Yes you will lose weight and build lean muscle. You need to exercise and get your diet in check too though. Don't just consume protein via shakes. If you want to lose weight, google Bodybuilder Diet. You'll see they eat only lean protein, veggies, good starches and no junk. Simple as that.
Snazzy, I would not use this as a meal *replacement*. It is a great *supplement* to a clean diet. I use this protein for in between meals and after workouts. ALP is right that a diet of lean protein, lots of veggies and good starches will get you where you need to be. If you use this protein as a meal in and of itself, you will not succeed. I have the shakes as snacks WITH some celery or carrots so my stomach gets something solid with it. Definitely look up a bodybuilder diet and if you stick to it along with exercise, you will be on your way to a healthier weight :)
No don't use supplements to lose weight. Eating actual food creates a thermal effect which burns calories as opposed to sucking down liquid calories. Jeeze why are people so clueless and desperate. Eat clean balanced meals and weight lift + intense cardio. Its the only way bro and I dare you to try the quick diet gimmicks cause 5 years from now you will still be out of shape and asking the same question about other products. Read the book Burn the fat feed the muscle.