Rather than looking at the calorie content of food, it makes more sense to understand how food affects metabolism, weight gain and weight loss.

Eminent world-class medical scientists have recently expressed serious doubts about the reliability of so-called ‘evidence-based medicine’ on which dietary advice and pharmaceutical drug protocols have been based in recent decades.

The relatively new subject of epigenetics is beginning to explain how diet and lifestyle can change the way our genes work. There are two broad types of inheritance: single gene and multiple gene inheritance.

Single gene inherited diseases are relatively uncommon and cannot be altered to any significant extent by changes in diet or lifestyle. Multiple gene (multifactorial) inheritance is responsible for the common chronic diseases, many of which are serious, such as heart disease, diabetes type 2 and many cancers.

The genes of multifactorial inheritance can be ‘switched on’ or ‘switched off’ by changes in diet and lifestyle. Therefore, the old belief that you could not alter your health and longevity by changes in diet and lifestyle (because that was only determined by your immutable genes) is exactly that – old hat and wrong.

Medical fiction can become popular fact and, regrettably, the penalty for depending on unscientific data in the field of nutrition is obesity, diabetes, chronic exhaustion, heart disease and even cancer.

Does one need to increase their metabolism to lose weight? The answer is no. A slow metabolism does not make you fat

It may take a generation for new radical scientific advances to be accepted by mainstream doctors and the public. For example, it took at least 20 years for Robert Marshall, an Australian physician, to convince the medical world that, based on experiments upon himself and a colleague, together with trials on their patients, he had proven that peptic ulcer was caused by a bacterial infection of the stomach and was curable with antibiotics and not with surgery.

Mistakes are frequent in medical and nutritional practice but, due to our body’s resilience to illness, it often takes decades to see the ill effects of nutritionally bad foods. The current pseudo-scientific statements and recommendations may therefore put you and your family on the path to self-destruction.

Nutritional and pharmaceutical companies may mislead doctors and lay people while chasing profits. Medicine safety regulators in both the US and Europe, instead of invariably insisting on measurement of outcome directly, often allow the use of ‘surrogates’ to prove future outcomes.

For example, there is an assumed relationship between lowering blood cholesterol and decreased heart attacks, although this is not really backed up by good science. While drug companies have done a wonderful job discovering cholesterol-lowering drugs, this hasn’t translated into significantly fewer heart attacks.

Yet it has become ‘conventional wisdom’ and practice to reduce patients’ LDL cholesterol in order to reduce heart attacks. Drug companies do not have to prove that the person taking their latest ‘wonder’ drug will live longer, or that the drug is safe to take on a long-term basis.

The naïve ‘calorie theory’ of obesity has recently been quoted as an example of the incorrectness of ‘conventional wisdom’. For decades we’ve been told that calories consumed minus calories expended equals amount of weight gain or loss. But many nutritionists and doctors have an incomplete understanding of how food is used in our body.

Each of the three different food groups, carbohydrate, fat and protein, has a different role in the body. Most nutritionists believe our body acts like a heat engine, burning everything we eat like wood in a fireplace.

Calorie theory proponents ignore the fact we eat for structure – making muscles, organs, hormones, enzymes, antibodies and bone – not merely to generate energy by ‘burning’ food. The body is more a chemical factory, not a heat engine.

In 2003, the Harvard School of Public Health found people on a low carbohydrate diet could consume 25,000 more calories than those on a high-carbohydrate diet and, at the end of the 12-week study, gain zero pounds. Penelope Green, the director of the study, was mystified and admitted that this finding strikes at one of the most revered beliefs in nutrition: “a calorie is a calorie.”

Therefore, rather than looking at calorie content of food, it makes more sense to understand how a food affects metabolism, weight gain and weight loss – this is the food’s ‘utilisation factor’.

Does one need to increase their metabolism to lose weight? The answer is no. A slow metabolism does not make you fat. If your metabolism increases, you’re hungry all the time. A fast metabolism is not the answer to becoming and staying lean.

To become lean, one needs to stay on fat-burning mode longer, yet not have to eat all day long. We’ll discover in a future article how to stay full and content all day while your body is in fat-burning mode, even while you sleep.

Prof. Cilia-Vincenti is a practising pathologist, a scientific delegate to the European Medicines Agency and a chairman of the Academy of Nutritional Medicine (London). He is a former lecturer at London and Malta universities.