I’ve been meaning to write this article for a while. I’m writing it now because we are starting to sell carnitas this week. In browsing around the web I found dozens of comments like, “Carnitas, they might shave years off of your life but they’re soooo delicious. Nonsense! They won’t shave anything.
Merck and Schering-Plough, the pharmaceutical giants, recently unwittingly pulled the last leg off of the stool that was supporting the house of cards that is the “lipid hypothesis”, the theory that eating saturated fat and cholesterol causes your “blood cholesterol” to rise which leads to a heart attack. The lipid hypothesis, also known as the diet-heart hypothesis, never really made sense and was never supported by the weight of the evidence. And now they’ve gone and toppled the whole thing.
Mind you, this thing has got a life of its own and its gonna take a while for the realization to sink in with the general public. But I’m calling it. The theory is now officially dead in the water.
Like I say, the lipid hypothesis never made sense. The epidemiological evidence never supported it, ie the French Paradox. It’s no wonder that all of the large studies on the subject have failed to show the anticipated results.
It’s always been known that in European countries such as France and Switzerland people eats lots of saturated fat and yet have low levels of heart disease. These days we could also throw countries such as Italy, Belgium, the Netherlands and Spain into that category. Conversely, the highest rates of heart disease in the world are in Eastern Europe in countries such as Russia, the Ukraine and Kazakstan where they eat comparatively little saturated fat. In Uzbekistan, the people eat only one quarter the amount of animal fat that they do in France yet die of heart attacks at six times the rate. If saturated fat consumption is the primary cause of heart disease, how can you explain this? Interestingly, although it is true that in rural China they eat very low fat diets and have low rates of heart disease, there are subpopulations in China that eat tremendous amounts of saturated fat but still have very low rates of heart disease.
Furthermore, there is no relationship between blood cholesterol and heart attack rates either, epidemiologically speaking. If you look at the graph here, you can see that the three countries (of the nineteen included on the graph) with the lowest percentage of people with high cholesterol are China, the US and Russia. China has the lowest levels of heart attacks, Russia has among the highest and the US is right in the middle. Switzerland has the highest percentage of people with high cholesterol – more than fifty percent – and among the lowest rates of heart attacks.
Given all of that, it is hardly surprising that large scale peer-reviewed diet studies have failed to show any benefit to a low saturated fat diet. The Nurses Health Study kept track of the dietary habits and health outcomes of 80,000 nurses for over twenty years and found no benefit to a low saturated fat diet. The The Multiple Risk Factor Intervention Trial (MRFIT) had men eat less fat, exercise more and stop smoking but had no effect on heart attack rates in the test group. The Women’s Health Initiative low-fat diet study showed that a low-fat diet does not prevent heart disease, cancer, or stroke, and that a low-fat diet does not aid weight . Other failed studies include the National Diet-Heart Study , the Los Angeles Veterans Administration Study and the Minnesota Survey . More recently, several studies have shown that the Atkins diet improves “good cholesterol” levels while leaving “bad cholesterol” levels unaffected.
Given all of this, it was a little baffling when the original studies on statin drugs – cholesterol lowering drugs such as lipitor – showed that they reduced heart attack rates. Now don’t get the idea that they will make you live longer; none of the statin studies have shown that. The small decrease in heart attack deaths are generally offset with higher rates of death from cancer and violence. But they do reduce heart attack rates. A little. In people who already have heart disease. Now why should this be?
We know that statins lower “blood cholesterol” levels and reduce inflammation. We also know that aspirin reduces inflammation and lowers heart disease risk by a similar amount to statins at a much lower cost. We know that the evidence connecting “blood cholesterol” levels to heart attacks is flimsy at best. So the logical inference is that statins work by reducing inflammation rather than reducing “blood cholesterol” levels. How can we know?
A Japanese study, J-LIT, was done to determine whether or not the reduction in heart attack risk from taking simvastatin was caused by reducing cholesterol levels. How? They split the test subjects into three groups: people whose “blood cholesterol” levels were not lowered by the drug, people whose “blood cholesterol” levels were lowered a little and people whose “blood cholesterol” levels were lowered a lot. There was no difference in heart attack rates between people whose cholesterol levels were unchanged and those whose cholesterol levels were lowered a lot. The two groups had final “bad cholesterol” levels of 200 versus 80 but the exact same rates of heart attacks. This is highly suggestive that simvastatin works by a mechanism OTHER THAN “blood cholesterol” lowering.
The Last Nail in The Coffin
Which brings us up to the present, or recent past anyway.
This January, Merck and Schering-Plough released the results of their ENHANCE trial that was supposed to show that their drug, vytorin, would reduce heart disease rates by more than Zocor. This is interesting because Vytorin is a combination of drugs, a statin and a new drug, that reduces “blood cholesterol” by two seperate mechanisms. This allows it to achieve significantly greater “blood cholesterol” reductions than a statin alone. In the ENHANCE trial, vytorin reduced “blood cholesterol” levels by 58% whereas zocor only reduced them by 41%.
Did vytorin work better than a statin alone? Of course not! That’s because statins work by a mechanism other than lowering “blood cholesterol”.
Don’t believe me?
That’s fine. You should check out:
Eat, drink and be merry! Don’t let the cholesterol cops run your life. The don’t have a leg to stand on. Be more like the French. They eat what they like and they don’t have heart attacks.