“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!”
Better yet, what would the weight simulator say?
I fired it up (after installing the correct java plug-in, which I apparently did not have) and briefly read the onscreen directions that looked something like this:
First I entered my height, weight (before diet), and clicked on “Estimate my activity level.” That button allows you to select various activities that generally characterize your daily life. I tried my best to approximate both how much physical activity I did before starting my diet/exercise routine according to their options. Then in the main section in the tab “Set your Goal weight,” I filled in all the green highlighted areas (see below). Clicking on the green box titled “Detailed” allows the option to list how you are increasing your physical activity, including which exercises (running, walking, or cycling), how often, and how long. I made sure to say I wanted to lose the weight within a year, but then specified a five year time window in the simulation (although it’s displayed in # of days), so it will show if my weight comes back. Then I pressed “Run Simulation” and played around with the graphical display.
The kicker: when I kept track of my own weight using my Wii Fit, I could view a graph of my weight over the course of a whole year, which I did. Astonishingly, my Wii graph looked just like this one. Somehow, my real life weight loss scenario and this mathematical calculator using algorithms I will never understand, came to the same conclusion about how the weight would come off me and how long it would take. If I counted calories (which I don’t) I could follow this simulator’s calorie suggestion and never gain back the weight! On a different note, as I went lower and lower with my ideal weight, it actually pops up with a warning, telling me “This simulation results in a dangerously low BMI,” whoops. Nice to know they are telling me what’s healthy and what’s not! I’ll probably keep playing with this thing and even start to re-think my weight loss goals. Everyone should check this out and play around to see how much they should be eating, or are actually eating!! In my case, it seems eating 400 additional calories a day for a year would result in a 20 pound weight gain if I went backwards. BUT: short bursts of eating that are few and far between: indulgences, that is, will not cause long term weight gain. So I don’t have to feel guilty about “cheating” by eating out for a friend’s birthday or whatnot! This is mentioned in the rest of the NY Times article, which I highly recommend. Anyway, I think this simulator is seriously cool…Props to Dr. Kevin Hall of the National Institute of Diabetes and Digestive and Kidney Diseases for making this tool free and available!