Caffeine Shampoo for Hair Loss - Does it make hair grow faster?

Paul Farrant: Margaret, thank you for clearing that up. And last but not least. Speaker 1: Hi, My name is Sunita Parkinson, and my question is about hair. There has been a trend in recent months for shampoos infused with caffeine, they claim to strengthen hair and prevent hair loss. I was just wondering what the science is behind this theory, what effect caffeine has on the hair and scalp. PF: Questions we put to Dr. Paul Farrant, consultant dermatologist at Brighton Sussex University Hospital Trust and a specialist in hair loss. Speaker 3: Shampoos, very rarely stay in contact with the scalp for any length of time. So any active ingredient has to be on contact with the skin for usually minutes for it to have any effect. The question then is whether caffeine as an ingredient has anything other than normal cleaning properties. There is some research using lab based in-vitro study, so this is growing artificially hair follicles that has shown some benefit of adding caffeine, and that seemed to reverse any negative effect of testosterone, which slows down hair growth and actually showed a slight benefit. But in-vitro conditions, they are grown for days, because you have to calculate whether the hair is growing so it takes a number of days to see that change. The hair follicles are bathed in solutions and the hair follicles bathe continuously for a number of days. So, that's not going to be the same situation as applying a shampoo that maybe, if you are very lucky on the scalp, for a couple of minutes. Speaker 3: There is a rationale that you may be able to get chemicals to absorb through hair follicles, however, in genetic hair loss and this is certainly true of male pattern hair loss, the bit that is being influenced is right down at the bottom of the hair follicle, what's called the hair bulb. So, anything applied to the surface has to be able to get right down to the hair bulb, and it has to stay there and exert an effect. It's not just a case of breaking through the skin and being absorbed into blood vessels because that would just transport the caffeine away. It has to sit around that hair bulb for probably days and used to be a continuous thing, and that's where we don't have the science. S3: So, I think there is science that shows that caffeine can stimulate hair growth in a dish. There is science that shows that caffeine can penetrate through the scalp and through hair follicles. What we don't know is whether caffeine can actually get right down to a hair bulb, stay around the hair bulb, exert a beneficial effect that will cause hairs to grow longer and thicker. I certainly wouldn't recommend buying it, thinking that you're suddenly gonna go back 10 years and have a full head of hair. There may be some slight effect, but there are no real studies...