . . sometimes eat and drink more than is proper', leading to suggestions that he was 'a patron of gluttons and drunkards' (10). Another great physician, Galen, wrote on food and diet, recounting one of the earliest case studies of obesity management: I reduced a huge fat fellow to a moderate size in a short time, by making him run every morning until he fell into a profuse sweat; I then had him rubbed hard, and put into a warm bath; after which I ordered him a small breakfast, and sent him to the warm bath a second time. Some hours after, I permitted him to eat freely of food, which afforded but little nourishment; and lastly, set him to some work which he was accustomed to for the remaining part of the day (11). Plutarch, although not a physician, made the connection between weight and health, observing: 'Thin people are generally the most healthy; we should not therefore indulge our appetites with delicacies or high living, for fear of growing corpulent' (12). The beliefs of great ancient physicians was carried forward by 'modern' European doctors and writers, in particular, Lewis Cornaro, and Sanctorius Sanctorius, who weighed his food and excreta over a period of 30 years. In Britain, corpulence was a problem for affluent sections of society. Physicians adopted the mantle of ancient writers, creating novel and original work. Sir Thomas Elyot was one of the first Britons to promote primary prevention of disease in his treatise The Castel of Helth (13). Later, Thomas Cogan recounted Hippocrates and Galen, adding his own shrewd analogies. On exercise: 'Flowing water does not corrupt, but that which standeth still; even so animal bodies exercised, are for the greatest part healthful; and such as be idle are subject to sickness' (14). William Vaughan wrote Directions for Health in 1607 with 'humour and smartness' comparing gluttony with excess alcohol. On alcohol: 'How shall toss-pots and swill-bowls be made to hate wine? Look on the countenance of a drunkard, and is it not disfigured? Does not his nose seem rotten, withered or worm eaten? Does not his breath stink, his tongue faulter? Is not his body crazy, and subject to gouts and dropsies?' He was equally forthright on food: 'For how is it possible, that the smoaky vapours which breathe from a fat and full paunch, should not interpose a thick mist of dullness between the body, and the body's light!' (15) Henry VIII's physician, former monk Dr Andrew Boorde, wrote a Breviary of Health in 1547, blaming alcohol as the cause of obesity: 'All sweet wines and grass wines doth make a man fat' (16). Most early texts on diet and exercise referred only to the preservation of health, rather than the cure of disease. John Armstrong wrote The Art of Preserving Health in 1744: Unless with exercise and manly toil You brace your nerves, and spur the lagging blood. The fat'ning clime let all the sons of ease Avoid; if indolence would wish to live. (17) And concerning diet: For this the watchful appetite was giv'n Daily with fresh materials to repair This unavoidable expence of life, This necessary waste of flesh and blood. (17) As the number of obese people increased, medical literature recognized the benefits to be gained from its reduction, usually because of discomfort or shortness of breath. Thomas Sydenham (1624–1689) acknowledged its multifactorial nature: 'corpulency may be ranked amongst the diseases arising from original imperfections in the functions of some of the organs, yet it must be admitted also, to be most intimately connected with our habits of life' (18). He elucidates 'moderation in eating and drinking is to be observed, so as on the one hand to avoid taking in more aliment than the stomach can conveniently digest, and of course increasing the disease thereby, and on the other hand defrauding the parts by immoderate abstinence' (19). The English physician Tobias Venner was the first physician to use the word 'obesity' in a medical context, calling specifically for its treatment in his Treatise in 1660 (20). His preferred remedy was the Waters at Bath, which, he maintained, were beneficial to such individuals: to make slender such bodies as are too grosse . . . Wherefore let those that feare obesity, that is, would not wax grosse, be careful to come often to our Baths: for by the use of them, according as the learned Physician shall direct, they may not only preserve their health, but also keep their bodies from being unseemly corpulent. Around the early 18th century, several authors promoted preservation of health as a reason to avoid obesity. In 1750, James Mackenzie wrote: I determined to prevent [illness], by acquainting those that will restrain their appetites, and hearken to reason, with the most effectual rules to preserve health: For certain it is, that from men's ignorance, or contempt of such rules, thousands never arrive at that period of life which their strength of constitution would have reached with proper care. (12) George Cheyne MD (1671–1743) was the foremost physician of his day, who himself suffered from gross obesity, weighing 32 stone at his peak, and feeling 'excessively fat, short-breath'd, lethargick and listless'. He required a servant to walk behind him carrying a stool on which to recover every few paces. Cheyne wrote of 'The Fat, unwieldy and over-grown', saying 'tis easier to preserve Health than to recover it, and