This is a government that is literally out for its pound of flesh.
But, the annual reporting of your BMI will be one more data point in your nationalized health history. I fear that it will become a major determinate as to what types of treatment and the duration of that treatment available to you as you age.
Look at the various causes of all evils that we have seen in the last 100 years - alcohol, second hand smoke, obesity, algar, red dye # 4, man caused global heating, etc. All have some basis in medical/scientific literature. But, like almost all POLITICALLY motivated movements, when you make a detailed examination you discover that they, like water and oxygen, are lethal only in laboratory studies where the exposure is many hundreds of times of what the average person would be exposed to during their lifetime.
Yes, we are fat. But, I much prefer President Kennedy's approach (a national awards program for exercise, 50-mile endurance walks, and pictures of the first family playing touch football) than providing a bean counter with “justification” to deny medical support>