The problem that I have with weight loss dietary supplements is that they are not effective in the long-term and even worse is that many don't work whatsoever. However they can help and because they can provide help with weight loss, many people tend to buy and to use them.
I am not against the use of weight loss supplements as long as the supplement does not cause harm to your health and as long as it works.

Now, remember, it is called a dietary weight loss supplement because it only supplements your diet, it can't be of much help if you don't make an effort of eating healthier food and being more active. Some are good enough to reduce the appetite which is great and also boost your metabolism but even then if you don't make an effort to eat better foods and be active, don't expect good, especially fast results. Weight loss has been, is and will always be based on dieting and regular physical activity. In order to make changes to your body, no matter if the change that you desire is muscle gain, weight loss or anything else, you will need to do one of the two things that I mentioned, both is the best but some people because of certain circumstances only do one and it is possible to make some progress in both muscle gain and weight loss with just one but it is much less efficient by which I mean that it can be much slower to progress.

Let's say that you use a supplement that can enhance your metabolism, no supplement can do a better job than intense physical effort, such as jumping rope fast or sprinting, it just can't if you ever wondered if it can, so you will not be as efficient if you only count on that. Your body can burn more fat but only if you make it, through being more active because if you increase the level of activity the body will have to burn more fat to provide you with fuel, the more active you are, the more fuel will be required, it's literally just like a car, the more you drive it, the more money you will need to pay for gas because it will require/consume more.

Now, going back to supplements, I don't really use them but I have heard good things in general about Forskolin and from what I read about the science behind it, it looks like a good supplement. It can provide a better metabolism but also helps your health, for some it can be a good choice.
Check out its website for more info. It is 100% natural.