This thing has had pretty good reviews, seems to work in a similar way as Michael describes above, though probably less direct.
http://www.resperate.co.uk/I bought it for my folks about a year ago, though as far as I know it still not been taken out of its packaging so cant give any sort of personal account.
Though, I think you should be able to achieve similar results with good meditative relaxed breathing practice.
Also, Beetroot juice is quite good, works very quick, though I don't think its a viable long term solution as I don't believe it addresses the underlying cause.
https://www.bhf.org.uk/ThinkFit/resourc ... press.aspxIf your going to try it, bear in mind that 100% pure beetroot juice is not recommended and should be mixed to at least 1/9 proportion with water or fruit juice (apple or carrot work well). Dont know about LA, but we get this mix bottled and organic in shops, it can be a bit pricey though.
"All around, dude, try to imagine cold, cause the van is kinda hot, wrap the rat in tacky coat" - Duke Duke