We are born with roughly 100,000 follicles on our scalp. We cannot regrow or generate new follicles after birth so what we are born with is what we have. Follicles create hair from stem cells that sit near the follicle and produce a new hair bulb (the white part located at the root end of a shed hair and is released with the hair). Over time, we lose follicles through factors such as age, hormone, or genetic follicular miniaturization or scarring disorders that destroy the abovementioned stem cells.
Blondes have roughly 20% more follicles than brunettes and redheads have about 20% fewer follicles. Asians and African Americans have fewer follicles and lower hair density than Caucasians. The follicles on the scalps of Caucasians and Asians are straight. The follicles curl and are on a greater angle on African American scalps. This curled follicle is the reason follicles are more difficult to harvest for hair transplants in African American patients.
Follicles cycle through three natural cycles, a growth phase, a rest phase, and a fall out phase, medically referred to as anagen, catagen, and telogen phases, respectively. Each follicle individually cycles through these three phases independently of each other. Of those ~100 000 follicles, 85-90% are in anagen, <1% are in catagen, and 10-15% are in the natural fall out phase, telogen. Follicles stay in the anagen growth phase for 2-6 years, catagen for 2-3 weeks, and telogen for 3 months before the hair is released from the follicle. Applying these numbers, you will shed on average 100-200 hairs/day. If these hairs are collected, it can appear as a large amount of hair but be reassured that a fresh new anagen hair helps to push out that old telogen hair and a new follicle cycle begins.
Anagen follicles grow scalp hairs at a rate of 0.35cm/day or roughly 1cm/month. This rate may increase with medications or pregnancy and decrease with age, nutrition, medications, and illnesses. Follicles only create hair in anagen growth phases. Therefore, hairs only grow in anagen phase, so follicles in the catagen and telogen phase only rest and fall out, respectively. The maximum length is greatest at the end of anagen phase with the exception of breakage which can shorten hairs. Proper hair care can help maintain length retention. Moisture regimens can be found at http://www.DrHillHairLoss.com/?p=73.
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This is the season to winterize your hair. Dry frizzy hair happens during the winter due to the constant change from cold outdoors to heated indoors. We will discuss preparing a winter regimen and ways to maintain moisture in the hair without causing excessive drying which may lead to split ends, breakage, and loss of length.
- Drink plenty of water. Water evaporates from your skin and hair at an increased rate during the winter due to heat/furnaces.
- Wash hair weekly or biweekly to remove debris and product build up which can lock out moisture.
- After washing hair, seal in moisture with a light oil, such as argan or coconut oil. Make sure to pay special attention to the ends which have received the most wear and tear on the entire length of your hair.
- Apply a light cream or light-weight non-oily hair lotion daily to add moisture back into the hair. Lotions and cream contain a higher water content compared to oil and grease. Also avoid alcohol-based products during the winter which can further pull water out of the hair.
- Take a chemical vacation (from coloring and other chemical processes) if possible (relaxers should be continued every 6-9 weeks to prevent increased breakage at the line of transition). Chemically-treated hair deserves extra TLC as the pH and chemical structure of the hair has changed. Bleaches, alcohols, peroxides are ingredients to avoid during the winter as they can make the hair brittle and cause split ends.
- Performing deep conditioners under hooded caps bimonthly or protein treatments once monthly are optimal and will help baseline moisture.
- Add water back to the hair. If you don’t want to add product that will leave residue on the hair try spraying plain water (can add lavender and a drop of your favorite oil or a drop of glycerin which helps with slippage and prevents tangles) on the hair. This is also a nice way to put moisture (which plainly is water) back into the hair midweek without having to wash.
- Try to not add products to the scalp which can coat the scalp and allow a yeast, Malasezzia, to flourish and cause dandruff. If you find yourself having to co-wash more often to retain moisture, it may mean you have to incorporate moisture using a daily regimen to maintain moisture from wash to wash.
- Your salon may offer the service of steaming the hair which can help open the cuticles and allow moisture back into the hair prior to adding products and styling. If you’re low on funds you can just sit in a bathroom with the shower steaming or hold your head over a sink or tub of hot water. There are also home steamers you can purchase for use.
- Wear protective styles such as ponytails, buns, braids, pinups, etc to prevent the ends from being traumatized and subsequently forming split ends.
- Protect thermally-treated styles by apply leave-in conditioners, use thermal protectant sprays (allow it to dry first), and try to curl, press, or straighten hair once weekly. The frequent use of heat further dries hair out further (think of it like making a grilled cheese without butter. If you throw the butter-less sandwich back on the grill it will burn). Also try to run as few passes through the hair with the iron as possible.
- You can pin-curl or re-twist between heated treatments to help maintain curly styles or wrap the hair to prolong straight styles.
- Sleep on a satin/silk pillowcase or use a satin bonnet or hair wrap. This keeps the moisture in the hair and prevents hairs from snagging on the fibers in pillowcases.
- If you are wear hats, try to find ones with a liner or wear a satin bonnet or scarf to prevent the hat material from pulling out moisture from the hair.
- Seal split ends that may occur with a thicker hair balm to allow the pieces to adhere to one another until you can get a trim. You can trim individual ends if you have a few. Otherwise, rely on your hair professional for routine trims.
Protect your strands from the elements of nature. Maintaining the moisture content at an equilibrium during the winter will allow you a smooth transition of healthy shiny hair into the summer.
Have you found any regimens that help keep winter dryness from your tresses? Share below.