Guarana (aka Guaranine): Guarana is a bean from South America that contains roughly twice as much caffeine as coffee beans
Rhee SJ, Cho SY, Kim KM et al (2008) A comparative study of analytical methods for alkali-soluble -glucan in medicinal mushroom, Chaga (Inonotus obliquus)
So some of the more refined current fully being developed drugs are like these fat loss appetite suppressing agents with concurrent thermogenic properties for energy expenditure and then muscle preservation mechanisms built in that inhibit myostatin or act through other pathways to try and keep the muscle on you
Look for third-party testing, clinically effective dosages, bioavailable forms of nutrients, minimal fillers and transparent labeling
& Xie, Y
Together they create a pattern of growth hormone activity that mirrors what your body produced naturally in its prime clean, controlled, and built around your biology rather than overriding it