Thursday, November 4, 2010
MORE BAD SCIENCE? THAT'S EGGSACTLY WHAT IT IS - TOM NAUGHTON
According to a brand-new study, we common folks have a real problem with our diets: namely, we don’t appear to be letting bad scientists scare us away from real foods quite as much as we once did:
The public’s attention is beginning to drift away from the anti-cholesterol message that doctors have been preaching for 40 years, according to the authors of a review in the November 2010 issue of the Canadian Journal of Cardiology.
“A widespread misconception has been developing among the Canadian public and among physicians. It is increasingly believed that consumption of dietary cholesterol and egg yolks is harmless,” Dr J. David Spence and colleagues state.
Hmmm … perhaps the public believes egg yolks are harmless because egg yolks are harmless. After years of making omelets with Egg Beaters and other frankenfoods, it could be that people are thinking to themselves, “You know, my grandma ate eggs every day, and she was 97 before the yolks finally killed her.”
The long-standing recommendation to limit dietary cholesterol is still important, especially for people at risk for cardiovascular disease, but a single egg yolk contains approximately 215 mg to 275 mg of cholesterol, more than the 200-mg daily limit recommended by the American Heart Association and National Cholesterol Education Program, and even more than some infamous fast-food items such as KFC’s Double Down or Hardee’s Monster Thickburger, the authors note.
Allow me to interpret that gobbledygook: Eggs are bad because a single yolk contains more cholesterol than the daily limit recommended by organizations that don’t know diddly about heart disease and believe Cocoa Puffs are good for your heart.
Also, eggs are bad because they contain more cholesterol than foods that don’t actually contain much cholesterol, such as chicken and hamburgers. This is akin to saying strawberries are bad because just 10 of them contain more fructose than 50 pounds of sausage.
“We have become increasingly concerned about the pervasive success of egg marketing propaganda,” including a brochure touting the benefits of eggs promoted by the Heart and Stroke Foundation of Canada, “quoting directly from the egg marketing propaganda,” Spence told HeartWire. “After I received that, I called the HSF and offered to meet with them to discuss the evidence, but I was brushed off as if I were someone they had never heard of.”
Oh, now, I don’t think they brushed you off as if you were someone they’ve never heard of. I’m guessing you were brushed off precisely because they have heard of you. I’ll bet the conversation in their offices went something like this:
“It’s Dr. Spence on the phone. Again.”
“You know, the nut-job who still thinks eggs are killers in spite of all the evidence to the contrary.”
“Oh, him. Uh … tell him we’re busy.”
“Despite widespread belief to the contrary, it is simply not true that dietary cholesterol is harmless,” because research over the past 40 years supports reducing dietary cholesterol to reduce LDL levels, which in turn reduces coronary risk, according to the authors.
Ah, yes … teleoanalysis in action. In case you didn’t watch the video of my Big Fat Fiasco speech, here’s how teleoanalysis works:
We cannot prove, in spite of many clinical-study attempts, that A (low-cholesterol diet) causes C (reduction in heart disease). But … if we can prove that A (low-cholesterol diet) sometimes leads to B (lower cholesterol in the blood) and B (lower cholesterol via statins) sometimes leads to C (reduction in heart disease), we can still claim that A causes C.
So that proves egg yolks will kill you … see?
The only trouble with Dr. Spence’s logic (besides the fact that teleoanlysis is utter hogwash) is that several studies have shown no connection between the amount of cholesterol you consume and the level of cholesterol in your blood — even Ancel Keys eventually admitted that fact. And of course, the link between high cholesterol and heart disease is about as statistically weak as you can get.
Epidemiological studies of egg consumption that failed to show a link between eggs and cardiovascular disease in healthy people were not powered to show an effect in healthy people …
Allow me to interpret again: dangit, if only we’d had a chance to crunch the numbers ourselves, we could have “powered” the data into producing the result we wanted.
… but did show an increased risk of cardiovascular disease with egg consumption among diabetics.
Or as a separate article in Science Daily about the same study explained:
The authors point out that in both studies, those who developed diabetes while consuming an egg a day doubled their risk of cardiovascular disease compared to those eating less than an egg a week.
We’ve covered those observational studies before. Eggs were associated with heart disease among people who also developed type 2 diabetes, but not among those who didn’t. In other words, the link only shows up in people with lousy diets overall.
Those would be people Dr. Mike Eades calls “non-adherers” and I call “people who don’t give a @#$%.” They don’t care if eggs are (supposedly) bad for them. They also don’t care if sugar is bad for them, or if smoking is bad for them. One of the studies noted specifically that the subjects who consumed more than one egg per day were also older, fatter, and more likely to smoke.
The studies also showed a significant increase of new onset diabetes with regular egg consumption.
Wowzers … such bad-science thinking, they didn’t even bother with the phrase “was associated with” this time. Read that sentence without knowing any better, and you’d think eating eggs causes diabetes. So let’s see how that idea holds up against actual evidence.
In the chart below, I plotted the rate of diabetes over the past several decades (in red), along with the per-capita consumption of eggs during the same period (in blue).
Hmmm … looks like back in the 1950s, when egg consumption was far higher than it is today, we had an amazingly low rate of diabetes. It would also appear that diabetes rates went up while per-capita egg consumption was going down. So what can we conclude from this? Thinking … thinking … aha, I’ve got it! — eggs don’t actually cause diabetes, or we’d see consistent and repeatable evidence that they do. No consistency, no scientific validity.
The authors conclude, “There is no question that egg white is classed as a valuable source of high-quality protein. Egg yolks, however, are not something that should be eaten indiscriminately by adults without regard to their global cardiovascular risk, genetic predisposition to heart attacks and overall food habits.”
The blogger concludes: the authors are lousy scientists
To read Tom's full article and leave a comment, right click here.