Razib Khan One-stop-shopping for all of my content

April 23, 2017

The case against nutrition “science”

Filed under: cholesterol,Nutrition — Razib Khan @ 12:11 pm

My attitude toward nutrition science is to be skeptical of everything. I am of the generation that lived through the SnackWells fat-free cookie craze (demand was so high at one point that there was a problem with continuous understocking). A friend who is a professor of biology once admitted to me that part of him feels somewhat bad for anti-vaccination believers, because when it comes to nutrition he and many of his colleagues take a very jaundiced view of any orthodoxy. The surfeit of observational studies combined with the huge revenues at stake mean that skepticism is warranted.

This puts the public, and those who serve them in a peculiar position. Last year I recall going to a restaurant where some of the menu items were labeled as “low cholesterol, heart healthy.” I told our server that there is no evidence that dietary cholesterol has any effect on serum levels in your body. But the overhang of nutritional orthodoxy persists, and the American Heart Associations prominence and tendency to be a lagging indictor of the science is going to cast a pall over “public awareness” for decades.

Now researchers are going back to the original studies which supported modern orthodoxy, and finding results that are surprising. Re-evaluation of the traditional diet-heart hypothesis: analysis of recovered data from Minnesota Coronary Experiment (1968-73). Here is the conclusion:

Available evidence from randomized controlled trials shows that replacement of saturated fat in the diet with linoleic acid effectively lowers serum cholesterol but does not support the hypothesis that this translates to a lower risk of death from coronary heart disease or all causes. Findings from the Minnesota Coronary Experiment add to growing evidence that incomplete publication has contributed to overestimation of the benefits of replacing saturated fat with vegetable oils rich in linoleic acid.

The whole story is told over at Scientific American.

April 8, 2010

Evolutionary fitness & nutrition

Filed under: Diet,Genetics,Human Evolution,Nutrition — Razib @ 7:37 pm

Russ Roberts recently had a discussion on Econtalk with Arthur de Vany. A lot of it covered baseball and social science, but he also spent a lot of time on “evolutionary fitness” (see the website at the link). I agree with a lot of what he had to say, but felt that some of his assertions about past evolutionary history exhibited too much certitude in the consensus of the field. In particular, when it comes to nutrition I think that evolutionary informed diets may need to take into account individual differences more than they do. I think there’s an unfortunate tendency of many people who find a particular diet which works for them to strongly extrapolate the efficacy of that diet to everyone else to the same extent. Probably limiting strong advice to near relatives would get rid of most of my concerns since families would share many of the same predispositions.


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