Identify the enemy, label and demonise him. A reputation destroyed is mon-umentally difficult to rehabilitate. We are not talking politics here; we are talk-ing nutrition. Cholesterol, as everyone knows – or believes – is a killer. A high blood cholesterol is an ominous finding, and in many information sources on the internet you will find advice (usually Bupa-sponsored) about how to lower it through dietary changes and medication. The implication is that you will thereby lower your risk of a heart attack or other cardiovascular event, and your chances of dying from the same.
The evidence for this, however, consists of a bunch of plausible theories, some political zealotry, a few dizzying leaps of faith over the gaps that were too expensive to check, and a lot of propaganda. There is plenty of evidence to show that cholesterol is not a heart poison as portrayed, but somehow this does not percolate into the public’s perception.
Coronary heart disease is a plague of affluent countries. In Britain and the US the rates began to rise in the 1920s, climbing steadily for decades to become the greatest single cause of death. Sudden death in young men caused particular alarm. Heart attacks are caused by the narrowing of the arteries that feed heart muscle by a porridgy substance called atheroma, a fatty lump rich in cholesterol. Thus this steroid-like chemical came under suspicion, even though the substance is integral to all cell membranes and the precursor of adrenal steroids and sex hormones; and virtually all circulating cholesterol comes from the liver, not the diet.
But the argument grew that dietary fats in general and cholesterol in particular caused heart attacks. Vast sums of money were spent on trials designed to show that adjusting diets to lower blood cholesterol would lower the risk of heart attacks. Alas, the research did not come up with the expected results. Cholesterol levels did not drop as expected; heart-attack rates were not reduced.
But then, in 1984, a trial showed that lowering blood cholesterol by means of a drug (cholestyramine) would indeed cause a minuscule lowering of heart risk. The myth that ischaemic heart disease could be prevented by dietary manipulation in all people (not just at-risk middle-aged men taking drugs, as tested in the trial) was born. It was spread and perpetuated by a concerted publicity campaign.
In the UK, instead of going to work on an egg, we were told that even one roast joint and three eggs a week could be our cardiac nemesis. Everyone was encouraged to limit butter, cream and animal fats, and to eat vegetable fats and margarine instead. In the US, if you tried to protest and say something positive about cholesterol in a science meeting, you could have your research funding stopped.
Though deaths from ischaemic heart disease are dropping in the UK, actual incidence continues to spiral. The alarming premature death rates in young men declined rapidly after 1965, well before large-scale dietary change. The curious paradox is that, although it is a disease of affluence, deaths from it are higher among poor people. Comparisons between coun-tries, cultures and sub-groups, as well as cohort analysis, suggest strongly that the cause lies in some bad experience in infancy, perhaps conditioning by ultra-poor nutrition back then. The association with adult diet is absolutely unproven.
The market for statin (cholesterol-lowering) drugs is flourishing on misinformation. There is ample evidence that they may lower death rates from heart attacks in some people, but cause damage in other systems, and possibly deaths from other causes. Recognised dangers are memory loss and mental confusion, increased risk of breast cancer in young women, liver disease and heart muscle damage by interfering with the all-important enzyme CQ10.
This is hardly surprising, given cholesterol’s fundamental role in the body’s chemical workings, and its huge importance as a component of brain tissue. Cholesterol has a role in enhancing immune function, and a raised level seems to be beneficial in the elderly. Clinical trials on drugs must have a narrow focus to germinate results, an approach which works conveniently for companies sponsoring their own statins. They go looking for the benefits of lowering cholesterol, to the greater glory of their product and their profits. The downside – damaging effects – is none of their business.
The truth about what constitutes a good diet tends to change with each generation, and is confounded by growing knowledge as well as vested interests – commercial, political and medical. No one likes to admit they were wrong. At a time when statins are available over the counter without prescription – absolutely wrongly for a long-term, supposedly preventative, medicine – people need to know the truth. It is time for cholesterol to be rehabilitated as a chemical vital to functioning – one that we adjust too radically at our peril.