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Showing posts from October, 2012

The man who ate 25 eggs per day: What does this case really tell us?

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Many readers of this blog have probably heard about the case of the man who ate approximately 25 eggs (20 to 30) per day for over 15 years (probably well over), was almost 90 years old (88) when the case was published in the prestigious The New England Journal of Medicine , and was in surprisingly good health ( ). The case was authored by the late Dr. Fred Kern, Jr., a widely published lipid researcher after whom the Kern Lipid Conference is named ( ). One of Kern’s research interests was bile, a bitter-tasting fluid produced by the liver (and stored in the gallbladder) that helps with the digestion of lipids in the small intestine. He frames the man’s case in terms of a compensatory adaptation tied to bile secretion, arguing that this man was rather unique in his ability to deal with a lethal daily dose of dietary cholesterol. Kern seemed to believe that dietary cholesterol was harmful, but that this man was somehow “immune” to it. This is ironic, because often this case is presented

The steep obesity increase in the USA in the 1980s: In a sense, it reflects a major success story

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Obesity rates have increased in the USA over the years, but the steep increase starting around the 1980s is unusual. Wang and Beydoun do a good job at discussing this puzzling phenomenon ( ), and a blog post by Discover Magazine provides a graph (see below) that clear illustrates it ( ). What is the reason for this? You may be tempted to point at increases in calorie intake and/or changes in macronutrient composition, but neither can explain this sharp increase in obesity in the 1980s. The differences in calorie intake and macronutrient composition are simply not large enough to fully account for such a steep increase. And the data is actually full of oddities. For example, an article by Austin and colleagues (which ironically blames calorie consumption for the obesity epidemic) suggests that obese men in a NHANES (2005–2006) sample consumed only 2.2 percent more calories per day on average than normal weight men in a NHANES I (1971–1975) sample ( ). So, what could be the main reason

Of bunnies and bacteria

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I remember when I first learned that a rabbit ate its food twice . This curious dietary practice, called coprophagy, is something I'd witnessed as a child raising my own rabbits and guinea pigs in the backyard. Disgusted by the sight of my pets eating their own feces, I recall trying to keep their cages as clean as possible. Had I known better, I would not have been so quick to remove droppings from their cage because I might've put these animals at risk for nutritional deficiency (1-2). Luckily, I wasn't ever very consistent at keeping their cages clean all the time. Rabbits and guinea pigs, as it turns out, need to eat their own droppings because they provide a valuable source of nutrients like vitamin B12. In the wild, they will normally leave soft droppings at the mouths of their burrows while they go off foraging at dawn or dusk. When they've had their fill of foliage, they return and -- far from being repulsed by having a stack of droppings at the foot of their do

The anatomy of a VAP test report

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The vertical auto profile (VAP) test is an enhanced lipid profile test. It has been proposed, chiefly by the company Atherotech ( ), as a more complete test that relies on direct measurement of previously calculated lipid measures. The VAP test is particularly known for providing direct measurements of LDL cholesterol, instead of calculating them through equations ( ). At the time of this writing, a typical VAP test report would provide direct measures of the cholesterol content of LDL, Lp(a), IDL, HDL, and VLDL particles. It would also provide additional measures referred to as secondary risk factors, notably particle density patterns and apolipoprotein concentrations. Finally, it would provide a customized risk summary and some basic recommendations for treatment. Below is the top part of a typical VAP test report (from Atherotech), showing measures of the cholesterol content of various particles. LDL cholesterol is combined for four particle subtypes, the small-dense subtypes 4 and