Body weight simulator

significance

I thought others might be interested in the Body Weight Simulator made available by the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The link is below. It lets you simulate what your weight might be over time, following a particular diet and exercise regime, and what might happen in the maintenance phase (e.g. what sort of bounce you might expect), and can also tell you how many calories you'd need to eat in a day to (a) reach a goal weight in a particular time (this might not always be a realistic target) and (b) maintain that weight once you're there.

http://bwsimulator.niddk.nih.gov/

brndygrl98

*bump*

Thank you so much for sharing!

tjandjmkahrs

Bump!! Thank you!!

juliesummers

bump.
I'll check it out.

amccrazgrl

Bump also.

baptistgirl23

Checking it out later...thanks! )

Apryl546

Bump as well!

Was checking this out when my internet went capooey. Currently on phone!

SevenSix

Thanks for sharing :-)

rubyeskimo

Thank you, this tells me that if I eat 1800 calories a day and just increase my exercise by 5% I'll be at my goal weight within the 180 days it says! Looks like I'll be at my goal by Christmas at this rate!

mbissey

bump

tickletickle

wow so in 90 days i can be goal weight if i do what im doin with an extra 10 mins on my bike a day sounds good to me

Steel6981

Bump, thanks for the info.

iishnova

Thanks for that, I love it!

significance

Glad to hear others are finding it useful, too! I heard about it in a recent episode of "The Health Report", which focused on obesity research and policy. (http://www.abc.net.au/rn/healthreport/stories/2011/3308926.htm in case you are interested in hearing or reading more)

_Ben

Very interesting, a lot of data and other factors that seem to beinvolved, which is very cool

mfpcopine

The mathematician who helped develop this simulator discussed the model and weight loss trends in the United States with The New York Times.

http://www.nytimes.com/2012/05/15/science/a-mathematical-challenge-to-obesity.html?ref=us

A CONVERSATION WITH CARSON CHOW
A Mathematical Challenge to Obesity


"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.

Did you ever solve the question posed to you when you were first hired — what caused the obesity epidemic?

We think so. And it’s something very simple, very obvious, something that few want to hear: The epidemic was caused by the overproduction of food in the United States.

Beginning in the 1970s, there was a change in national agricultural policy. Instead of the government paying farmers not to engage in full production, as was the practice, they were encouraged to grow as much food as they could. At the same time, technological changes and the “green revolution” made our farms much more productive. The price of food plummeted, while the number of calories available to the average American grew by about 1,000 a day.

Well, what do people do when there is extra food around? They eat it! This, of course, is a tremendously controversial idea. However, the model shows that increase in food more than explains the increase in weight.

In the 1950s, when I was growing up, people rarely ate out. Today, Americans dine out — with these large restaurant portions and oil-saturated foods — about five times a week.

Right. Society has changed a lot. With such a huge food supply, food marketing got better and restaurants got cheaper. The low cost of food fueled the growth of the fast-food industry. If food were expensive, you couldn’t have fast food.

People think that the epidemic has to be caused by genetics or that physical activity has gone down. Yet levels of physical activity have not really changed in the past 30 years. As for the genetic argument, yes, there are people who are genetically disposed to obesity, but if they live in societies where there isn’t a lot of food, they don’t get obese. For them, and for us, it’s supply that’s the issue.

Interestingly, we saw that Americans are wasting food at a progressively increasing rate. If Americans were to eat all the food that’s available, we’d be even more obese.

Any practical advice from your number crunching?

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. "