I started taking ArginMax about 10 months ago:
http://www.arginmax.com/html/men.htm

I am 40. I didnt have a hair loss problem but in the last two weeks I noticed that I am lsing hair on top and my hairline is receding. Do you have any idea if Arginmax increases the hormone dihydrotestosterone(DHT????

I don't think it is an issue. If it raised DHT for you, you'd probably see the results before now (10 months later).

Not certain but that's my hunch, take it for what it's worth.