In Which the Migraineur Laments the Sorry State of Health Science

First of all, yes, I’ve been away for a while, and no, I don’t know if I’ll be writing regularly again any time soon.

And, my daughter Gillian Rose was born on January 31 – we are all healthy and happy.

Now, on to my topic.  Front page news on today’s New York Times:

http://www.nytimes.com/2009/04/09/health/research/09fat.html?_r=1&ref=todayspaper

The part that really struck me was this (emphasis mine):

Recently, Dr. Kozak put mice predisposed to obesity in a cold room, 41 degrees, for a week. The animals activated their brown fat. As a result, they lost 14 percent of their weight, which constituted 47 percent of their body fat, while eating a high-fat diet with two and a half times more calories than they had consumed at room temperature.

“That’s just by going out in the cold, without any drug treatment,” Dr. Kozak said.

Now, surely it doesn’t take a PhD to realize that changing both the temperature of the room and the diet of the mice introduces a confound into the experiment.  I would expect any freshman science major with a decent grade-point average to recognize that it is impossible to tell from such an experiment, at least as it is described by Kolata (who is, admittedly, not the brightest star among health journalists) whether the mice’s diet led to weight loss, or whether it was the cooler room temperature, or a combination of the two.

And in fact, at least three variables have changed: the temperature of the room, the fat content of the mice’s diet, and one or more of the following: the total calories consumed by the mice; the total amount of carbohydrate; the total amount of protein; or the ratios of fat, carbohydrate, and protein.  As Gary Taubes points out, you can’t alter one macronutrient without altering something else about the diet.

Of course, if you believe that a calorie is a calorie is a calorie, then the fact that the mice lost weight on more calories would suggest that it was the room temperature that caused the weight loss.  But if you recognize that the body treats fat differently than carbohydrates, that the body can waste fat calories much more easily than carb calories, then the entire experiment (again, as described by Kolata) is suspect.

Put another way – I’ve lived in 65-degree rooms every winter my whole adult life.  Why didn’t I maintain a healthy weight until I upped the fat and lowered the carbs?