PET scan showing distribution of brown fat in a human subject
Here we go again…
Scientists at the Dana-Farber Cancer Institute have discovered that exercise stimulates the production of a hormone that turns white fat into brown, promoting fat loss.
A bit of explanation is in order here. Mammals, including human beings, have two kind of adipose tissue, white fat and brown. Brown fat cells are brown because of the abundance of mitochondria, organelles that oxidize food to release energy. In other parts of the body, the energy released by the mitochondria may serve to power muscle contraction or to move substances in and out of cells, but in brown fat cells the energy is released as heat. Brown fat enables mammals that hibernate to warm up after their long winter nap, and it also helps us to stay warm when it gets cold outside. Think of white fat as the oil tank. Brown fat is the furnace.
Writing in the venerable journal Nature, the study authors reported that exercise in mice and men stimulates muscle cells to produce a protein, irisin, which causes white fat cells to turn into fat-burning brown ones. This in turn leads to fat loss as well as improved glucose tolerance. The authors stated “Irisin could be therapeutic for human metabolic disease and other disorders that are improved with exercise.” An article in the New York Times put it more vividly: “If [researchers] could turn on brown fat in people without putting them in cold rooms or making them exercise night and day, they might have a terrific weight loss treatment.”
Don’t you love that crack about “making them exercise night and day?” That strikes me as a bizarre remark, considering that for a lot of Americans, any exercise at all would be a step in the right direction.
And of course, if this stuff really ever does make it to the market, then the people who took it as a substitute for exercise would be missing out on a thousand and one other documented benefits of physical activity. But that’s not even the main point.
Before we go any farther down this road, I want people to think long and hard about where we are going. Do we really want a society in which self-control, self-discipline, and will power are considered outmoded concepts? To anyone who is wondering what such a society would look like, check out “The Fat Doctor,” that hour-long promotional message for Streamline Surgical, LLP. Each episode tells the story of a couple of patients suffering from malignant obesity. These folks typically are two hundred pounds overweight, three hundred pounds overweight, even four hundred pounds overweight, and they hate their lives, absolutely hate them. They hate everything about their lives, and why wouldn’t they? And they speak with disarming candor about themselves. Not one of them blames his genes, or his mother, or the fast-food companies. “I eat and eat and eat and eat,” is a typical remark. And yet none of them has the will power to turn this insight to his advantage.
This may sound harsh. But as C.S. Lewis said, I am beginning to find out that what people call the cruel doctrines are really the kindest ones in the long run. The reverse is equally true.
Photo via Wikimedia Commons