I was watching Manswers on Spike Tv the other night, and they were talking about silver lined underwear. The British Army, or some other country's military anyway, uses silver impregnated underwear because they can go to the field and not wash it for so many weeks at a time because the silver kills the bacteria. I have also read a lot of other things about silver in clothing, and it all says the same stuff. I use some base layers that have silver in them, it seems to do a good job. I also use scent killer sprays and scent lok clothing, so I can't say what works the best, only that what I do as a whole has worked out good. I will say, however, that I noticed the most drastic improvement from using the scent lok carbon clothing.