"Last Gasp of A Failing Theory"
From Nina Planck:
If I remember my college philosophy of science course, Thomas Kuhn explained, in The Structure of Scientific Revolutions (1962) how science lurches forward from one reigning hypothesis (the sun revolves around the earth) to another (the earth revolves around the sun). And what a mess it is, at the crucial moments, as one hypothesis collapses under the weight of new evidence, but before proponents of the new hypothesis have all the facts they need to prove it - or at least to give it the credibility required to make it Top Dog among hypotheses.
The lurches are the part I remember. The tidy times before and after - when 'everyone' believes in a geocentric universe or flat earth, and later, when 'everyone' knows how the solar system works, or that the globe is round - are less interesting, I think, than the calmer periods in between. These turbulent periods, Kuhn told us, were a crucial part of scientific discovery and revolution - the overturning of old ideas, or at least their tweaking. Kuhn called the result of the lurches a 'paradigm shift.'
We are amidst such a lurch, I believe, in the study of diet and heart disease. The reigning theory, at least 100 years old, is called the lipid hypothesis. It refers to the idea that dietary fats, and saturated fats in particular, 'clog' arteries with cholesterol (among other things) and cause heart disease and - this is key - premature mortality. Saturated fats - both natural (butter) and man-made (trans fats) - are, therefore, considered dietary villains.
The lipid hypothesis has been around since at least 1900, and it was 'proven,' initially, by feeding cholesterol-rich foods to rabbits, who are herbivores without the ability to metabolize cholesterol at all. Their arteries became clogged.
Many skeptics have doubted the theory since. Slowly, they are gaining momentum, because they are assembling from excellent data facts that, as Kuhn pointed out, don't fit the lipid theory. He called such facts 'anomalies.' (Reagan did say facts were 'stubborn things.') Anomalies in the cholesterol theory of heart disease are indeed mounting.
In today's New York Times, Jane Brody demonstrates the desperate logic of those who are perplexed that the reigning theory - butter is bad for you - doesn't seem to fit the facts. Brody is not alone. The theory is increasingly contradicted by clinical data.
This is what happened to Brody, by her own account. Her HDL, VLDL, triglycerides, blood pressure, and weight were all excellent. But her 'total cholesterol' had crept up to 222 - this is regarded as 'high' and 'dangerous' - and her LDL was also 'high' at 134.
So she decided to lose weight (though it wasn't clear why) and take a plant stanol to lower LDL. Later she was retested. Both total cholesterol and LDL were higher.
She decided to take further steps. She 'further' limited red meat and always ate it without the fat; she decided to 'stick to' low-fat ice cream; she ate more fish and took fish oil; and she ate more fiber. At the next test, her total cholesterol and LDL were both higher.
This suggests that reducing fats, natural saturated fats (we can assume from her writings that Brody doesn't eat artificial trans fats), and red meat do not have the predicted effect on total cholesterol and LDL. This is what Kuhn called anomalies: observations (aka facts) that don't fit the theory.
But Brody is pretty committed to the skim-milk, low-fat, low-saturated fat, light-on-red-meat diet. And she is a determined person, it appears, as well as a determined journalist. Though her doctor wasn't worried, Brody decided that diet was not enough: she would also take statins to lower LDL. Stay tuned.
Statin drugs are the best-selling drugs in the country and include Lipitor. They block the liver from producing cholesterol, one of its natural products. They are known to lower blood levels of LDL. What they are not known to do is save the lives of women who have 'high' cholesterol.
If my mother, who is also in her mid-60s, had Jane Brody's numbers, this is what I would tell her.
Scratch that hypothetical. By now, I hope, you expect candor of me. My mother's numbers are, in fact, similar. And this is what I did tell her.
We know that dietary cholesterol has very little effect on blood cholesterol. That is why cholesterol-rich foods like egg yolks are back on the menu. People who eat more eggs have less heart disease. (JAMA, Hu et al, 1999)
We know that the figure 'total cholesterol' is a poor predictor of heart disease mortality (Framingham study), especially in women. According to James Wright of the University of British Columbia, cholesterol is the weakest risk factor in women for heart disease.
We know that traditional diets contain abundant meat and saturated fats and do not suffer from heart disease. Mann, for example, studied the Masai (meat-eaters and milk and blood drinkers in Kenya) and found they had healthy lipids. In a 20-year study, researchers in Wales found that men who drank more milk had less heart disease, even though cholesterol and blood pressure were similar in the high and low milk drinkers. (Elwood et al, 2005)
We know that the net effect of natural saturated fats, such as milk fat, is to raise HDL. The National Cholesterol Education Program is clear about the virtues of HDL: 'the higher, the better.'
We know that in people over 65, LDL - yes, the 'bad' one - means a longer life. (Journal of American Geriatrics, Schupf et al, 1995). 'There is nothing bad about LDL,' says Joel Kauffman, a cholesterol expert I interviewed. 'There never was.'
We know that statin drugs deplete the body of CoQ10, a nutrient essential for heart health. As cardiologist Peter Langsjoen told me, 'The first thing I do is take my heart patients off statins.' We know that statins have not been proved effective in young people, women, or people over 65. (Ravnskov)
The Center for Medical Consumers puts it this way: 'One might reasonably expect the US government’s cholesterol-treatment guidelines to be firmly based on scientific evidence. [Yet] analysis of the other trials that included healthy but high-risk people without heart disease showed that statins should not be prescribed to women of any age who do not have heart disease or diabetes, or to men older than 69 years who do not have heart disease or diabetes because no benefit was shown for them.' (My emphasis.)
We also know that eating fish, fruit and vegetables, B vitamins (in whole grains), and fiber are all good for your heart. So is moderate consumption of alcohol and dark chocolate, and (probably immoderate) consumption of olive oil. Three cheers. On these things (except perhaps, my immoderate use of olive oil), Jane Brody and I can agree. All these foods, as well as the butter she shuns, are found in traditional diets all over the world.
One more thing. We know that half the people who have heart problems have 'normal' or 'desirable' LDL. (Framingham) Something else must be responsible for these cases of heart disease. What is it? Several hypotheses are in play. One is lack of B vitamins (Dr Kilmer McCully). Another is inflammation. Another is lack of omega-3 fats (wild salmon) and excess of omega-6 fats (corn and soy bean oil).
What's that sound? In the middle distance, I hear the clinking, clunking, rusting, wheezing, creaking sounds of a paradigm shift. It's not pretty - and there will be plenty of bleating by the flat-earthers, as they watch their precious theory crumble - but mark my words: it's coming.
- Nina, August 21, 2007
|
Which is a good thing, I hope every brave soul that has worked with, and experienced the benefits of, low carbing come out of the woodwork.
Linear Mode
