When your hair follicles are dead, they do not regrow hair. You can inspect your scalp and look for signs of hair growth. Even if you only see thin hair patches or fuzzy texture, your hair follicles are still alive and will continue to renew themselves.
Dead hair follicles are most evident when the scalp's skin (where the hair once grew) becomes smoother and shinier in appearance. In other words, there'll quite literally be no hair there/no signs of regrowth if your hair follicles are completely dead.
If the hair follicles are at an initial stage of damage, the growth phase of hair can come back. However, if it has been a long time since the hair follicles have been dormant or have died, there stands a rare chance of reviving them.
When hair follicles don't get enough nutrients, they can thin and eventually this can lead to hair loss and baldness. This may be due to the resting phase in the hair cycle when new hair growth stops for a time. But if the follicles die then hair growth will stop completely.
There are a variety of methods available for the regrowth of hair follicles, from using medication to massaging your scalp to stimulate your hair directly. Currently, the most effective way to reactivate your hair follicles is by using medication, such as finasteride and minoxidil.
In addition to kickstarting your follicles through targeted scalp massages, certain topical hair-care products like serums and scalp cleansers can help prompt your follicles to get back to work. They contain ingredients that, when applied directly to your scalp, work to stimulate and nourish your follicles.
For most people, the most obvious sign of hair follicle damage is hair loss. As your follicles become damaged, they may stop growing new hairs, resulting in a receding hairline, bald spot at your crown (the area at the top of your head) or diffuse thinning.
It can only restore existing hair growth and cannot reactivate dead follicles.
The active growth phase of hair lasts 3–10 years. Catagen. The transition phase where hair stops growing lasts 2–3 weeks. Telogen.
Then is the telogen or resting phase. The follicle becomes dormant for around 1 to 4 months. The club hair that has been formed keeps the hair in the follicle for several months, but the hair is no longer in anyway alive or growing.
Minoxidil. One very good medication to reactivate dormant hair follicles is minoxidil. Applied regularly to the scalp, minoxidil can re-grow hair that has completely stopped growing. The only caveat is that once you start taking it, you'll have to keep taking it indefinitely.
There are a total of one million on the head, with one hundred thousand of those follicles residing on the scalp. This is the largest number of hair follicles a human will ever have, since we do not generate new hair follicles anytime during the course of our lives.
If you damage your hair follicles after an injury, they can repair themselves and your hair will grow back. It could take up to four years before you see new hair growth out of damaged hair follicles, depending on the severity of your injury.
“Some ingredients that stimulate growth are herbs like saw palmetto, horsetail, and vitamin B3,” Stevens says. “Oils like coconut oil, vitamin E oil, pumpkin seed oil, peppermint oil, rosemary, tea tree, and thyme oil are additional options.”
“If a follicle has closed, disappeared, scarred, or not generated a new hair in years, then a new hair wouldn't be able to grow,” Fusco says. But if the follicle is still intact, yes, it is possible to regrow the hair—or to improve the health of the existing thinner hairs.
Hair drug tests have the longest detection period, and can typically detect drug use for up to 90 days. Depending on the drugs used, a hair sample can sometimes help determine when drug use occurred and whether it's been discontinued.
As long as it is not happening excessively or you are not noticing it on every hair strand that falls out, losing hair with a bulb at the end of it is perfectly normal. It just means that you lost the hair in the third phase of the hair growth cycle rather than during the fourth phase.
Heat causes sweat. Both can cause clogged hair follicles and make them worse. Keep your body temperature down by drinking plenty of water and staying indoors when you can. If certain bacteria get into your hair follicles, it can clog them.