Cholesterol is bad for you
That doesn’t sound like a very interesting headline, but an important clinical trial whose results were released today has made definite steps towards re-convincing researchers on this point.
The trial, IMPROVE-IT, looked at adding a new drug, ezetimibe, to one of the standard statin drugs for cholesterol lowering, in people who had previously had a heart attack. Ezetimibe works by blocking cholesterol absorption in the gut, a completely different mechanism to the statins, which block cholesterol synthesis. The drug had previously shown unconvincing results in a preliminary study, made even less convincing by the behaviour of the manufacturer. There was increasing uncertainty that the cholesterol-lowering effect of the statins was really how they prevented heart disease, since no other drug appeared to be able to do the same thing.
Now, IMPROVE-IT has found a reduction in heart attacks and strokes. It’s very small — only 2 percentage points, even in this high-risk group of patients — but it looks real. Given the price of ezetimibe it probably won’t be widely used immediately, but it comes off patent in a few years and then use might spread a bit. The results are also encouraging for dietary approaches to lowering cholesterol by reducing absorption: some cereals, and spreads with plant sterols.
Other stories: Forbes, New York Times
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »
Interesting. However, I’m not sure I agree with your headline. I think there’s a difference between saying “cholesterol is bad for you” and saying that blocking cholesterol absorption has an effect in people who are already identified as having issues with lipid processing. Perhaps cholesterol could actually even provide benefits to people whose bodies are better at dealing with it (e.g. because have insulin levels under control, exercise or whatever). Does this sound reasonable?
9 years ago
At some level it definitely provides benefits: eg cholesterol is a component of cell membranes and is also used to produce bile salts.
On the other hand, most non-vegans have LDL cholesterol levels in the range where higher levels are correlated with higher heart disease risk, and these trials provide additional evidence that the correlation is quite likely to be causal.
9 years ago
Sure, I guess I was wondering about confounding factors. If I have bacon, eggs & a stack of pancakes for breakfast then reducing cholesterol absorbtion will probably be a good thing because from what I hear the combination is not so good. But if I replace the pancakes with veges then I’m not so sure that this dietary cholestrol intake will have a negative effect on LDL. So its not that cholesterol is always ‘bad’, just when another some other factor is present… (I’m thinking back to this one – https://www.statschat.org.nz/?s=egg+yolk).
P.S. Great blog – I’m an avid reader.
9 years ago
I’m spooning cold pressed coconut oil in my mouth for a snack now.
Its a complicated area, in that boiled meats, gristle, bone and tendons[casseroles and stews], are [wisely]considered superior to lean cuts of fried muscle flesh.
Boiling keeps temperatures lower than frying, which alters the chemical structure by much higher temperatures.
Gristle has 2 amino acids necessary for liver detoxification, that the body does not produce, nor lean meat does not provide.
The politics of fat has its roots in medical profiteering.
Since the low fat Twiggy era of size zero women, autisms, ADHD and other brain disorders are on the increase.
The brain needs cholesterol. The white papery meat of tendons/cartilage, and also lung tissue is built mostly of cholesterol.
“Autoimmune responses – when the body attacks its own tissues. … These block cholesterol which the nerves are made of. …. the lower legs and feet, gait abnormalities, loss of tendon reflexes, and numbness in the lower limbs . … periods of multiple sclerosis activity, white blood cells are drawn to regions of the white matter”
Vegans quite often suffer from MS.
Northern Sami people eat [boiled] reindeer for breakfast lunch and dinner, especially the marrow. Apart from a small elevated risk of stomach cancer, they live healthy long lives, as long as they stay off the bottle.
9 years ago