Wednesday, March 30, 2011

What the )*(@)#($*@ is Excess Weight?

So the flurry of news stories about the lap band got me thinking again. What is success as defined in these various articles/studies? All of them have some reference to "excess weight". Well, what the hell is excess weight and how is it calculated? Is it "ideal weight"?  BMI at the top of the "normal" zone? Heck if I know, but it bugged me enough to do some digging.

So first step, figure out what the heck excess weight is. I found this:

Calculating Excess Weight Loss
Excess weight is the amount of weight over ideal weight. Ideal weights are published in the Metropolitan Life Insurance height-weight tables. These tables display weight ranges for small, medium, and large frame sizes. Ideal weight is considered to be the maximum weight in the large frame size range. To calculate the percentage of excess weight loss (%EWL) divide weight lost by maximum excess weight and multiply by 100. The tables include one inch of height for shoes, so an inch needs to be added to actual height to see the correct weight range. (source)

According to the Metropolitan Life Insurance height weight table, my weight for height (5'8") and frame (small) is a range of: 126-139 lbs. So, my "ideal weight" is 139 lbs. BUT if you look above, ideal weight is the maximum weight in the large frame size range - 146-167 lbs. Therefore, my "ideal weight" for this calculation is 167 lbs.
Calculating the percentage of excess weight loss is divide the weight lost by the maximum excess weight and multiply by 100. (OMG, keep in mind this reminds me of one of those Tim is running this fast and Suzie is running that fast, but this happens and that happens, so who gets there first, it is highly likely that I have screwed this up!!!)
  • Divide weight lost = 105 lbs (234 lbs max weight - 129 lbs = 105 lbs)
  • Maximum excess weight = 67 lbs (234 lbs max weight - 167 lbs ideal weight)
  • Multiply by 100
  • EWL Answer: 156.7% ---I think, please see "OMG" note above. HA!
OK, great, but let's use a more realistic calculation for me using the high end that matches my frame size.
  • Divide weight lost = 105 lbs (234 lbs max weight - 129 lbs = 105 lbs)
  • Maximum excess weight = 95 lbs (234 lbs max weight - 139 lbs ideal weight)
  • Multiply by 100
  • EWL Answer: 110.5%
I think this one is a more accurate measurement for me.

From the same source, it says: "the range reported by the best published Gastric Banding studies worldwide, which generally show about 60% EWL after 2-3 years."
Anyway, I thought it was interesting and answered the question for me. Try it, you might find based on how the "experts" calculate EWL that you are much further along than you thought!

I'm a little verklempt from all this math, amongst yourselves...or in the comments!


Justawallflower said...

wow, that just gave me a headache! lol! I think I will check it out though! Thanks for sharing

Jacquie said...

Very complicated! How I figure it is the amount of my highest weight less what my goal is. In my case, I had 64 lbs to lose and I have lost 53 lbs so far. In my book, I have almost lost 100% of my excess weight. Definitely not scientific but it works for me!

Gen said...

Its easy - if your ideal weight is 150 and you start at 250, you have 100 to lose. If you lose 60 pounds, you've lost 60% of your excess weight. Make sense? In my case, I think I'm around 60%. But the rest of it is not budging.....

Robin said...

Since banding, I've lost 93% of my excess weight.

Beth Ann said...

You bring up the most interesting things. Thanks for this!! Off to calculate. :)