Monday, January 24, 2011

Nutritional Stupidity - it is everywhere, especially in the news.

Here we go again - I opened the morning paper and there she was - again. A media darling, she is  British Columbia's go-to dietitian when advice is needed. She is up-beat, charming and so on but .... woefully ignorant or misinformed about nutrition. She is a spokesperson for the "lie" that I mentioned in previous posts. A few days ago I posted my rant about how she upholds the misguided mantra that carbs cause no harm - not even diabetes.

Today Patricia's little sidebar nutritional advice in the Vancouver Sun newspaper counsels us that we should consume healthy fats and reduce intake of bad fats. Because we should consume the fats that "nourishes cells, provides key nutrients and helps our heart instead of the kind that adds unwarranted weight or clogs arteries." Notice how she uses the same word that has been used for more than 40 years to illustrate and paint or draw a picture in your mind about what "bad" things saturated fat do - "it clogs arteries." She then babbles on about oatmeal, whole grain toast, whole grains blah blah blah ....

The newspaper is the worst place to learn about fats and these little sidebar tidbits that passes itself as sound advice is relentless in its recital of 40 years of dietary nonsense. Patricia, here's an inconvenient truth for you: beef fat is 45% unsaturated; chicken skin is 70% unsaturated; butter is 30% unsaturated; lard is 60% unsaturated. They rank right up there with your beloved olive oil.

Here's a bit of history taken from Gary Taubes' research - by the early 1960s there were two competing hypotheses that needed to be tested. The American Heart Association had, by 1961, sided with Ancel Keys' view that fat/cholesterol were at the root of heart disease. The other hypothesis was the view that high levels of triglycerides were at the root of heart disease as well. It was already established  that triglycerides are raised by the consumption of carbohydrates. The research was dominated by those who held to Keys' hypothesis; not surprising considering the difficulties of measuring triglycerides (with a paucity of facilities to do so) as opposed to measuring total cholesterol.

Meanwhile, with advances in technology, research uncovered that there are a number of different types of lipoproteins: VLDL, LDL, HDL, and chylomicrons; from this came the classification of metabolic lipoprotein disorders - low fat diets could remedy high LDL and low carb diets could rectify abnormally high triglycerides. Soon HDL was able to be measured in large populations and it confirmed studies conducted in the 1950s - that when HDL is high, triglycerides are low and vice versa. This meant that triglycerides and HDL are more important factors or markers for heart disease than total cholesterol. It was obvious that a low-carb diet would be beneficial if one did not want to have a cardiac event. Raising HDL would seem to be a better way than to lower LDL or total cholesterol - but there was too much money invested in Keys' hypothesis.

January 17, 1977 was when the studies on HDL, which were so promising in terms of offering salvation against heart disease, came three days after the U.S.A. government announced the publication of the Dietary Goals for the United States in which it promoted a low-fat , high carb diet for all Americans based on Keys' fraudulent research and a lack of further evidence. Like lemmings, the rest of the world followed.

There were critics that railed against Keys' position, rightly so, but George McGovern and his committee  could not wait any longer - he had to show the American people that the government was going to do something/anything. Politics ran over science. Replace fats with carbs was the order of the day. What had been discovered about HDL was ignored but problems arose.

The researchers were faced with a dilemma. Replacing fats with carbs would increase triglycerides. But this would also decrease HDL - the good cholesterol; so, replace fats with polyunsaturated fats was the decision. But these industrial oils were suspected of being carcinogenic. So reducing fat became the advice. By 1980 any discussions of the effect of carbs on HDL were silenced - the advice now was to raise HDL through exercise and losing weight. The way to lose weight was by implementing the low-fat, high carb diets.

Then a way out of the dilemma appeared when it was discovered that there was a way to lower LDL while at the same time raise HDL. And this could happen without adding more carbs or fat to the diet - monounsaturated fats such as olive oil with its oleic acid content was the answer. Monounsaturated fats were neutral. Saturated fats raise both LDL and HDL; carbs lower HDL but also lowers LDL. monounsaturated fats raise HDL and lowers LDL. The Mediterranean diet was "in" but they could not figure out if it was because of a rise in HDL or a decrease in LDL that benefits could be acquired.

But here's the stinker - let Gary Taubes finish it off:

     "The observation that monounsaturated fats both lower LDL cholesterol and raise HDL also came with an ironic twist; the principal fat in red meat, eggs, and bacon is not saturated fat, but the very same monounsaturated fat as in olive oil. The implications are almost impossible to believe after three decades of public-health recommendations suggesting that any red meat consumed should be at least lean, with any excess of fat removed.
     Consider a porterhouse steak with a quarter-inch layer of fat. After broiling, this steak will reduce to almost equal parts fat and protein. Fifty-one percent of the fat is monounsaturated, of which 90 percent is oleic acid. Saturated fat constitutes 45 percent of the total fat, but a third of that is stearic acid, which will increase HDL cholesterol while having no effect on LDL (stearic acid is metabolized in the body to oleic acid, according to Grundy's research). The remaining 4 percent of the fat is polyunsaturated, which lowers LDL cholesterol  but has no meaningful effect on HDL. In sum, perhaps as much as 70 percent of the fat content of a porterhouse steak will improve the relative levels of LDL and HDL cholesterol, compared with what they would be  if carbohydrates such as bread, potatoes, or pasta were consumed. The remaining 30 percent will raise LDL cholesterol but will also raise HDL cholesterol and will have an insignificant effect, if any, on the ratio of total cholesterol to HDL. All of this suggests that eating a porterhouse steak in lieu of bread or potatoes would actually reduce heart-disease risk, although virtually no nutritional authority will say so publicly. The same is true for lard and bacon." (Good Calories, Bad Calories, pp. 168-169).

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