Posted by Cam W. on June 1, 2001, at 22:42:49
In reply to Cam W. question, posted by Sulpicia on June 1, 2001, at 17:57:15
Sulpicia - I am not up on my amino acids. I do know that some of them do have active transport mechanisms into the body, but most are broken down in the stomach and reassembled into what is needed in the body. I do know that the passage of amino acids into the brain usually does require an active transport mechanism for certain molecules, including amino acids. The blood brain barrier is very selective about what it lets in. The BBB will allow serotonin's precursor, tryptophan to cross, but not serotonin itself. The tryptophan is then converted to serotonin in the brain.
The body can only use what it needs. Yes, nutritional supplements and vitamins may help in cases where there is a deficiency of these molecules, which is not that often in developed countries. Taking extra does not make the systems they work in any more functional, just as putting two refills in a pen would not make you write better.
Some nutritionalists would disagree, especially those selling these products. I believe that the FDA (or is it NIH) has a position paper on megavitamin therapy and the gist is that megavitamins may do more harm than good, over the long term. I know of no scientific evidence of high doses of vitamins or amino acids that really help in any mental illness, without having deficiencies of said molecules. There have been many claims over the years, but no hard proof.
My opinion - Cam
poster:Cam W.
thread:65091
URL: http://www.dr-bob.org/babble/20010530/msgs/65122.html