This study was published April 2013 in the Journal of the International Society of Sports Nutrition:

Eight weeks of supplementation with a multi-ingredient weight loss product enhances body composition, reduces hip and waist girth, and increases energy levels in overweight men and women. Full Article – free access
This study was double-blind, placebo-controlled meaning neither the scientists nor the participants knew whether they were getting the real treatment or the fake until after all the data was collected. The patients were obese but otherwise healthy (remember the “thin on the outside, fat on the inside” aka TOFI complex? Yes, you can be overweight and healthy or skinny and unhealthy).

The supplement being tested, aka the “multi-ingredient weight loss product” is composed of an interesting combo:

* Raspberry Ketones
* Caffeine
* Capsaicin
* Bitter Orange
* Garlic and Ginger Root Extracts

Here’s the label for Prograde Metabo 223X

Click Here for Label Close-Up

Metabo 223X is a weight loss supplement…
Not to be confused with Metabo power tools.

Why is this interesting? 
* Raspberry ketones were made popular by a certain daytime doctor, and there’s actually VERY little science behind their effectiveness (unless you count consumption of berries and other fruits and vegetables as being good for your health)

* Caffeine and capsaicin by themselves have been used in weight loss studies and they are both effective at speeding up the metabolism. 
 Capsaicinoids and capsinoids. A potential role for weight management? A systematic review of the evidence

* Bitter Orange might be an effective herbal treatment for weight loss but in a review of weight loss studies involving bitter orange, 2/3rds of the study participants ALSO consumed caffeine. So is bitter orange by itself effective for weight loss? There’s not enough evidence to rule one way or another.
A review of the human clinical studies involving Citrus aurantium (bitter orange) extract and its primary protoalkaloid p-synephrine.

* Ginger root extract and garlic extract show promising effects at combating obesity and the metabolic syndrome…IN MICE, RATS AND ISOLATED CELLS.

(Boy, if I had a nickel for everything that showed anti-cancer properties in an isolated cell… I’d have enough nickels to pay the guy that said “If I had a nickel for everything that causes cancer in white lab rats…”)

Let’s recap: this supplement delivers two ingredients that definitely help with weight loss and three ingredients that might help with weight loss. Is it a surprise the people who took this 5-in-1 combo lost weight? No. 

But wait, there’s more…

Safety and Purity: 
I work in the supplement industry – I KNOW there are less-than-trustworthy brands out there, but I’m optimistic about this supplement’s compositional purity and safety*.

*Details about the supplement in the published study:
 “Capsules were produced in accordance with current Good Manufacturing Practices (cGMP) in a United States Food and Drug Administration (FDA) registered facility. Prior to production, all raw materials were tested for purity and potency. A sample of the lot and batch from the placebo and METABO finished product was tested by an independent third party for label claim and was shown to be within +/- 1% to 4.3% of the actual formulation for the main bioactive ingredients.”

Every study participant went throught the diet and exercise regime, but the people who got the real pills got real results (as in statistically significant) compared to those who got the dummy pills. In the science world, we’d say, “Yeah, it really works.”
So what’s the catch?
This supplement seems promising. In a well-designed study it gave not just good results, but statistically significant results. This “statistically significant” business is rather elusive in these kinds of scientific studies. That’s why scientists have to use the word “may” so much (“ABC may reduce your risk of XYZ”). This study was published in a fairly respectable journal, so that’s another good sign. Furthermore, the marketing message for this supplement is wellwritten by a guy who claims he’s a Registered Dietitian (becoming a RD is difficult so I always ask to see a diploma). 
Prograde Nutrition RD knows his stuff! Promo for Metabo 

The catch is this supplement is not magic. It’s not the combo of the 5 ingredients, it’s the combo of the pills, a calorie-restricted diet and an exercise program*. 

*Exercise Program Details:
 “Subjects performed three, 60-minute exercise sessions per week using a ‘boot camp’ type of training. A typical class consisted of the following format: 10 minute warm-up (i.e. walking, light jogging, or biking); 30 minutes of circuit training (upper and lower body each session) composed of the following exercises: mountain climbers, squat thrusts, jumping jacks, squat kickouts, walking lunges, push-ups, dips, resistance band elbow flexion, extension and shoulder presses; 10 minutes abdominals/core, and 10 minutes cool down/stretching. Based on pilot data monitoring heart rate, this type of training expends approximately 300-400 kcal/session.”

Obesity is caused by multiple factors, so it’s not surprising it would take multiple strategies to achieve a healthy weight. The trick is to knowing which combination of strategies will work for you.