Blood clots?

There is another theory which has  nothing to do with cholesterol or fat in the diet, but does explain how blood clots lead to heart attacks. 

Some doctors and scientists have not been completely bludgeoned by saturated fat hysteria and their research has discovered things in our blood called pre-endothelial cells.  These are produced by our bone marrow, and travel about the blood stream in their billions looking for breaches in the artery walls. Their job is to prevent arterial clots reaching too big a size.  If a blood clot has got there first, they cover the clot entirely and transform themselves into new artery walls (the medical name for an artery is endothelium).  Usually they are then broken down and the artery wall is as good as new.  

The theory advanced by scientists at Duke Health.org is that as we age, our bone marrow produces less of these cells, so repair to arteries is slowed down, hence why we are more prone to heart attacks when older.  

Sadly that link just leads us to the hospital now, so here is a  link to a research paper about the same topic, but positing ways of healing damaged arteries: http://hyper.ahajournals.org/content/46/1/7.short  

With repeated damage to the artery wall, new clots form over the existing ones and slowly large plaques build up.  These will either block the artery or break off and trundle through the artery until they reach a narrow point, where they lodge and cause either a heart attack or stroke.

This is one of the mechanisms that statins are effective at dealing with. To prevent over formation of blood clots following a heart attack or stroke, anti-clotting medication is prescribed, eg aspirin, warfarin, ACE inhibitors and statins. But in a situation where LDL cholesterol and saturated fat are reckoned to cause heart attacks, many doctors call for everybody over 50 to be taking a statin for its cholesterol lowering abilities.  The trouble is that cholesterol is not the cause of the problem.

Incidentally, it is also the anti-clotting ability of alcohol that gives one of the health benefits of moderate drinking.

To reiterate, arteries are not physically clogged up by eating lard – they are clogged up by scabs on damaged arterial walls 2 .  Returning to the assumed fact that eating saturated fat pushes up cholesterol levels, even Ancel Keys, father of the low fat myth, said:

There’s no connection whatsoever between cholesterol in food and cholesterol in blood.  And we’ve known that all along.  Cholesterol in the diet doesn’t matter at all unless you happen to  be a chicken or a rabbit.  Ancel Keys, PhD, Professor Emeritus at University of Minnesota, 1997.3

So what is the basis for this myth? 

Well, the reason Dr Keys referred to rabbits is due to the amusing beginning of research linking saturated fat to heart attacks.  An 18th Century  Russian researcher, Dr Nikolai Anitschkov, fed rabbits a high cholesterol diet – full of the dreaded animal fats. And indeed their arteries did thicken and fill with cholesterol, and so the myth that saturated fats lead to increased cholesterol levels was given life.  

Of course, it is another well known fact that bunny rabbits are not lard eaters –  it wasn’t Mr McGregor’s lardy thighs that Peter Rabbit was after – but Mr McGregor’s lettuces.  In fact, what Dr Nikolai Anitschkov proved is that eating a diet that is very wrong for us raises our cholesterol levels.  There is no doubt that this would happen, as one of the many good things cholesterol does for us is lower inflammation in the body, and raised levels indicates there is serious inflammation going on somewhere.  If we eat a diet full of transfats, rancid fat, highly processed and refined foods, this is highly unnatural for us and ultimately makes us ill.  But to blame raised cholesterol is like seeing many fire engines driving past.  The next day huge devastation is found some miles from where we live – so therefore the fire engines, making all that dee dah noise, must have caused all that damage.  So excessive chip consumption will not do our arteries any good at all.  However there is another culprit, and that will be explored in another blog: stress.

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