Cutting weight cuts the number of cells.

Actually, losing bodyfat reduces what is inside those fat cells (fat, glycerol, and water), but does not get rid of the fat cells themselves. Doesn't really matter, because you will still get lean. But that is how it works.

A compound called Grelin is what is responsible

Ghrelin is a hormone that kicks in when your body thinks it is TIME to eat, not that you SHOULD eat. If you are used to eating multiple times throughout the day, ghrelin will kick in around those times, and you will feel hungry. But that hunger will pass in an hour or so. After several days of fasting, you don't get hungry anymore. Obiously, it cannot be purely a hunger signal if it goes away completely.

But the body obviously doesnt want you to be HAPPY that your STARVING.

Probably true, generally, but a fat bastard DOES need to "starve" for a period of time, to correct the overindulgence they have been abusing their body with for years and years to get into that situation in the first place.

The longest fast on record was something like 382 days. He was Scotsman in the 1970's/1980's, and he started fasting at 426 pounds. He kept going for more than a year, and ended his fast at around 180 pounds.

He had no health complications whatsoever, and kept the fat off for the rest of his life.