Nearly one third of men are bald, while nearly 30 million American women are losing some of their hair too. " Good Morning America" investigated an innovative new treatment that can help hide thinning hair, but what should you know before giving it a try? First of all, you should know that what you're getting is not really a tattoo. It's not cosmetic makeup either, although both of those were the jumping off point for this new invention. Good Look Ink, the company we profiled, calls it "Cosmetic Transdermal Hair Replication." Other companies call it "Scalp Pigmentation," and still more say "Cosmetic Hair Follicle Replication" or "micro hair technique." So YOU don't call it a "mistake," here are some pros and cons to consider before getting one of these treatments. While there may be variations between the treatments offered, the basic process involves getting ink marks inserted just under the skin of your scalp that look like tiny hairs. By contrast, tattooing uses a heaver gauge needle, injects ink much further under the skin and usually causes bleeding. So, that's where you should start with your questions. Read on. What kind of needle do you use? Hair replication specialists say regular tattoo needles are too thick to look like realistic hairs, so you don't want that. They say finer cosmetic makeup needles are more appropriate for hair treatments. But there is one critical detail: they say the needle should not be perfectly round. Hair follicles, when magnified, are actually jagged, irregular. Ideally the needle used to mark your scalp will mimic that. And, of course, make sure the facility uses brand new needles on each customer. What kind of ink do you use? You know how old tattoos often have that blue look to them? You definitely don't want that on your head! So make sure the facility providing your hair replication service doesn't use ordinary tattoo ink. Apparently, cosmetic makeup ink isn't quite right either because it can fade. Ask whether the facility uses an ink formulated just for the scalp. We found they are hesitant to talk about it, perhaps for competitive reasons. But you'll at least want to make sure the ink is safe for use on your head. Ask if there is a Material Data Safety Sheet (MSDS) that you can read about the ink. Look for a facility that blends a custom color to match your natural hair or a place that has a huge array of colors to choose from, so you can find a good match. And keep in mind, the process of replicating hair with ink is new, so we haven't yet seen the long-term results of how it holds up. Some companies say the ink can fade and customers may have to undergo a retreatment a few years later. Can I see the results on somebody else before undergoing treatment? In the era of photo shop, you shouldn't trust before and after pictures alone. The Federal Trade Commission, the nation's consumer watchdog, has caught weight loss companies doctoring "after" photos, so it can happen. Insist on seeing the results in person -and don't be shy, get a nice close-up look. Ideally you'll be able to see more than one past client and at least one of those people should have the same type of hair loss that you have. Can I grow my hair out later? For men, if you have the classic horse shoe of hair left, growing it out would look truly strange since the simulated hairs in your bald spot would not grow. Guys, don't go for this treatment unless you are ready to commit to the buzzed hairstyle. Since this procedure is used to mask thinning hair in women, growing it out shouldn't be an issue for the ladies. How do you find a natural-looking hairline? This is the most crucial aspect of the treatment. If the hairline is too low on the forehead it can look awful. For that reason, it's best to start with a conservative hairline. You can always add more. It's much easier to add than subtract. The ink can be removed, typically with a laser, but it is very difficult and can be painful. It's best to consider it a permanent look. Many men have just enough peach fuzz left on their heads to trace an appropriate hair line. Also make sure you choose a hair line appropriate for your age. Even men without male pattern baldness tend to see some natural rescission of their hair near their temples as they age. Women's hair loss is usually diffuse or concentrated on top of the head, at the part, so determining where to place the ink marks is easier. What if I lose more hair? Ask the treatment facility about this. Ideally, they will blend your simulated hair with your real hair by fading the ink marks into your hair. That way, if you lose more hair there will already be simulated hairs there for camouflage. Ask whether there is any problem with getting an additional treatment later, if needed. What if I want my hairline to recede naturally as I age? That is a definite challenge of this treatment. For that reason, it's smart to start out with a conservative new hairline. You can always go back for a re-treatment, if you want the hair to come further down your forehead. But once you commit, that's likely to be your look for life. What will I do when my natural hair starts to go gray? Some hair replication companies say this is not an issue for men who wear their hair close-cropped or for women, who often color their hair. But the truth is, the procedure has not been around long enough for people to really know how it will wear and how it will blend with graying hairs. Some companies say they can re-treat your scalp with a gray pigment. If you think you will want to go naturally gray some day, ask plenty of questions about this issue. Can hair replication be combined with other baldness solutions? Advocates of this treatment say they like it because it can be used to camouflage scars from hair transplant operations. It can also camouflage alopecia in which people sometimes lose distinct patches of hair. They also note that men who have been wearing a hair piece for years, can now get rid of it without having to admit they wore it in the first place! Ideally, it will just look like a guy has now chosen to buzz off his hair. Is sun exposure a problem? Yes, it can be. Centers that provide this treatment say UV rays can affect the ink. They urge customers to wear sunscreen or a hat if they will be in the sun for a long time. And since nobody knows how the ink holds up over decades, this is an issue to consider carefully. Is it safe? Since the procedure is so new, there's not much, if any, data on whether people have suffered side effects. So the best we can do is compare this hair replication procedure to its closest relatives, permanent makeup and tattooing. The two main health concerns with those are the cleanliness of the needles and the possibility that you could have an allergic reaction to the ink used. Ask the facility if they use brand new needles on each client. It's also a good idea to get a small patch test on an inconspicuous part of your scalp, before going in for the full treatment.