"The groundwork of all happiness is health." - Leigh Hunt

Don't you say? Hair gone today, yesterday.

Why does your hair turn gray and fall out with age? To answer these questions, you first need to grasp some hair basics.

Hair consists of two parts: the follicle and the shaft. Hair follicles are just under the surface of the skin. A hair shaft is what we often consider as a hair strand.

Fun fact: Hair shafts are mainly dead cells that contain the protein keratin—the identical protein present in nails, feathers, claws, and hooves—in addition to the pigment melanin, which provides hair its color. Each shaft accommodates about 10% to 13% water.

You are born with the biggest variety of hair follicles in your life. You don't grow much as you age. For the typical person, this ranges from about 100,000 to 150,000 hair shafts.

So why gray and bald? It has to do with genes, hormone decline and aging. These aspects eventually program hair follicles to stop producing pigment (causing gray hair) or to stop producing hair (causing baldness). It varies in speed and intensity, which is why men's heads can range from coarse salt and pepper to Mr. Clean.

Bottom line: You can't stop your hair from changing. It will do what it's destined to do.

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