Often the images show something else entirely, such as an infected hair follicle.

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Shiny, healthy hair starts with the vitality of cells in the hair follicle, where hair is manufactured, says Katz.

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Sometimes an epidermoid cyst has a central opening the remnant of a hair follicle from which the cyst originally formed that's plugged by a tiny blackhead.

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Every drop of saliva you leave on a Styrofoam coffee cup or hair follicle that falls to the floor contains DNA that in theory can be tested for everything from ancestry to disease risk.

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Common problems include overactive oil glands, bacteria growth within follicles and pores and problems with the keratinization process, where cells are normally sloughed off the skin, pushed out of the hair follicle and replaced by new cells.

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Although it is understandably tight-lipped about the exact mechanism behind its success, one probably enlists the help of cells called keratinocytes, which interact naturally with the dermal papilla cells of the hair follicle and secrete a chemical factor that supports their growth.

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Topical products can change the hair's appearance but not the follicle itself, he cautions.

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