It's the same reasoning as why insurance gives better deals to people of greater age.. They are seen to have more experience and be more "mature " to drive safer if you have more years driving your insurance goes down.. same concept
Answer:
I do not think it is possible. You can loose weight by not consuming anything (not receiving proper nutrition) and it can be damaging to the body. Also without the proper nutrients is would be hard to maintain fitness because you would lack energy. If you don't have nutrition your hair,nails,bones and skin with become weak and you will feel drained and tired all the time. Yes you could lose weight but your body wouldn't be healthy.
Explanation:
That can be taken many different ways maybe: they push themselves to hard and don’t know when to take a break or they cant settle down, sleep or, don’t know when to stop.