It's probably safe (depending upon where you got it from) but don't expect it to work. It's snake oil.
Best weight loss pill I ever had was Panadol Osteo. I started using those at the beginning of 2012 and in just under 6 months had lost 23 kgs / 50 lbs.
Of course, the pills didn't do it without some help from me. They relieved the arthritis in my feet so that I was able to get out and walk 6 to 10 km every day. And THAT got the weight down. :)
No, but I heard fork putdowns are the best exercises you can do for weightloss. Takes little to no effort.