to prevent Diseases than to cure them . . . without due Labour and Exercise, the Juices will thicken, the Joints will stiffen, the Nerves will relax, and on these Disorders, Chronical Distempers, and a crazy old Age must ensue' (21). The fact was becoming noted that obesity was not an isolated disorder, and that other conditions occurred more readily in obese patients. George Cheyne understood first hand the associated depression: '. . . a disgust or disrelish of Worldly Amusements and Creature Comforts . . . tumultuous, overbearing hurricanes in the mind'. He suffered skin disorders –'skorubtick ulcers'– and linked obesity with poor circulation; his blood 'one impenetrable Mass of Glew' and 'every vein and artery like so many black puddings'. In 1765, Joannes Baptista Morgagni recognized not only that obesity was linked to disease, but also, by anatomical dissection, that the position of the fat was crucial. In his Epistola anatoma clinica XXI, he describes a female with severe obesity and virili aspectu– manly, or virile aspect. The abdomen was prominent containing a large amount of fat accumulated in the intra-abdominal spaces and at the mediastinal level, with a raised diaphragm (22). It took another surgeon, William Wadd, to confirm Morgagni's work by post-mortem dissection (23). William Banting, who wrote the first commercially available diet programme (24), knew of the breathlessness obesity caused, and also described the joint pains, often then generically known as 'gout'; but the comorbidity of deafness led him to seek help from surgeon William Harvey, who identified the cause of his hearing loss as pressure from the fat around his neck compressing the airways. The low 'farinaceous' diet Banting was instructed to follow formed the basis of his book, and is the forerunner to the Atkins diet. Sleep apnoea was documented as being linked with obesity in the 4th century bc. Dionysius, himself obese, lived in fear of suffocating while asleep, and employed attendants to thrust needles through his sides to awaken him every time he slept. Hippocrates also described abnormal sleep patterns: 'Others, when their diet bears too great a proportion to their exercise, not only sleep well at night, but are likewise drowsy in the day; the repletion still increases, and their nights begin to grow restless; their sleep afterwards becomes disturbed with frightful dreams of battles' (25). The link between weight and women's health became increasingly recognized. In 1795, William Buchan (26) warned 'such girls as lead an indolent life, and eat great quantities of trash, are not only subject to obstructions of the menses, but likewise glandular obstructions; as the scrophula or king's evil'. For 'women of a gross or full habit', 'a spare thin diet' was called for, with only a small beer to liven it up. In 1811, Robert Thomas described the link with endometrial cancer, writing of menstrual discharges: When they happen to disappear suddenly in women of a full plethoric habit, such persons should be careful to confine themselves to a more spare diet than usual; they should likewise take regular exercise, and keep their body open by a use of some mild laxative . . . Should any scirrhous or cancerous affection of the uterus take place on a stoppage of menstrual flux, as sometimes happens, all that can be done in such a case is to have recourse to palliatives, such as opium, hyoscyamus, and hemlock, which may be combined (27). In 1806, Dr Shadrach Ricketson emphasized the gradually acquired, hidden diseases and death we now see as a result of over-eating: Let not the drunkard, the epicure, or the voluptuary say, that because he feels no immediate bad effects from his excesses, none are ever to follow: he may be assured, that if he persevere, weakness, disease, and, perhaps death, will, sooner or later, be the inevitable consequence . . . Fulness of blood, and corpulency, are the disagreeable effects of gluttony, which progressively relaxes the stomach, and punishes the offender with head-ach, fever, pain in the bowels, diarrhoea, and other disorders (28). Encyclopaedia Britannica commented: '. . . it may be justly doubted, whether gluttony and intemperance have not depopulated the world more, than even the sword, pestilence, and famine' (28). The main comorbidity linked to obesity is diabetes, a condition probably known to doctors since 1552 bc, when the Ebers papyrus (29) refers to 'excessive urination', and 'a medicine to drive away the passing of too much urine'. In Hindu writings, black ants detected diabetes thousands of years ago. Records describe a mysterious, deadly disease causing intense thirst, enormous urine output and wasting of the body. A diagnostic sign was the attraction of ants and flies to the victims' urine. In the 2nd century ad, Aretaeus the Cappadocian gave a detailed description of diabetes, for the first time hinting at the particular constitution that led to the condition: 'Diabetes is a wonderful affection, not very frequent among men, being a melting down of the flesh and limbs into urine. Its cause is of a cold and humid nature as in dropsy' (30). It is claimed that up to 80% of type 2 diabetes is linked to excess weight, but it is only relatively recently that the connection was highlighted. Nathan Buchan, in 1795, blamed 'hard drinking', but not corpulence. In 1811, Robert Thomas noted