10.2 Hair Growth Cycles

NIC Scientific Concepts I.G will not ask you to time a wax pot in this section. It will ask you which phase the hair is in. A classic national stem says the hair is actively growing. That phase is anagen. Illinois 1175.835 still expects you to know this science before you practice tweezer, depilatory, and wax methods in the 500-hour block, because the cycle — not the brand of wax — decides how much hair you can extract today and why the client must return.

Each follicle runs its own clock. Neighboring follicles are not synchronized. Textbook teaching calls this mosaic (asynchronous) growth. At any moment some hairs are growing, some are shrinking, and some are resting. That is why a single wax never produces a permanently bare lip, and why promising “one visit, all gone” is a science error as well as a sales error.

Anagen, Catagen, Telogen

Standard esthetics teaching uses three phases. Some medical texts add exogen (the actual shed) as a fourth name; NIC-style items still expect anagen, catagen, and telogen.

Those clocks are typical teaching ranges from standard esthetics textbooks. They are not Illinois statutory numbers, not NIC published item keys, and not an excuse to invent “exactly 21 days” as a law. Duration varies by site, age, hormones, ethnicity, medications, and health. Use the ranges to compare face versus body, not to quote fake precision.

Anagen — hair is actively growing

In anagen the onion-shaped bulb is wrapped around the papilla. Blood supply is feeding mitosis. The shaft is pigmented (if that follicle makes melanin) and is anchored by the root sheath. When you epilate an anagen hair you often see a gelatinous bulb and sheath on the end — that is the client’s “root.” Waxing is most effective in anagen because you are pulling a fiber that is still connected to the living matrix assembly. You still do not destroy the papilla. You empty this cycle’s hair. A new anagen will start later unless a method that is not Illinois esthetics (electrolysis, medical laser) is used under the correct license.

Linear growth during anagen is often taught as about ½ inch (about 1.25 cm) per month for scalp hair. Length is mostly a function of how long anagen lasts. That is why scalp hair can become long (anagen measured in years) and eyebrow hair cannot (anagen measured in weeks).

Catagen — follicle shrinking, disconnecting from the papilla

Catagen is the brief transition. Growth stops. The follicle involutes. The hair loses its connection to the papilla and becomes a club hair. If a stem says the follicle is shrinking and the hair is disconnecting from the papilla, the answer is catagen, not telogen and not anagen. Because the phase is short, only a small percentage of hairs sit here at once (scalp teaching is often about 1–2%).

Telogen — resting and shedding

Telogen is rest. The club hair may remain in the follicle for months, then shed. A new anagen hair is already organizing below. Epilating a telogen hair can feel “easy” because the club is loose; it does not reset the new germ the way an anagen extraction does. On a healthy scalp, roughly 80–90% of follicles are taught as anagen, about 10–15% telogen, and a sliver catagen, with about 50–100 hairs shed per day as a normal telogen exit. Body sites reverse that picture: a minority of hairs may be in anagen at once.

Face Versus Body — Typical Teaching Ranges

Use this comparison on the exam. Do not memorize a fake decimal.

• Face (upper lip, chin, brows): shorter anagen (typically taught as about 4–16 weeks on the lip, about 4–8 weeks on brows). Some facial zones are taught with a higher anagen fraction (chin and lip often around 60–70% in older electrolysis/esthetics tables). Faster cycling + more hairs growing = more frequent cosmetic removal, commonly taught as about 3–6 weeks between facial waxes.
• Axilla / bikini (typical tables): anagen on the order of about 4 months, with only about 30% of hairs in anagen; recare often taught around 4–6 weeks.
• Legs / arms: longer total cycles and a large telogen fraction (legs often taught near 20% anagen, anagen about 4–6 months). Recare is commonly taught around 6–8 weeks. You physically cannot clear every follicle in one appointment because most of them are not in anagen today.
• Scalp: longest anagen (about 2–6 years). Illinois esthetics does not treat the scalp as a hair-removal or coloring site (3A-1 colors except the scalp; 1175.835 massage excludes the scalp). Know the scalp numbers to explain why head hair is long, not to wax a scalp.

The chart below uses those typical teaching percentages in anagen, not measured clinic data for one client.

Why Waxing Is Most Effective in Anagen — and Why a Series Is Required

Two sentences win the item:

1. Anagen hairs are still attached to the papilla, so an against-the-grain pull can slide the fiber out with the bulb instead of breaking it at the surface.
2. Only a fraction of hairs are in anagen on any day, especially on the body, so you schedule a series. New anagen hairs surface after the last visit; telogen clubs that you missed or that shed later are replaced from below.

That is also why a client who waxes only “the day before an event” and never returns will always see stubble on a body of mixed phases. It is not proof that wax “doesn’t work.” It is mosaic cycling. Depilatories (surface keratin dissolution) and shaving ignore phase entirely — they cut or dissolve what is above the skin — which is why they have no anagen advantage and why they are temporary by design. Procedures and safety for those methods are Chapter 16; the science reason sits here.

Telogen Effluvium Is a Referral, Not a Waxing Diagnosis

Telogen effluvium is a medical shedding pattern: a larger-than-normal shift of follicles into telogen after a systemic shock, with hair coming out in handfuls about two to three months later. Classic textbook triggers include high fever, surgery, childbirth, crash dieting, a new medication, or severe psychological stress. The pattern is diffuse, not a coin-shaped bald patch (that is a different referral: alopecia areata). The client may describe a suddenly full brush, a widening part, or a frightening shed after a hospital stay.

225 ILCS 410/3A-1 lets you remove superfluous hair for cosmetic purposes. It forbids treatment of disease and forbids rendering advice on what is appropriate medical treatment for diseases of the skin. Telogen effluvium is not “waxed too much,” not “the product is too strong,” and not something you diagnose from a lip strip. You do not wax an inflamed or diseased scalp (and scalp hair removal is not your curriculum lane). You refer to a physician or dermatologist. You may still, after a medical evaluation and on intact skin, perform ordinary cosmetic facial waxing if there is no infection, no inflammation you must refuse under 1175.115, and no physician instruction to wait. The exam trap is the candidate who “treats” shedding with a depilatory or who tells the client she has a thyroid disorder. Name the phase. Do not name a diagnosis you are not licensed to make.