Like a broken record, tales of cholesterol appear and submerge on an irregular schedule. I have in my files an old cartoon of a patient addressing her doctor, "Are you a cholesterol-is-all-bosh kind of doctor?" I certainly do not fall into that category. Cholesterol is hugely important, more important than all of the media hype that swarms about it, mostly uninformed.
The human body contains about 150 grams of cholesterol. Its presence is critical to many body functions including sex hormone production. Population studies reveal extensive variability in blood levels as low as 77 in the Bantu to as high as 280 and above in Western populations. Ancel Keys studied the serum levels in Japanese persons living in Japan, Hawaii, and the mainland U.S. He concluded that the closer the diet comes to the American average the higher is the blood level. (1) Stress also raises the level. Accountants at tax time and students at exam time have high levels.
But it is the dietary factors that keep resurfacing. Years ago when I was in my cholesterol experimental era I wrote a paper called "THE PATHOGENESIS OF HYPERCHOLESTEROLEMIA" in the Annals of Internal Medicine (2). It included studies that declare that the level in our blood depends not so much on the amount of cholesterol in the diet. Of much greater significance is the amount that is made by the liver. Whereas all body tissues contain the enzymatic machinery to manufacture cholesterol it is the liver that is the main source, about 1 gram per day. This makes much sense since the liver makes the bile that is essential to assist in the amount of fat that is absorbed. Bile is a byproduct of cholesterol metabolism, so it follows naturally that the more fat we eat the more bile we need, and therefore make more cholesterol. It is not the cholesterol in the diet that is responsible for high levels in the blood but rather the amount of fat in the diet.
In fact the human intestine has a limited capacity to absorb dietary cholesterol. It is the dietary fat content not the cholesterol that is the switch, but tales keep coming. Last week's FLASH report indicated that a government commission is revising its stance to indicate that the cholesterol in the diet doesn't matter much. I said this four decades ago.
Far more important in my judgment in all of this talk to which I have contributed much, much more important than the cholesterol level is the size of the artery. The dimension of the artery is determined by its flow. Exercise makes larger arteries. (3)
Who cares what your cholesterol is if your artery is an inch across?
Take a jog instead of a Lipitor.
References:
1) Keys, A. Kimura N. et al Lessons from Serum Cholesterol Studies from Japan, Hawaii, and Los Angeles Ann. Int. Med.1958; 48:83-94.
2) Bortz, W. The Pathogenesis of Hypercholesterolemia. 1974, Annals Internal Med. 80: 738-746.
3) Haskell W.L et al Coronary Artery Size and Dilating Capacity in Ultradistance