Personally I think that the BMI is slanted towards being underweight. But I also agree that it isn't a good index for younger children. The simple response here is for Nintendo to make the calculations optional since they are only useful in a dietary regime and NOT needed at all for any of the game play.

The most insulting part is not being called overweight, but that the game then changes the body shape of your Mii! THAT is just cruel :-)

BMI is not a good judge of most people's fitness levels. Muscle mass has alot of variation, and weigh's more then fat. going simply on weight you will get results such as this..
http://www.youtube.com/watch?v=NVK-wXoZPfA&feature=related
which can be hurtful or unsettling to people.
There should be an option to turn it off, especially the avatar changes.

people who play games and see themselves as an attractive avatar, can be more motivated, and a lot more confident in everyday life. forcing avatar changes to avatars can be emotionally hurting to people who bought the game just to have a bit of fun with there family. No person would want to play a game where they look ugly.

I can say, as a user of Wii Fit, that I was offended by the game. I'm naturally more muscular than many women. My body fat % is 24% but my weight is 170 for 5'4"... The game showed my BMI as nearly obese made my Mii grow into this hideous fat body. 24% is quite lean for a 35 year old woman and I guarantee I don't look like the offensive round ball that my Mii looks like.

The game should allow you to put in your body fat% if you know it.

I do not see why folks are all upset about you are being called obese on the wii fit. This is something that I know and I am sure that you know too ,you may not want to know it but there it is. My solution is not to check your weight everyday maybe once an month. Don't get offened when you hear that you are fat just do something about it. I am. I love my wii fit.

If you are confident in your body a game's perception of your body type shouldn't bother you. I was up near the obese part, but have lost 10kg and now sit nicely in the Health Weight range. I wasn't offended (more shocked that I had put on that much) and enjoyed having the target of reducing the size of my Mii, which wasn't that much of a change anyway. If you are more muscly, just put in a higher height, which should lower the BMI. How you feel in and out of your clothes is a better indicator than any number.

I actually enjoy checking my BMI on the WII Fit, I've lost 89lbs since last September. My current BMI is 30.56 as of this morning weighing 178lbs.(which is still considered obese) I still have 45 more pounds I would like to lose. Please don't take it seriously, have fun and don't be so hard on your selves! (smile)

My wife came out as anorexic. I came out as a fatty.
We are both shapely toned athletic people.

But look, Nintendo did not invent the BMI system, so the results are not their doing.

The fact that they use the BMI in this way, however, is a bit questionable. They could at least qualify the screen output to indicate that "BMI is but one indicator for fitness, using a simple division of weight over height" (or whatever the hell it does).

Wii Fit rocks. The BMI thing will only make Nintendo look like they lack judgement skills in developing a product. Nobody wins. They should change it somehow, even if its just to satisfy their market (which, by the way, is their raison d'etre).