Obesity and Genetics

[jeff_duntemann]

Yesterday I ran across a nice article in the New York Times, which is an excerpt from Gina Kolata's new book, Rethinking Thin. I'd heard the odd reference to fifty-year-old research from Jules Hirsch, a physician at Rockefeller University, that strongly correlated (70 percent-strong!)

Comments

genes...

[anonymous]

In my own case, I know that my mother's side of the family leans toward trim, while my father's side has been more on the heavy side. For my part, I can get trim and stay so only through some fairly serious exercise. By that I mean 4-5 days a week, and 1 hour+ per day, half of which is cardio.

Diet ought to make a big difference, as I am hypoglycemic, but unless I take fairly drastic steps, it does not. I can subsist on salads, and not lose weight. In more ordinary eating, I curse the diet fad folks who continue to purge fat from our food -- fat tells the pancreas to stop producing insulin, so it is a tool for me.

I'm currently overdue to dive into serious exercise, and my weight now is similar to my father's weight 40 years ago. The good news is that I know from experience that it will do the trick. The bad news is that in this climate, I will battle heat, humidity and pollen, as well as fat.

Bill Meyer

Obesity and genetics

[happy_hacker]

A blessing upon your head

Scientific process and weight

[chris_gerrib]

There are two problems with the scientific process, and neither of them are new.

First, unless you have a theory to prove or disprove, the process doesn't work. The story of Dr. Jenner, who demonstrated that cow pox was a vaccine against smallpox, is as good as any. He couldn't explain why it worked, so it was not generally accepted.

Second, scientists are people too. The example here is "luminiferous ether." Up until the early 1900s, scientists thought that light, which is a wave, had to be transmitted in something. That something had to be a magical substance, with no weight or mass. Then this Swiss patent clerk (you may have heard of him - guy named Einstein) came in and said "well, duh, light is a wave AND a particle." This was not terribly popular, and wasn't accepted by mainstream science until the 1920s - when the old fogies had retired

[jetfx]

While your conclusion that metabolism is one of the major factors in body weight is true, it ignores the fact that obesity rates have increases dramatically since the Second World War. I doubt that this is because people with slow metabolisms breed at a much higher rate, but rather that there has been a change in diet and lifestyle in general. It's the old nature vs nurture debate again.

I would say that both genetics and lifestyle are heavily intertwined in a way that it is very hard to discern which is the dominant factor in obesity. It's likely that we never be able to tell and leave them as just nature/nurture, just like space/time.

[jeff_duntemann]

The two issues that I see as appearing since WWII are reduction in sleep time, and the explosion of the use of sugar, particularly in the form of high-fructose corn syrup. Children seem peculiarly vulnerable to HFCS, but the science is still pretty sparse.

Also, the cost of food in real dollars has come down a lot in the last forty years or so. People with the fat gene who might have stayed at least a little thinner may have picked up additional weight simply because eating more is cheap.

I agree that it's complex, and in fact that's the main thrust of this (long) post: That obesity is a complex business, and until we recognize the presence of that complexity, we will get nowhere in trying to address obesity as a public health issue.

[alanajoli]

Like all of the equations, exercise as a factor probably depends on the person. I tore a ligament in my knee, making me pretty much laid up on a couch in all my spare time after I'd been exercising regularly (medium impact, 1/2 hour to an hour per day) for six weeks. I put on about ten to twelve pounds. Because my knee's still not better, I'm doing the Weight Watchers plan with my husband. (Really, eliminating my peanut butter and chocolate intake would probably be enough, but it's easier to say no to myself about that factor when I'm actually on a food plan.) That's taking the weight gain back off--but I don't feel as healthy as I did when I was exercising regularly. I miss the work out.