If you’re talking about Cortislim:
I was asked to research this recently. I won’t go into the physiology of cortisol micro-regulation because it’s complicated, and in the end irrelevant. If you check the company’s website for the actual ingredients of the pill, you’ll find that have a dubious relation to cortisol levels to begin with, according to what little serious scientific literature there is on them.
Dr. [Shawn] Talbott seems to be a properly credentialed researcher, whatever you think of his theories (I have not read his books, but according to my literature searches, he has never he has not published any research in humans related to the assertions in his books*, but his relation to the Cortislim product is unclear. It is interesting that Dr. Talbott’s first name was not even revealed until the most recent series of ads, which made it harder to check his reasearch
“Dr.” Greg Cynaumon, the self-admitted non-expert “spokesman” (according to the infomercials and many press releases you’ll find by googling his name) or “co-creator of Cortislim” (according to his current website, reportedly holds a “diploma mill” PhD in psychology, and has been involved in two possible major scams in the past decade (a nationally advertised “miraculous” educational phonics game ca 1996, and more recently, an employment “scam”(?) that has been the target of government action and civil suits)
I won’t assert that that all the allegations are true. The few I verified with, e.g., CA state licensing boards and Dissertations abstracts, seemed to be accurate, but I am neither a professional investigator nor a lawyer. Here’s a site outlining the allegations. Check it out and decide for yourself.
My own background, in medicine and molecular biology, made me highly skeptical of the product. Note that it does not claim to control cortisol, per se, it simply makes nonspecific claims to somehow “optimize” various parameters if they are already normal! The {url=http://www.cortislim.com/faq.htm]Cortislim website implies that it (e.g.) stabilizes levels of certain hormones or blood sugar, but it never actually says this, or speciefies any verifiable effect.
This I can say: one documented effect of one major Cortislim ingredient is a mild calming effect, and possibly greater ease of getting to sleep. In related support groups and user bulletin boards, one often finds users who report these effects, even if they don’t observe any other. Many find this “worth the price of admission”, but this is not what Cortislim primarily promises.
I should note that an unregulated “herbal” product does not in any way indicate a "gentler"treatment with “fewer side effects”. When the active chemicals in the herb are characterized, extracted and provided at a regulated strength and purity, it becomes an “medicine” and hence “harsh and unbalancing” in the eyes of some, but at least it, its effects, side effects and any risk factors are far better known.
This is not medical advice.