If you read any bodybuilding site or go into health food or vitamin store, you will instantly be bombarded with expensive weight and fat loss supplements. As we all know, those Extra Pounds Cause Many Health Issues. Below I have summarized which of these supplements for weight loss have actually withstood the test of peer-reviewed research.
The weight loss market is a HUGE market and the supplement sector in particular abounds with unsubstantiated claims and overly expensive products. In addition, the FDA has found two dozen weight loss products with carcinogens, controlled substances and other dangerous additives. In my opinion, it’s far safer to go with a name brand supplement for one ingredient that you know has a proven research track record.
I would also recommend extreme caution with some of the prescription drugs for weight loss, especially Alli and Xenical, both of which use orlistat as their active ingredient. Among the side effects, which unfortunately aren’t all that uncommon, are rectal bleeding, anal leakage and kidney and liver problems.
I cannot think of any good reason to use these when there are so many excellent over-the-counter supplements available with much a much safer profile. Below I have given you a nice summary of the products that really work. Yes, as always, I’m trying to save everyone a lot of wasted time and money.
Keep in mind that none of these products are a substitute for diet and exercise when it comes to dropping those pounds. The list below should be looked at as an aid or a help, not as an end in itself.
And remember: be serious about losing those pounds. Those Love Handles Can Be Deadly.
CAUTION: Talk to your doctor if you have any medical conditions.
1) Irvingia. There is an interesting new weight loss supplement called Irvingia that looks extremely promising.  One study found that, with no change in diet, study participants dropped 28 pounds in 10 weeks. This is a phenomenol amount of weight loss and is doubly remarkable because those in the study continued to eat as they always ate! What is even more remarkable about this supplement is that it lowers glucose, cholesterol, LDL and CRP (inflammation). A previous study found that it also dramatically lowered triglycerides.  In other words, not only does it drop weight, which is the cause of so many health issues, but it also lowers most of the key markers for heart disease. One of the key ways that it works is by lowering leptin, which is a hormone that signals your body to basically store fat. Leptin is also key to appetite control and so this also helps moderate hunger as well. It also inhibits the amylase enzyme, which converts starches to sugars in the intestine. In other words, it seems to almost magically help virtually every metabolic pathway dealing with weight retention. The only caution that I have is that you should talk to your doctor first, of course, and realize that this is a very new supplement, i.e. there is not a lot of history at this point. It may effect digestion, absorption or any number of metabolic processes.
2) Green Tea. Several studies show that Green Tea or its extract raises metabolism, i.e. burns more calories. 
3) Caffeine. A couple of studies show good ol’ fashioned caffeine increases metabolism and calorie-burning. Don’t go crazy though as it can interfere with your Sleep and sleep can raise appetite and make you too doggone lazy to exercise among other things. 
4) Capsaicin, Green Tea and CH-19 Sweet Pepper. Several studies show this combination is a powerful fat burner with no significant side cardiovascular side effects. 
5) Capsaicin, Green Tea Extract (w/ Caffeine), Tyrosine, and Calcium. This combo was found in one European study to be a potent fat burner.  In fact, it increased daily energy expenditure by 2%!
6) Calcium Pyruvate. Most studies show this fat-metabolizing compound, if ingested in quantities greater than 6g/day, does help participants lose modest amounts of weight. 
7) CLA. Several studies show positive fat loss results.  How does this weight loss supplement work? CLA interferes with lipoprotein lipase that helps store fat in your body and even helps your body use existing fat stores more efficiently. CAUTION: One animal study showed that CLA caused accumulation of fat around the liver, potentially increasing or exacerbating insulin resistance.  Other researchers are arguing that it should be classified as a trans fat. 
8) L-Arginine. Arginine has been shown to promote weight loss. If you are not eating much meat (or nuts), you may want to consider supplemental L-Arginine. See my link on a What L-Arginine Can Do For You and Potential Side Effects.
9) Glucomannan. This is another weight loss supplement that started with somewhat mixed results because the sample size of the studies were all comparatively small. One recent meta-analysis aggregated the results and found that glucomannan was effective as a weight loss supplement.  Furthermore, similar to Invingia, this product also improves many cardiovascular makers: the study above found that glucomannan also significantly lowered triglycerides, total cholesterol and LDL. It apparently works by slowing absorption of glucose and cholesterol from the intestines. Again, you can buy this at a greatly discounted price through Amazon. For example, one well known distributor, Nature’s Way is about half off: Nature’s Way Glucomannan Capsules, 100-Count Bottle.
10) Calcium. Scientists are not sure why it works, but several studies (on women) show Calcium accelerates weight loss. For example, one study showed participants lost 4.43, 3.46 and 3.89 pounds, respectively, on high milk, soy milk and supplemenatal calcium versus 2.87 pounds for controls.  CAUTION: Guys must be careful not to have too much Calcium, as it elevates calcitrol levels, which have been linked to prostate cancer. And soy probably deserves caution as well, as it has been linked to brain shrinkage in males.
11) Water Before Meals. Okay, water isn’t a supplement. Still, researchers have recently discovered that one of the best ways to lose weight is simply to consume water before meals.  One of the triggers that tells your brain, “I’ve had enough” is weight in the stomach. Putting some water in your stomach ahead of eating satiates you much sooner than normal and helps you with appetite control.
YOUR GUESS IS AS GOOD AS MINE: Hoodia and Bitter Orange Extract have no well-controlled studies backing their claims of being a fat metabolizer and appetite suppressor, respectively. You can certainly try them but just realize it is guesswork, not science, at this point.
CAUTION: Most studies show that you should not buy Chromium Picolinate or Carnitine for weight loss, i.e. they are ineffective. These supplements do actually have other good uses, but weight reduction is not one of them. HCA is in the same category by the way: one study at least showed no improvement in appetite or weight loss for the participants.