Sun, Aug-28-11, 02:18
Big fat lies
From The Sunday Times
28 August, 2011
Big fat lies
Everybody knows sausages are fat-laden torpedos of death. But what if they don’t clog your arteries? What if cholesterol isn’t bad for you after all?
T he offer of sausage, bacon, black pudding and fried eggs, which — with lashings of buttered toast or fried bread — used to be the nation’s traditional breakfast is now confined largely to hotels. Why? Because it is full of the saturated animal fat that raises cholesterol and clogs the arteries, with serious consequences for your health. The hearty banger has been recast as a cholesterol-packed enemy agent.
Yet the received wisdom about cholesterol is being challenged. Now it appears that, as with so many diktats about diet, the evidence is not so clear cut. New research suggests we have been misinformed about the risks and benefits of cholesterol, in much the same way that recent evidence indicates salt might not be so bad for you after all; sugar might not make you as fat as artificial sweeteners; and extra water may not produce health-giving “superhydration”.
A growing body of scientists is questioning the theories that cholesterol levels are related to animal fat intake and that it causes heart disease. These critics claim blood cholesterol levels are principally set by your genes, but can vary wildly from one blood test to the next for no apparent reason. They point out that the French and Swiss have higher levels of cholesterol than we do, but far fewer of them die of heart disease. Nobody has ever explained the mechanism that converts the animal fat you eat into cholesterol, or, despite what cardiologists would consider to be obvious associations, even proved the role of cholesterol in heart disease. Meanwhile, a paper published recently in the journal Archives of Medical Science points out that animal studies have shown that it is fructose that is converted into cholesterol in the liver, not fat.
Westerners are eating ever-greater quantities of fructose; it is cheaper than normal table sugar (sucrose) and sweeter. Most people think it is healthier because it occurs naturally in fruit and honey. In fact, most of our fructose intake comes from the artificially extracted and manufactured versions included in virtually every kind of processed food. These are made from maize and metabolised in a different way from sugar.
Cholesterol is a fatty substance in the blood.
It is present in some foods, including eggs and shellfish, but is mainly produced in the body by the liver.
We need it for cell formation, nerve insulation and hormone production. In Britain, it is measured in units called millimoles per litre of blood, and the average cholesterol level is about 5.5mmol, which some think is too high.
Although cholesterol is one of the components of the lumps of “gunge” that obstruct diseased arteries, there is a continuing argument over whether it is a primary cause or a secondary invader, following on from some other inflammatory process.
While it is accepted that very high cholesterol — upwards of 9mmol —makes the blood too sticky and is definitely dangerous, but other research shows slightly higher blood cholesterol, of 6mmol or more, may be associated with lower death rates from cancer and heart disease.
A debate on these findings, and whether we need to revise the advice on meat and dairy food consumption, has been organised by the Society of the Chemical Industry (SCI) for September. Malcolm Kendrick, a senior GP and contributor to medical journals, will argue at the event that virtually all the received wisdom about diet, cholesterol and heart disease is nonsense.
“Nobody has ever explained how this process works,” he says. “People with higher than average cholesterol actually tend to live longer. France and Switzerland have the highest level of cholesterol in Europe, but the lowest levels of heart disease. The Japanese have completely changed their diet in the past 50 years. They eat about four times more fat than they used to. Their cholesterol levels have gone up marginally, but their rate of heart disease has fallen by 50%. None of the argument stacks up.” Although he agrees heart disease and strokes are caused by “plaque” build-up on the artery walls, he thinks this is caused by high blood sugar, stress hormones, cell damage, diabetes and old age.
Bruce Griffin, professor of nutritional metabolism at Surrey University, who is opposing Kendrick in the debate, says that just because not every person with raised cholesterol drops dead from a heart attack, it does not meant cholesterol is not a risk factor. “The scientific and clinical evidence supporting the relationship between raised cholesterol in the blood and heart disease is beyond dispute,” he says. However, he acknowledges that other unidentified dietary components may reduce the cholesterol-raising effect of saturated fat, and he adds: “The majority of people with raised blood cholesterol do not develop heart disease because the process of the disease is complex. It depends on many other factors, such as age, gender, being overweight or obese, having raised blood pressure and family history.”
Meanwhile, Uffe Ravnskov, a Danish doctor presiding over the International Network of Cholesterol Skeptics, is in no doubt that the widespread acceptance that cholesterol is bad for you has been brought about by a pharmaceutical industry intent on getting everyone over 40 onto statins. This group of products, proven to reduce blood cholesterol levels, is already the industry’s biggest money-spinner, even outselling Viagra. There is a constant drive to maintain the conviction among GPs that statins delay death — and to reformulate their ingredients to maintain patent protection. “Medical journals are dependent on drug companies for finance, so they are usually reluctant to publish anything that suggests drugs don’t benefit people,” Ravnskov says.
Earlier this year, the respected Cochrane Collaboration in Oxford reviewed and reanalysed the scientific research on statins, giving some ammunition to Ravnskov’s claims by declaring that decades of use have proved that statins do not increase overall life expectancy and only reduce heart attacks in people with pre-existing symptoms. Apart from the considerable cost of prescribing them to healthy people, the risk of side effects, which can include debilitating muscle wastage, outweigh the benefits.
The British Heart Foundation is sitting on the fence. “While it’s true cholesterol doesn’t directly cause heart disease, it’s an important link in the chain and one we should all aim to keep under control,” says Natasha Stewart, a senior cardiac nurse at the charity. “Having too much cholesterol in your blood can cause fatty deposits to form in your coronary arteries, and this may result in a heart attack.”
Laura Wyness, a nutritionist from the British Nutrition Foundation, points out that we need fat because it contains vitamins and fatty acids essential for body maintenance. “There is more to heart disease than just cholesterol,” she says. “Other factors such as high blood pressure and raised levels of other blood fats called triglycerides also increase the risk of heart disease. Different types of fats have different effects on blood-cholesterol levels and risk of heart disease, some beneficial and some adverse.”
The consensus, then, is if you are otherwise fit and healthy, cholesterol could kill you, but it probably won’t. So, who’s ready for breakfast?
10 ways to protect your heart
Here are some easy ways to cut the risk of heart disease
• Being fat raises blood pressure, which increases the risk of heart disease.
• Eating too much fat makes you fat, regardless of what it might do to your cholesterol, and the same applies to sugar.
• The more you exercise, the more your “good” HDL cholesterol goes up. HDL transports “bad” LDL out of the bloodstream and back to the liver.
• Unless you have a pre-existing heart disease or a high risk of developing it, taking statins to lower your cholesterol is unlikely to make much difference to your health.
• Lay off drinks sweetened with fructose or sugar substitutes. They are incredibly sweet and can “corrupt” your palate, making you crave sweet flavours.
• Eating oily fish twice a week or taking an omega-3 fish-oil supplement is recommended if you have heart disease, and it might help prevent it.
• Avoid rage. The odd temper tantrum will not make much difference, but there is evidence that permanent Basil Fawlty-type stress and anger increase the risk of heart disease.
• Don’t get drunk too often. It raises your blood pressure, which puts strain on your heart.
• Take up yoga or meditation — relaxation exercises reduce stress and lower blood pressure.
• Give up smoking.