I took a Nutrition, Exercise and Energy Metabolism course in University. One section talked about all types of weight loss pills. We actually got into the "medical" ingredients, which physiological pathways they are supposed to affect, and looked at some empirical, published studies conducted on the pills vs placebos.

When we got to ephedra, specificall the ECA stack, we looked at the different pathways that each of the components (ephedra, caffine and aspirin) are supposed to work on. Basically the ephedra speeds up your SNS (your "fight and flight", heart-rate increasing system) while caffine and aspirin block the PNS (the "rest and digest", heart-rate decreasing system). End effect, increased heart rate and decreased ability for your body to reset your heart rate to normal. Side effects of increasing SNS, decreased appetite. Why? Evolutionarily it wouldn't have benefitted our ancestors to get really hungry while running from a lion.

After learning the physiological principles of the ECA stack, we looked at case studies that resulted in the ban of ephedra. (Mostly) inactive, over weight people already predisposed to heart disease and hypertension, taking ephedra in various forms to lose weight. Of course, they were having heart attacks, strokes etc. But they were predisposed to those conditions. Looking at a study using ECA and young, healthy 20-30year old males, resting heart rate, on average, increased about 20bpm from an average of 70 to an average of 90. 90, while considered above average, isn't dangerous. But these males had healthy hearts, and no predisposing heart conditions.

Next, we looked at a few weight loss studies involving the stack. On average, people lost more weight than those taking the placebo. Even on a very calorie restricted diet (1000cals +/- 200cals) people were still losing weight. Basically they concluded that ECA does induce weight loss by increasing BMR. We didn't look at anything regarding long term use of the stack (the studies we looked at lasted about 6 weeks), or weight change after termination of the stack.

The science does point to ECA being an effective weight loss aid. But it is dangerous in certain populations.

So, that christmas, I thought why not? I was a fairly healthy person so I wasn't too worried about the side effects some experienced. I ordered ephedra (you can still get it online, disguised as asthma medication) and did the whole stack, while eating not a whole lot. My justification was "nothing else is working". Looking back, BULLSHIT nothing else was working! I was eating too much, not exercising enough. Period. Anyways, the "recommended dose" for the ECA stack is 3x day. So I started. First of all, I couldn't sleep anymore. And I took my last round at about 5 in the evening. Still had me going a mile a minute at 12. I didn't want to eat much, but I was having horrible heart burn that I get when I don't eat enough. I was gittery, all the time. And not the "I have so much energy I can't sit still". I definetly would plunk my butt in front of the TV, but I would sit there and shake. I didn't have an increased desire to work out, or use that extra energy productively. I couldn't focus, literally. I'd try to read emails, and my eyes would go in and out of focus. It was as if, like my hands shaking, my eyes couldn't stay in one spot for long. I could only handle it for 6 days. I lost 3 pounds in those 6 days. Did I change shape? No, so I doubt it was fat loss. Would I have lost weight/fat if I had stuck with it? Probably. Would I have put it back on after I stopped it? Probably. Like I said, I didn't increase my time the the gym, or eat healthy, just less. Nothing to indicate long term, lifestyle changes.

You, if you're healthy to begin with, probably aren't going to have a heart attack while doing a stack. Are you going to feel good while taking it? Who knows. All I know, from personal experience, I felt like shit while taking it for less than a week. I feel 100x better hitting the gym hard, and eating a yummy spinach and shrimp salad after. As Steve (sort of) said, there is a proper use for thermogenics (like ephedra) which some people do. I am far from qualified to make a judgement of what "proper use" is, as I have no experience and don't know of anyone who has encorporated them into a proper routine.

Conclusion: ECA stack isn't necessarily going to cause heart attacks and other adverse, acute health problems in healthy populations. Studies indicated that it will induce weight loss. But, in most cases, it is a lazy cop-out for people not willing to put in hard work into their weight loss. And I would guess, as with most quick fixes and fad diets, once the person stops using the stack, the weight will return.

Sorry this got so long I hope at least some of it was informative.

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