Quote Originally Posted by StephL View Post
Thanks for citing NyxCC - this is such an important thing to know, that physical exercise boosts the brain - just as meditation does.
And - I like your speculations Canis - got to give this some deeper thought, later.
The blood-brain-barrier has it´s own breed of transporters over this barrier - but it would make sense, that more does pass, when more is on offer so to speak.
I try to read up on it!
Cheers for that!
Hey Steph! Thanks, and you are right on the money thinking about the BBB here. That's so important when considering how any supplement or activity might affect neurochemistry.

If you're interested in further reading, most of my speculation is based off of the effect that carbohydrates have on serotonin levels. This is generally agreed to be the cause for what in the United States we call "Thanksgiving sleepiness". Basically, after everyone pigs out on Thanksgiving day, they generally feel really sleepy and a lot of times wind up napping in the afternoon.

This is due to the effect that carbs have on transport protein availability, which is similar to the effect I'm speculating about. MIT did a great study on this: Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios

Dietary carbohydrates produce major, insulin-mediated decreases in the branched-chain amino acids but lesser reductions in plasma tryptophan, thus raising the plasma tryptophan ratio (6, 9, 10) and facilitating tryptophan’s entry into the brain (13).
Anyway, if this is something you're interested in, this paper does a good job of covering some of the issues around how transport proteins can affect serotonin levels in the brain.