Muddled Thinking Is Hard to Swallow

Ever since I first became involved in research in 1932 I have been struck by the difference in quality of the thinking of even quite emi- nent scientists when they apply their minds, on the one hand, to their own specialized subjects and, on the other hand, to affairs of everyday life. Nor am I restricting my comments to the phenomenon of the distinguished Fellow of the Royal Society at the peak of a creative career who shows himself in committee to lack common sense, to say the least, when confronted by administrative problems of a university department. My point is that, all too often, the brilliant biochemist who may be able not only to spot the existence of, let us say, a previously undiscovered vitamin but then to determine its exact chemical configuration can then become involved in the intellectual “thick- ness” that people’s health will benefit by supplementing with the newly discovered vitamin what they have quite happily been eating before. This may follow—but then again it may not. They were exciting times, 50 years ago, when, one after another, these “accessory food factors” yielded to the analytical skills of those studying them. Underlying the chemical virtuosity that resulted in pure crystalline vitamin C, for example, were colonies of scorbutic guinea pigs, the relief of whose aching jaws was proportional to the vitamin content of the gradually more refined preparations from the chemical laboratory. There could hardly have been a more inconvenient measure. Later it transpired that the reason why more manageable test species than guinea pigs—say, rats or mice—could not have been used was that, besides guinea pigs, only even less amenable fruit-eating bats, bulbul birds, apes or people needed any dietary vitamin C at all. Clear thinking comparatively soon elucidated the structure of the vitamin and something of its biochemical function. But then came a more muddled level of thought. Wellmeaning “expert” committees persuaded themselves that the health of their fellow citizens would benefit from more vitamin C than their forebears ate, although the figure recommended later on was less than half of the one first proposed. Some even implied that human life could only be successfully maintained by a glass of orange juice a day. My own colleagues tried to persuade coal miners to exchange their heaped plates of meat and vegetables for a salad, ignoring the fact that, in a community in which potatoes had been common in the diet for at least two centuries, scurvy was never seen, even among its poorest members. Some of my own research focused on thiamine (vitamin B1). I recall with pleasure constructing an imtrument for measuring fluorescence to assess the concentration of this vitamin; this was a major advance over feeding preparations made from rice polishings to polyneuritic rats. Sir Rudolf Peters at Oxford did better using thiamine-deprived pigeons with which he elegantly demonstrated the vitamin’s exact biochemical role. This was brilliant thinking. Yet it was accompanied by a solemn argument that superior health might be attained by adding to the diet brown bread, richer in vitamin B1 than white bread, which might be further reduced in vitamim by being toasted. All this, be it remembered, for a community in which beriberi—a disease caused by vitamin B1 deprivation—never occurred, even among its most deprived and least well-fed. The intellectual jump from biochemistry to practical affairs has proved difficult. Fifty years ago, grocery items were believed harmful if they lacked these newly discovered “accessories.” Lack of a particular vitamin or mineral, even if not manifested by clinical evidence, was often blamed by “expert” thought of the less rigorous sort for insidious if invisible “subelinical” symptoms. In time, however, such articles of faith came to lack allure. There was so little to see. In 1959 a new phase in dietetic thought began. In that year. Ancel and Margaret Keys published their book, Eat Well and Stay Well, linking diet, cholesterol and coronary heart disease. This era persists today. It deserves (but seldom gets) thinking of a high order, encompassing clinical subtlety and understanding of the balance of cholesterol within the system as well as some philosophical assessment of what can be expected within the human life span. The prevention of infectious diseases has been a major scientific achievement, and progress has been made in dealing with degenerative conditions. To some people it would almost seem that the time has come when we can anticipate that every malady could one day be controllable. If so, what then? Surely we have to die of something. Yet even within this wide area of speculation there remains space for clear thinking about the metabolism of cholesterol, animal fats, vegetable oils and heart disease. In parallel, however, is an even greater opportunity for irrationality. If researchers 50 years ago had to overcome the complexities arising from the use of guinea pigs, polyneuritic rats and pigeons as measuring instruments, what is to be done in the present age of statistics on heart attacks in which obesity, muscular activity, hypertension, gout, stress, age, diabetes, cigarette smoking, family inheritance and gender all play a part before any influence of such combinations as fried fish and chips for supper can be assessed? Much is made today of the importance of nutrition education. But what is to be taught, and how useful will the teaching be? How good is the thinking behind it? Within my first quarter-century in food science the teaching was that food commodities were bad if they could be argued to contain too little of some minor ingredient—regardless of what the diet as a whole might provide or of the lack of evidence of any harm having been done. Now, in my second quarter-century, much of the first quarter-century’s debate is forgotten, and boiled eggs, milk, butter, cheese and roast beef are bad because they are said to contain too much cholesterol or animal fat. Yet evidence of harmfulness is not totally convincing. I wonder what the next quarter-century will bring. Nor have I much confidence that, even if I eat my vitamins and pass up roast beef and Stilton cheese, I shall survive long enough to find out. A skillful, garrulous and idiosyncratic popularizer of science, Pyke is a renowned expert on yeast and its various products. From 1973 to 1977 he was secretary and chairman of council of the British Association for the Advancement of Science, and for 18 years before that he was manager of the Distillers Company’s Glenochil Research Station in Scotland. His first book, dating from an earlier period as a government nutritional adviser, was his Manual of Nutrition (1945), but two dozen others have ranged widely, from Slaves Unaware and Automation, Its Purposes and Future, to Butter-side Up and Long Life. Pyke’s recreation, recorded in Who’s Who, is to “write a page a day and savor the consequences. He is equally proud of his many academic honors and his selection by the popular children’s television program as the BBC Multi-Coloured Swap Shop Star of the Year for 1977-78.

Muddled Thinking Is Hard to Swallow

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