I am going to start off with a bold statement but one that I believe you will agree with by the time this article is done. If you want to do the best thing to get hair on a bald head the only method to look at is hair implantation. Now don't get me wrong, if you are new to the hair loss problem (you are just starting to see extra hairs on you pillow or your shower drain looks like it is growing a beard) then there are some products that will help you to keep what hair you have longer than if you did nothing.
What I am talking about is when you have already lost your hair and people start calling you chrome dome or keep asking if your head is cold. You now what I mean, all the jokes your idiot, fat brother-in-law makes about how shiny your head is. (The brother in law driving the '86 pinto). If you are tired of the jokes and you want to look youthful again then try hair implant surgery, you won't be sad you did.
Here's why this is the only method to spend any time with. If you have lost the hair on the top of your head you most likely are suffering from a medical condition called androgenic alopecia. When a man suffers from this problem his body is actually attacking the hair follicles and causing the hair shafts to fall out. I know it doesn't seem fair but that's the way it is. There is a substance in your blood, DHT, that is a metabolite of testosterone the male hormone. What happens is the DHT actually bonds with the follicles (these are also called hair roots) and cause them to stop producing the hair shaft material like they should. As the DHT continues to build up the follicle eventually is made ineffective and the hair falls out. At this point, the follicle will no longer grow hair no matter what so there is no point in even trying.
Once your head is bald, the only option is to replace the hair follicles with ones which are healthy and still growing. Luckily, you can usually get an ample number of hairs from the back of your head as that area is not susceptible to the DHT attack. The hair implants procedure gives you a full head of hair again and maybe will shut your brother-in-law up. It is sure worth a try anyway.