The Great Cholesterol Con

[Guest guest]

The following can be found on this blog For something that hardly anyone had heard of 20 years ago,

cholesterol has become something of a phenomenon. We are encouraged to

keep a lid on our cholesterol levels – the recommended amount of which

in the blood seems to be in perpetual decline. And this is there is

quite a lot of political pressure put on individuals to bring their

cholesterol levels into line. This week, for instance, saw the

publication of a report which highlighted the fact that only 47 percent

of women with a history of heart problems had their cholesterol `under

control', compared to 56 percent of men. Tut tut.

Despite our collective neurosis about cholesterol, there is a

considerable body of evidence to suggest that this fat is not the

killer it is so often made out to be. While there is indeed some

evidence that high cholesterol levels are associated with an increased

risk of heart disease and death, a close look at the available evidence

shows that this association only seems to be true for individuals up to

the age of about 50 or so. After that time, plenty of evidence shows

`raised' cholesterol levels in later life are not associated with

adverse effects on health [1-15]. Indeed, there is even some evidence

that higher cholesterol is actually associated with enhanced longevity

and survival [16-19].

Now it's worth bearing in mind that the vast majority of cases of

conditions said to be related to raised cholesterol levels (namely

heart attacks and strokes) occur in middle age and beyond. As the

science shows that cholesterol is not a risk factor, and indeed may

even be beneficial, in people of this age, then this should perhaps

cause us to question the current appetite to paint cholesterol as the

culprit.

As with saturated fat, if we really want to make a judgment of the

true impact cholesterol has on health, we need intervention studies –

studies in which cholesterol levels are lowered and the effect of this

assessed. In 2005 a meta-analysis which combined the results of 17

similar studies in which subjects made dietary changes explicitly to

reduce blood cholesterol levels was published in the Archives of

Internal Medicine [20]. Overall, these studies brought about a 10 per

cent lowering of cholesterol levels. Despite this, the amassed results

showed no reduced risk of death, neither in healthy individuals, nor

even in high-risk individuals who had a history of heart attack or

stroke. Basically, taking dietary steps to reduce cholesterol levels

simply does not seem to save lives – yet more evidence that cholesterol

is not as important a factor in health as it is so often said to be.

Apart from diet, the other major way to quell cholesterol levels is

through drug therapy. Currently, the most popular type of medication

used for this purpose are known as the `statins' which include

atorvastatin (Lipitor), rosuvastatin (Crestor) and simvastatin (Zocor).

A huge stash of cash has been made out of these drugs, but is their

life-saving reputation deserved?

Statins do seem to have the capacity to save lives, though the

benefits of them seem to be largely confined to individuals who already

have diagnosed cardiovascular disease (e.g. heart disease or previous

stroke). This evidence is often used to support the notion that

cholesterol causes heart disease. However, in additional to reducing

cholesterol, statin drugs also have other effects in the body that

would be expected to reduce the risk of cardiovascular disease. For

instance, it is well recognised that statins have anti-inflammatory

effects, and current evidence suggests that inflammation is an

important underlying process in the development of cardiovascular

disease. This has raised the question that statins' apparent ability to

reduce the risk of cardiovascular disease may have nothing at all to do

with cholesterol.

I suppose this wouldn't matter too much if the recommendations to

lower cholesterol upper limits were based on good science. However, a

review in the ls of Internal Medicine published in 2006 concluded

that there was no high-quality clinical evidence to support current

treatment goals for cholesterol. The authors of this review went on to

say that the recommended practice of adjusting statin dose to achieve

recommended cholesterol levels was not scientifically proven to be

"beneficial or safe" [21].

It is perhaps interesting to note that the most recent

recommendations regarding cholesterol levels in the USA came from a

panel of nine scientists, eight of whom had financial links with drugs

companies making statin drugs. And this clear conflict of interest only

emerged after their report had been published.

It seems that the impact of cholesterol on health might have been

seriously overstated. For those of you keen to learn more, I heartily

recommend to you a The Great Cholesterol Con by British medic Malcolm

Kendrick. Read it, and I reckon it's unlikely that you may find the

interest in your cholesterol and any fear you have about this wanes

somewhat.