The Simplest Solution
And it has nothing to do with tech. The reason why it's always the same people is that those individuals refuse to exercise, and they refuse to stop smoking. Employers can be pretty heavy-handed when it comes to drug testing, so why shouldn't they be just as ruthless in dealing with smokers and fatties? Smoking is slow suicide, and VERY EXPENSIVE suicide at that. And, if someone is 5'2" and weighs 185 lbs, he or she will certainly need to take more sick days. Those sick days are required for a variety of diseases, but always relate back to being FAT.
I don't know how to cure smoking, but I know how to cure obesity. The workplace must include a cardio room and a shower room. At lunchtime, the obese should be required to do 1/2 hour of exercise. If you can fire people for refusing to urinate in a cup, you can also fire them for refusing to control their weight. I'm tired of paying for their sloth.