Most men and many women start experiencing thinning hair and ultimately lose hair as they age. But, what does thinning hair actually mean and why does it happen? Knowing how your body grows and maintains hair is important to make sure you are engaging in the proper hygiene to promote a healthy scalp and hair follicles. Read on to learn everything you need to know about thinning hair.

Hair Anatomy and the Growth Cycle

Let’s start with some basic medical information. Hair follicles are skin organs shaped like tiny cavities from which hair grows, and at the base of each follicle is a hair bulb. There are over 100,000 follicles on a full discussing the science of thinning hair like thishuman scalp serving to anchor hair into the scalp. Cells in the hair bulb grow and divide to create your hair strands, which are made out of the protein keratin. Stem cells tied to the follicles keep hair follicles in good working order. This process is regulated by numerous genes, all of which contribute to differences in the color, diameter, count, and appearance of your hair.

Three phases describe the growth cycle of hair for a specific follicle: anagen, catagen, and telogen. In the anagen phase which could last up to 7 or so years, hair begins growing from a root at the base of the follicle, and can grow for several years when nourished well by blood vessels at the base of the follicle . At some point toward the end of this phase, a new phase begins (catagen phase). In this phase, hair growth slows and the follicle starts to reduce in size. In the final telogen phase, the hair stops growing completely, falls out, and new hair begins to emerge from the base of the follicle, beginning the three phase growth cycle again. Hair typically grows at about half an inch per month.

When Your Body Turns On You

The hair growth process works really well until it doesn’t. Don’t blame your hair though . . . outside factors often start mucking up the works, and the result is what is called miniaturization. When hair follicles are not well nourished, attacked by hormones (e.g., DHT), ravaged by age and stress, or otherwise bothered, the result is often a progression to a thinner, colorless hair strand that may fall out completely over time. In short, the hair follicle shrinks, the anagen growth phase shortens, and the resulting hair just isn’t as strong or prominent as it used to be. Thinning hair becomes more noticeable everyday, and the follicle ultimately will die and cease to grow any hair.  Pigment cells which produce melanin to color your hair also die over time, leaving your hair gray.

The good news is that different follicles are in different stages of growth, and some are more sensitive to outside influences than others. For example, hair around the horseshoe area of your scalp are less sensitive to DHT, a major cause of miniaturization. Follicles in this area are often those used for transplantation to thinner areas of the scalp.

Curing Thinning Hair

Knowledge of the hair growth cycle and the concept of miniaturization are essential for developing and seeking out a cure for thinning hair. The most effective hair loss treatments attempt to avert miniaturization by blocking toxins from reaching the follicle (whether that toxin is a hormone or simply stress-induced), nourishing or increasing blood flow to the follicle, or replacing dying follicles with others resistant to miniaturization. Elongating the growth (or telogen) phase of growth is necessary for ensuring strong, vibrant hair.

Myths about what causes or cures hair loss also are easier to identify if you understand the process of hair growth. For example, hats do not cause hair loss, which is clear if you understand that the follicle is nourished from underneath it, not above it.

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