Sunday 11 March 2007

Are Our Healthy Eating Guidelines Wrong?

Obesity, diabetes and heart disease are among the major scourges of the western world. Medical science, although to some degree able to treat these conditions, has so far failed miserably in terms of prevention. Incidence rates are openly acknowledged as having reached 'epidemic' proportions.

It is generally accepted that diet is the main cause, but opinions vary as to which particular aspect of diet is at fault. The conventional belief is that a high intake of fat is the culprit. Accordingly, healthy eating advice in much of the western world is focused first and foremost on reducing fat. Subsidiary messages include increasing fiber, vegetables and fruit and taking around fifty to sixty per cent of daily calories in the form of carbohydrate. But how valid is this advice?

Evidence is mounting that the healthy eating advice we have been following over the past few decades is metabolically wrong for the majority of the population and that carbohydrates rather than fat are the real villains.

Some fats are indeed injurious to health but new understanding shows that saturated fat has been wrongly accused of the misdeeds of the true 'bad' fats -- fats called trans fats or hydrogenated fats and oils. There is also general recognition now that certain fats are essential for health -- the essential fatty acids (EFAs). In fact, many of us are actually deficient in a type of essential fatty acid called Omega-3. This has been caused in no small part by the 'fat phobia' of the past decades.

When it comes to obesity, a high fat intake may well contribute to excessive calorie intake but calories are not the whole story. Some of us are better than others at storing any surplus energy as body fat. In our caveman days our energy storage mechanism was what kept us alive from one infrequent meal to the next. Nowadays however, our food is plentiful and our storage mechanism, namely the hormone insulin, is not quite so useful. Not only do lean times come rarely, if ever, but we burn off ever less physical energy in our daily activities. Furthermore, our food is much higher in carbohydrates -- cavemen did not have refined foods such as the sugar and flour that are our staple foods today. These foods cause our blood sugar levels to rise faster, higher and more frequently than our control system was designed to handle. This results in a constant outpouring of insulin. For many this creates a blood sugar imbalance, which traps them in a vicious circle of eating, feeling hungry and eating again regardless of whether more food is needed.

By process of evolution we might expect to become genetically adapted to a diet high in refined carbohydrates, but this would take millions of years rather than the few decades that we have been eating this way. In the meantime, those who lay down fat in response to today's food are only being more efficient than the rest at doing what they are genetically programmed to do. For this group, a carbohydrate-rich diet is almost bound to cause obesity. Even a diet emphasizing 'healthy' carbohydrates such as whole grains and fruits may be too high in carbohydrates for some. Since it is estimated that this carbohydrate-sensitive group comprises up to sixty per cent of the population, and it is precisely this group that is likely to be obese, reducing fat intake and basing the diet on carbohydrates is more likely to exacerbate the obesity problem than to solve it.

Weight gain is not however the only consequence of this imbalance in our blood sugar control systems. Years of insulin overproduction are likely to be followed sooner or later by insulin resistance and ultimately, type 2 diabetes. Furthermore, there is evidence that it is these constantly high levels of insulin, and not dietary fat, that cause heart disease.

For instance, in December 2002, researchers at Harvard School of Public Health published a study of the diets of more than 100,000 people in the American Journal of Clinical Nutrition. The study had come to the totally unexpected (for some) conclusion that those who did not follow the US healthy eating guidelines lowered their risk of chronic disease by around thirty-five per cent. Dr Walter Willett, chair of the department of nutrition at Harvard, stated 'The public has been told for many years that fats are bad and carbohydrates are good. In fact, we've known for thirty or forty years that that's not really true.'

One of the most respected researchers in the field, Dr Willett also declared in articles in Obesity Review and the American Journal of Medicine: 'Dietary fat is not a major determinant of body fat and plays virtually no role in obesity.'

So if science is showing us that the root causes of the current obesity, diabetes and heart disease epidemics are not what we formerly thought, why aren't the medical world and government health departments rushing to change the healthy eating advice they promote?

Many think the answer to this question lies in conservatism, bureaucracy and vested interests. The first issue to recognize is that the new scientific concepts take more than a little time to explain and understand. Medical professionals are busy people and have little time to devote to new topics. The spread of new ideas is also inhibited by factors such as the average overworked physician's understandable reliance on drug company representatives for information on new research. The general conservatism of the medical world may also play its part in the slow recognition of the new ideas. The position is not helped by the fact that, until now, basic medical training has virtually ignored the topic of nutrition, and postgraduate courses recognized by the mainstream medical establishment are only now being established to teach this unjustly neglected area of medicine.

Slow pace of change in health policy at governmental level is inevitable. New diagnostic and treatment methods are required to go through many years of population studies and clinical trials before they are approved for general use. Moreover, state funding for such studies is limited and the research done by the commercial drug companies focuses, not unsurprisingly, on areas of research that will make them money. In other words, in the current environment nearly all research that is done is targeted at identifying block-busting drugs that can make decent returns for the pharmaceutical companies. Researching unpatentable diet and lifestyle solutions which address the root cause of illnesses is not economically viable for the pharmaceutical industry.

Added to that, the pharmaceutical, agricultural and food manufacturing industries have vested interests in the existing carbohydrate-focused, fat-phobic healthy eating advice. Since they have an extremely powerful voice with government, this no doubt also serves to put a brake on major governmental policy change in the area of healthy eating guidance.

With all these factors acting to slow the pace of change as far as healthy eating advice is concerned, it seems clear that it is up to individuals to take responsibility for their own health. Putting blind faith in official healthy eating advice seems a risky strategy.

More information on these concepts can be found in the e-book Why Can't I Lose Weight -- The Real Reason Diets Fail And What To Do About It.

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