What is more effective, lipo 6 or hydroxycut?

Neither: Weight loss or fat reduction can only be attained by diet, exercise, or liposuction surgery. Nothing else.

Both help the seller: Neither "helps" the buyer/user more than the other, or many other such products out there. Diet and exercise, along with fewer calories taken in, is the only non-surgical way to lose weight. If you are massively obese, gastric bypass or lap bands are effective and will improve your health/weight. Skip the "snake oil.".