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The debate about cholesterol is confusing and contentious. Confusion lies at its heart because there are two kinds of cholesterol: ‘good’ and ‘bad’. High density lipoproteins (HDLs) help to protect against heart disease, so they are known as good cholesterols. Low density lipoproteins (LDLs) may increase the risk of heart disease: these, then, are the bad cholesterols. But it is to be remembered that cholesterols, both ‘good’ and ‘bad’, are essential to the proper functioning of every cell in the body, and we derive them almost exclusively from animal foods. The catch seems to be that we can have too much of a necessary thing. We need cholesterol to live, but if we ingest too much of the ‘bad’ cholesterol then, according to the nutritional experts, we die.

It seems obvious that if we eat a diet rich in animal foods we will inevitably increase our cholesterol intake, including, of course, the villainous LDLs. But is that true? The October 1995 issue of the Canadian Journal of Cardiology is clear on the issue: ‘Analysis of the results from over 30 years of cholesterol feeding studies in more than 2,750 patients indicates that for the majority of individuals modest changes in dietary cholesterol have little if any effect on plasma lipoprotein cholesterol levels.’ So a modest increase in the consumption of animal fats will have little if any effect on most people’s cholesterol level. Matters are made more confusing by the conclusion of a report in the Mayo Clinic Journal which reads: ‘The total cholesterol level is a relatively weak marker for the risk of coronary heart disease.’¹⁰ What these professional journals appear to be saying is that too much weight is placed on cholesterol levels and that the link between such levels and coronary heart disease has been exaggerated. Cholesterol was once reckoned the major coronary villain, now it is blamed in only 20% of heart attacks.¹¹ Fear is created that is either out of proportion to the risk or, when the risk exists, out of proportion to our ability to lessen the risk. The cholesterol card is too easily and too often overplayed.

Analysis of two decades of cholesterol-lowering studies has failed to show a related decrease in total deaths.¹² The most recent Scandinavian study on the effects of lowering cholesterol with drugs had too few deaths to show any significant reduction in total mortality.¹³ Some other recent studies do show more favourable results from cholesterol-lowering drugs,¹⁴ but it is also argued that yet more studies are needed if these results are to be accepted as conclusive.¹⁵ The scientific jury is still out, so while we await the verdict it is instructive to learn of some findings by David Barker and his team at the Medical Research Council’s Environmental Epidemiology Unit at Southampton. In a study of 6,500 men they found that a man’s weight at one year old was a far better predictor of death from heart disease than his cholesterol level within a year or two of his death.¹⁶

The case against cholesterol, or specifically against LDLs, is unproven, but a prudent person might prefer to accept that LDLs are indeed dangerous and so avoid those foods which are high in them. Which, surely, means avoiding red meat? But is the bad cholesterol that results from eating beef really any worse than the bad cholesterol found in chicken? That is what 13 Texan researchers investigated in 1991¹⁷ when they checked the good and bad cholesterol levels of 46 men given differing diets. Employees and students from the Texas Medical Center, Houston, were first fed a ‘stabilization diet’ of regular prime beef (13.6% fat) for four weeks. They were then divided by lot into two separate groups and for the next four weeks one group was fed with lean top round and loin steaks (both containing 4% fat) while the second group was fed chicken breast and red snapper (both containing 1.7% fat). The rest of the diet, vegetables, fruit, drinks, etc, were the same for both groups.

The researchers discovered that ‘changes in total cholesterol and LDL [the bad cholesterol] were similar in the two diet groups … percentage decreases in HDL [the good cholesterol] also were greater in the chicken and fish diet group than in the lean beef group.’ In other words, the men who ate the beef had more good cholesterol at the end, and the same amount of bad cholesterol, as those who were forced to eat chicken and fish. Other studies also show that diets with lower levels of fat cause HDL, the good cholesterol, to decrease.¹⁸ So the result of the Texas Medical Center study flies in the face of common prejudice: the beef eaters had the better cholesterol profile.

A recent experiment shows that low fat diets increase anger and hostility and makes people more depressed – and that a low fat diet had no total effect on cholesterol. A team led by Dr Anita Wells at the Centre for Human Nutrition at the University of Sheffield studied two groups of men and women. The volunteers spent a month eating a diet in which 41 per cent of the energy came from fat – a typical British diet level. Then for another month, half were given a diet with only 25 per cent fat – slightly lower than the health department’s ‘healthy eating’ guidelines. The result: the ‘good’ form of cholesterol, which protects people against heart attack, declined, while the bad form showed no change – meaning that the low fat diet may actually increase risks in this case. Dr Wells concludes: ‘Everyone says that eating low-fat diets will cut cholesterol, but the science doesn’t demonstrate it.’¹⁹

Response to a low-fat diet may depend entirely upon a person’s genes. Dr Ronald Krauss of the Lawrence Berkeley National Laboratory, California, told the American Association for the Advancement of Science in March 1998 that very low-fat diets reduce heart-attack risks in only a third of the people who adopt them. The rest — two-thirds of men and five-sixths of women – fail to respond to the diets, or may even ‘suffer increased risks because of the genes they carry’.

‘It seems,’ says Anne, ‘that the less-and-less important the intake of cholesterol becomes, the more-and-more important it becomes to cut its intake.’

‘That follows,’ says Bill. ‘To the degree its intake is found harmless, or meaningless, so it is safer to manipulate its intake.’

So the science does not condemn red meat in the diet – indeed, it appears to endorse it as a means of raising good cholesterol levels. If only it were that simple, for even more recent research introduces yet another level of uncertainty. Dr Ronald Krauss has found that the response to a low fat diet depends on the dieter’s genes. Dr Krauss has further divided LDL, the ‘bad’ cholesterol, into two kinds and he finds that about one-third of men and about one in five or six post-menopausal women have what he calls Pattern B LDL,²⁰ and it is this pattern B that does the damage. So the minority of people who possess Pattern B LDL do benefit from a low fat diet, while the rest, the majority, do not. Indeed, if people without Pattern B LDL go on a low fat diet, they run the risk of converting their harmless Pattern A LDL into the deadly Pattern B.

This book cannot be the place to resolve the continuing debate over cholesterol and its effects, but we can note that there is nothing in any of these scientific studies to confirm the nutritional world’s condemnation of meat. Eating red meat does not increase your levels of LDLs and does increase your HDLs, so if cholesterol is your beef, then the dangers have been hugely overestimated while the benefits of red meat have been played down. Not only is red meat a splendid source of protein and micro-nutrients, it confers other blessings. Dr Richard Petty of the WellMan Institute in London has been monitoring men who have switched from red meat to white, and his study discovered a significant decrease in haemoglobin, the blood component which carries oxygen from the lungs to the muscles. For men who insist on avoiding red meat the WellMan Clinic prescribes iron and Vitamin C in an attempt to restore their fitness.²¹ Simpler to eat beef, perhaps?

But what about fat? Not cholesterol, but nasty, horrid, artery-blocking fat? If there is any one popular diet certainty then it is that we should all cut our consumption of fat, so surely we should be refusing red meat?