Also be skeptical of any promise to reduce your size by “inches.” The usual technique is to measure you many times, and add up all the measurements. So if you lose 1/8 inch just above the knee, and 1/8 inch a little above that, and 1/8 inch a little higher, etc. - they add it all up and call it an inch. So if they measure in 10 places, they call that 1 2/8 inches. “But that’s not all…”
Of course, you have two legs, so they then measure the other one. They add that to the first one - wow! You lost 2 1/2 inches!!! Uh, no. It’s only 1/8 inch.
If people didn’t fall for this I would think it was funny. After all, why stop at measuring in 10 places? Why not measure in 100 places on each leg? Then measure in 100 places on the torso. Hey, how did that body wrap work? Great! I lost 50 inches! I completely disappeared!