Doctor recommended, I guess it works, I can't really tell. I'm assuming I would probably need more blood work to be sure... I DID however ask my doctor for a less expensive alternative, as he told me that I only had to take one a day of these, and the actual recommended dosage is 3 a day. There are only 90 pills per bottle, so depending on the dosage, we are talking about the difference between a month supply or 3 month supply! I haven't had a chance to clarify THIS point with him yet... Hopefully he only wants me to take the one, otherwise I will ask him for a less expensive alternative to this brand! Like I said I don't any physical or mental health difference to make it worth it to me to justify the expense!