A Mathematical Challenge to Obesity - 3 years for weight to stablise

  • Found this article from the New York Times yesterday on using maths to model changes to the human body due to food intake. Since I can't insert a link, you'll need to copy and paste nytimes.com/2012/05/15/science/a-mathematical-challenge-to-obesity.html

    The most interesting part was:

    Quote:
    What new information did your equation render?

    That the conventional wisdom of 3,500 calories less is what it takes to lose a pound of weight is wrong. The body changes as you lose. Interestingly, we also found that the fatter you get, the easier it is to gain weight. An extra 10 calories a day puts more weight onto an obese person than on a thinner one.

    Also, there’s a time constant that’s an important factor in weight loss. That’s because if you reduce your caloric intake, after a while, your body reaches equilibrium. It actually takes about three years for a dieter to reach their new “steady state.” Our model predicts that if you eat 100 calories fewer a day, in three years you will, on average, lose 10 pounds — if you don’t cheat.

    Another finding: Huge variations in your daily food intake will not cause variations in weight, as long as your average food intake over a year is about the same. This is because a person’s body will respond slowly to the food intake.
    I wonder if that means that it takes 3 years for your body to take a new weight as a set point.
  • Quote: I wonder if that means that it takes 3 years for your body to take a new weight as a set point.
    Sounds like it... phew! Thanks for the post, very interesting article! I was especially struck by this:

    Quote:
    One of the things the numbers have shown us is that weight change, up or down, takes a very, very long time. All diets work. But the reaction time is really slow: on the order of a year.

    People don’t wait long enough to see what they are going to stabilize at. So if you drop weight and return to your old eating habits, the time it takes to crawl back to your old weight is something like three years. To help people understand this better, we’ve posted an interactive version of our model at bwsimulator.niddk.nih.gov. People can plug in their information and learn how much they’ll need to reduce their intake and increase their activity to lose. It will also give them a rough sense of how much time it will take to reach the goal. Applied mathematics in action!
  • I find that is true about weight stabilization over the long haul. I used to weigh 100 pounds more than I do now. That was almost two decades ago and the journey has included many periods of weight stabilization at different levels. The weight always wants to come back but I won't let it. That is what maintenance is.

    Just from the exerpts posted here, though, I think it is wrong to say blanketedly (is that a word? ) that the basic equation of 3,500 calories less equals a pound. I find that to be right on, personally. The thing is that people burn calories at way different rates and the type of macronutrients eaten affects calorie burn rates in digestion. So time in losing and gaining is indeed a factor and it does take a long time to stabilize.

    Hoping I stabilize someday lol.
  • That' really interesting. I've read elsewhere that most people regain their weight in about three years. I wonder if there's a connection . . . .hmmm.

    Thanks for posting this. It's kind of discouraging for me, though. I've just been maintaining for a few months, and according to what I've read, I have more than two years left to really feel "safe" that I statistically, may not regain my weight.
  • 3 years, huh?
    Well, I guess that's about how long it took to put on...

    Matter is neither created nor destroyed....