For starters, cholesterol from animal foods does not have some magical ability to set up permanent camp in your bloodstream and turn into plaque, just by sheer virtue of its animal-foodness. This was a common line of thought decades ago, but as research progressed, we figured out that the body is actually pretty awesome at regulating cholesterol production in response to what we ingest from food. As this paper from 2009 explains, the supposed link between dietary and serum cholesterol stems from studies that had fundamental design flaws, failed to separate the effects of cholesterol different types of fat intake, or were performed on animals that are obligate herbivores (hey there, rabbits!). The doctors in “Forks Over Knives,” it seems, are among the few stragglers who still believe dietary cholesterol is harmful.
Most people (about 70% of the population) are “hypo-responders” when it comes to cholesterol intake—meaning the cholesterol they eat from food has a negligible effect on the total cholesterol in their blood. A smaller slice of the population (“hyper-responders”) see a greater rise in blood cholesterol after eating high-cholesterol foods, but the change is because both LDL and HDL increase proportionally, preserving the cholesterol ratio and leaving heart disease risk the same as what it was before. (As more evidence, a similar study (PDF) found no change in LDL/HDL ratio in either they hypo-responders or hyper-responders, even when feeding folks an extra 640 mg of cholesterol per day.)
Not only that, but some cholesterol-rich foods like eggs have actually been shown to make LDL (the so-called “bad” cholesterol) less atherogenic by increasing its particle size. And in one study of diabetics, a high-protein, high-cholesterol diet improved HDL more than a similar high-protein diet with a low cholesterol content (though it was likely other components of the foods involved, rather than the dietary cholesterol itself, that caused this). It’s a weird, wobbly stretch to paint animal foods as a death knell because they contain cholesterol.
No comments:
Post a Comment