If you are talking about Yohimbe, it might actually be more effective for women. Consider this:
From Girth Control: "Kucio's team gave 10 obese women 5mg 4x per day over a 3 week trial, and they lost significantly more weight than placebo (3.55 kg vs 2.21 kg). In contrast, Sax saw no effect of a high-dose (43 mg/day) in obese men."
Yohimbe acts as an alpha-2 receptor antagonist. It has similar effects as going on a low carb diet. A lot of this is presented in Lyle McDonald's Stubborn Fat Loss.
The referenced studies are here:
Kucio C, Jonderko K, Piskorska D. Does yohimbe act as a sliming drug? Isr J Med Sci1991;27:550-6
There have been other papers and studies that show how alpha-2 adrenoceptors antagonists such as Yohimbe can help with fat loss but actual studies to compare losses is small. So a lot of it is speculation or "Why things SHOULD work"
As we know, not everything works in practice as it logically should.
From my personal anecdotal experience, I like Yohimbe. But at the end of the day, thermodynamics still reigns supreme in overall fat loss or muscle gain.
