When you consider that a consistent 20 lbs a week would be 80 pounds in a month, you realize that's actually a shitload of weight.
I had a friend who weight 365 lbs. He was able to lose 100 lbs through diet and cycling. It took him six months to do it though, and even that is considered pretty fast to lose a hundred pounds, even for a heavy person. That's 16 pounds a month.
Yes thats true but thats not what i said/meant.. Its fairly normal for an obese person to lose a huge amount within the first week or two of diet and exercise.. and then for it to slow down but still be well above the 2lb a week range. I watched this show ages ago for like a season or two and it was a regular thing..
Losing 20lb week after week is probably not healthy but i didn't see that on the couple of seasons i watched.