Since years ago when I had great success with Atkins, this has been a "problem" that started around the end of week 2 for me and occured off and on. I KNOW you are going to say, just as a read, no way can I choke down food, but its what I personally have found works to pick my appetite back up.
First off, breakfast. I've always been a skipper. But, this time I wanted to go as strictly by the rules as I could. DANDR says never go more than 6 hours without a meal, even if its just a simple, small protein snack with your supplements. So, every morning I have 2 eggs scrambled with my supplements. Every single morning I woke for like the first 4, I thought O M G, the last thing I want to do is eat right now. But, I cooked them, sat down, took a few bites at least and found once I got a few down, my body got interested in it. So now, I feel hungry in the morning, about 1/2 the time, but I eat no matter what. I've had a very nice consistant weight loss doing this. I make sure I eat 3 times a day no matter what as well. I want my body to come to expect I WILL feed it and therefore not try to reserve anything