Thursday 24 March 2016

Cholesterol

About 10 years ago one Saturday [+/- 2yr - can't remember, who cares] I found myself in the doctor's surgery waiting for my first MOT [general medical check-up] since leaving school.  Being a man, I hadn't made the appointment myself.  Being biddable I hadn't refused to go when The Beloved fixed a time outside of the working week. It being then considered best-practice, my GP donned a rubber glove and palpated my prostate; as well as dipping a Multitest strip in a urine sample [10 for the price of one: Leukocytes; Nitrite; Urobilinogen; Protein; pH; Blood; Specific Gravity; Ketone; Bilirubin; Glucose all at a glance.]; taking my blood pressure and a couple of vials of the fresh stuff for subsequent analysis and passing his hands lightly over my body looking for lumps.  When the cholesterol measure came back he looked at me very stern and said I was to eat fewer rashers and eggs.
"What rashers and eggs? This morning's fry was the first since Easter"
"Well steaks then, give those up"
"It was a long way from steak I was r'ared"
"Cheese then, stop the cheese"
"Okay, I do eat cheese, so I'll cut that down if you advise it although it will make me miserable and frightening to the children"
"And the full fat milk!"
"When I drink milk, I drink milk, I'm not going to pay money for chalk-water"
We compromised on half-fat milk . . . for about 3 weeks [hmmm, not to biddable, not so compliant],

Years later, I was back in the surgery for another check-up. I'd found a polyp [like Ronald Reagan] up my nose  and thought I may as well get a full MOT if I was going to ante-up €60 for a visit.  This time prostate palpation and a test for prostate-specific antigen PSA was optional because the medical community had reluctantly acknowledged that there was no evidence that either test reliably identified prostate cancer. The false positives were subjected yo needless anxiety and/or surgery, the false negatives metastasised and died aNNyway. He was also much more piano about cholesterol being driven by dietary intake and hectoring me about cheese and eggs. My cholesterol  was still as high as it had been several years earlier, so I was offered a course of statins to help reduce the bad LDL cholesterol.  As that course was going to last the rest of my life and cost money for a statistically small [but significant] benefit, I declined. In fairness, he wasn't pushing them too hard, although he himself was on them, having had a heart 'incident'.

What strikes me most forcibly about this volte-face is not the fact that fashions change in medicine as in haute couture; it's the certainty with which everyone rows in behind the current best practice. The road to truth is littered with ideas that subsequently prove to be wrong. So it's better to push your agenda and sincerely-held beliefs with a note of humility or even skepticism.  Statins are known to reduce the concentration of low-density-lipoprotein cholesterol rather more effectively than the plant stanol esters in, say, Benecol. They are biggest $$$-earner for Megapharm Inc. A desire for cartoon simplicity has taken on the idea that if LDL-cholesterol is bad, then high-density-lipoprotein HDL cholesterol must be good. Indeed a whole industry has built up to find out exactly how HDL will prevent you from a) getting atherosclerosis, b) coronary artery occlusion; c) heart attack d) early death.

Dozens of scientific papers have investigated the niceties of the mechanisms of plaque removal, widening of the arteries and other details of HDL's beneficial effects. The latest study shows that, regardless of all this work, HDL-C is more strongly associated with heart attacks and death than the opposite!  We should treat this finding with due skepticism because the lads with the high-level of circulating HDL-C had it  because they all had a rare mutation in the gene SCARB1 for the HDL-receptor. Hazy [or more likely certain] as we are about mechanistic connexions among HDL, fatty-plaques, atherosclerosis it seems possible that having a nobbled receptor is what causes the heart attacks rather than the HDL concentration per se. Watch this space; more studies, some contradictory, are coming down the track.  Heart disease is big business and Mega-pharma needs basic science to find leads for new drugs that it can sell at fantastic prices to medical insurance companies. And the food engineers are coat-tailing on this magic carpet to El Dorado. Some marketing dork had the contemptible idea of pushing rolled porridge oats as 'the fat-free breakfast' a few years ago.

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