This kind of question comes up from time to time... as someone who has a significantly slower metabolism than they used to, I REALLY don't recommend it.
Lower metabolism means your body is making less energy. That can, IME, contribute to chronic fatigue. Profoundly unfun.
Keep your energy and just overeat. If you're having trouble overeating, then yes, dairy fat is a great way to add a bunch of extra calories. IME, half and half is easier to digest than HC, but YMMV.
1 year