not only the presence, but also the site of body fat in cases of diabetes, highlighting dangerous metabolically active visceral fat: 'Fat within the thorax, abdomen, and pelvis, in some instances has seemed entirely converted into a gelatinous-like matter somewhat of an amber colour . . . The subcutaneous fat is found in general much diminished' (27). He continues to describe respiratory and other disorders specifically related to abdominal obesity: Corpulency, when it arrives at a certain height, becomes an absolute disease. The increase of the omentum particularly, and the accumulation of fat about the kidneys and mesentery, swell the abdomen, and obstruct the motions of the diaphragm; whence one reason of the difficulty of breathing, which is peculiar to corpulent people (27). Coronary heart disease commonly coexists with obesity. The condition now called angina was described by Edward Hyde (31), born 1609, but Hippocrates may have had the condition in mind: Persons, from repletion, especially such as are gross, sweat profusely in their sleep, which gives them no great uneasiness in the beginning; tho', in process of time, it becomes the cause of pain and distempers. And it is observable, that they are most apt to fall into this disorder, who, from a long habit of idleness, come, of a sudden, to use exercise. The term 'angina' was first used by Heberden in 1768. 'There is a disorder of the breast, marked with strong and peculiar symptoms, considerable for the kind of danger belonging to it . . . The seat of it and sense of strangling and anxiety with which it is attended may make it not improperly be called angina pectoris' (32). The connection between angina and obesity was emphasized later. In 1811, Robert Thomas wrote: It is found to attack men much more frequently than women, particularly those who have short necks, who are inclinable to corpulency, and who at the same time lead an inactive or sedentary life . . . he should endeavour to counteract any disposition to obesity, which has been considered a predisposing cause (27). By 1897, physicians such as William Osler were describing the causative factors of angina: '. . . an attendant rather of ease and luxury than of temperance and labour: on which account, though occurring among the poor, . . . more wise men than fools are its victims' (33). Osler presents a case study of 'Mr L, aged 55 years, merchant, who for a week had had attacks of severe pain in the region of the heart'. Although said to be 'a stout, large-framed man', his stoutness was not worthy of comment with regard to his 'severe attack of angina pectoris, accompanied with vomiting and sweating' (34). Gradually, the clustering together of different conditions in the presence of obesity was being documented. Dr Robert Thomas of Salisbury linked 'paralysis' or stroke, in 1811 (27), with 'full plethoric habit'. In 1795, Dr Nathan Buchan documented the effect on the skin in 'sedentary and studious' individuals: Sedentary artificers are not only hurt by pressure on the bowels, but also on the inferior extremities, which obstructs the circulation in these parts, and renders them weak and feeble . . . from whence proceed the scab, ulcerous sores, foul blotches, and other cutaneous disorders, so common among sedentary artificers (26). Morgagni, in 1765, highlighted the importance of abdominal fat by post-mortem dissection. More recently, in the 19th century, the link between maleness and obesity has been more clearly defined. According to the famed writer and wit, Brillat-Savarin: There is one kind of obesity that centres round the belly; I have never noticed it in women: since they are generally made up of softer tissues, no part of their body is spared when obesity attacks them. I call this type of fatness Gastrophoria, and its victims Gastrophores. I myself am in their company; but although I carry around with me a fairly prominent stomach, I still have well-formed lower legs, and calves as sinewy as the muscles of an Arabian steed (34). He is describing the typical, and dangerous apple shape which obese men tend to assume, as opposed to the 'pear' shape of obese women who often carry their weight harmlessly on the thighs and buttocks. French Physician Jean Vague revisited the same territory, and first described the now traditional 'apples' and 'pears' of android and gynoid obesity respectively, and gave an explanation as to the underlying metabolic derangements (35). The UK is now in the throes of an obesity epidemic, and risks following in the footsteps of America, where obesity has already delivered an epidemic of diabetes. Writers and physicians over many centuries have dedicated their life's work to teach the preservation of health, and warn of the dire consequences of ignoring good diet and activity. However, their wisdom has been disregarded. Life expectancy has been improving for centuries; advances in hygiene, science, public health and medicine have allowed longer and more productive lives. Obesity threatens to undo many of these gains. Could it even herald a reduction in life expectancy in coming generations? Instead of spending precious resources inventing novel scientific gadgets, the works of our forefathers should be revisited, and the simple lessons learned from history used to once again prioritize the preservation of health. No conflict of interest was declared.