国际肥胖论坛（ National Obesity Forum ）的发言人Tam Fry说：“我很惊讶Wii Fit系统说儿童是胖子。BMI系统还不够完美，儿童就不能符合这个标准。”他说，“儿童的BMI可以每个月改变，并且很健康强壮。”
Tam Fry拜访并反应给任天堂Wii Fit中的这个问题。“我很担心假如孩子用这个游戏，我相信你们将得到父母的警告。”任天堂认识到了问题严重性，下面是任天堂官方解释全文。
"The BMI classifications featured within Wii Fit are universal, standard measurements widely used within the medical and fitness profession. We have used BMI and its associated terminology as the in-game measurement in Wii Fit as it is a widely recognised indicator of a healthy weight range since it measures a player's weight, scaled to their height.
"As such it is the best available generic measurement that can assess a layer's progress whilst using Wii Fit. The different classifications applied in Wii Fit are those used officially with BMI.
"As stated in the Wii Fit manual, BMI is essentially a measure of body fat, based on an adult height and weight. Wii Fit is still capable of measuring the BMI for people aged between 2 and 20 BUT the resulting figures may not be entirely accurate for younger age groups due to varying levels of development.
"The BMI results will differ depending on an individual's stage of development. People with more muscle mass than normal will also have a higher BMI rating due to the heavy weight of muscle tissue, so the resulting figures should be used for reference purposes only.
"We appreciate that some players might want to keep their in-game assessment details private. Users playing Wii Fit have the option to hide their on screen weight so it will not be seen when playing in a group environment. In addition, if users prefer to play Wii Fit in a group environment, but do not wish their BMI rating to be viewed, they an choose to play the Wii Fit activities as a GUEST without having to participate in the weighing and BMI measuring process."