The hair growth cycle explained: where Abundant fits into anagen, catagen and telogen
Updated September 2026 · reviewed by the Abundant Research Team. We are an independent information resource, not a medical provider, and this article is educational rather than medical advice.
The hair growth cycle is the repeating sequence every follicle moves through — a long growth phase, a brief transition, and a rest before the strand sheds and a new one begins. Understanding those phases explains why hair grows to a certain length, why a little daily shedding is normal, and where steady nutrition matters most. This guide walks through the cycle in plain language and shows where a daily formula like Abundant fits alongside it.
The hair growth cycle, in one place.
- Anagen
- The active growth phase, lasting roughly two to six years for scalp hair.
- Catagen
- A short transition of a few weeks when the strand stops growing.
- Telogen
- A resting phase of a few months, ending when the old hair sheds.
- Where nutrition fits
- A steady supply of protein, iron, zinc and vitamins helps sustain anagen.
Because each follicle runs on its own timetable, you rarely notice the cycle at work — until a season of extra shedding makes you curious. Below we break the cycle into its phases, then look at the nutrients the follicle draws on. For the nutrient side of the story, see our companion guide to vitamins and minerals for hair.
What is the hair growth cycle?
The hair growth cycle is the biological loop in which each follicle grows a strand, pauses, rests, and then releases the old hair to start again. It is not synchronised across your scalp: at any moment different follicles sit in different phases, which is why humans shed a little every day rather than all at once. Scientists describe three primary phases — anagen, catagen and telogen — and sometimes add a fourth, exogen, for the shedding step itself.
What happens during anagen, the growth phase?
Anagen is the active growth phase, when cells in the hair bulb divide rapidly and push the strand steadily longer. It matters most for length, because scalp hair grows at roughly a centimetre a month for as long as anagen lasts. At any given time the large majority of scalp hairs — commonly cited as around 85 to 90 percent — are in anagen. The follicle is one of the fastest-dividing tissues in the body during this phase, which is why it depends on a reliable supply of nutrients.
How long does the anagen phase last?
For scalp hair, anagen typically lasts about two to six years, and that duration is largely written into your genes. A longer anagen phase is what allows some people to grow very long hair, while a naturally shorter one caps length no matter how carefully the hair is treated. You cannot rewrite that genetic timetable, but keeping the follicle well supplied helps it complete the anagen phase it is programmed for.
What is catagen, the transition phase?
Catagen is a short transition phase, lasting only a few weeks, in which the follicle stops producing new strand and begins to shrink. Growth ends, the lower follicle regresses, and the hair detaches from its blood supply to become a club hair. Only about 1 percent of hairs are in catagen at any moment. It is best thought of as the follicle winding down before a rest: a normal step rather than a sign of trouble.
What is telogen, the resting phase?
Telogen is the resting phase, lasting roughly three months, during which the club hair sits in place while the follicle takes a break before starting a new anagen cycle. Around 10 to 15 percent of scalp hairs are in telogen at any given time. The old hair is eventually pushed out — the exogen step — as a new strand grows beneath it. This staggered turnover is why a certain amount of daily shedding is completely normal.
How much shedding is normal each day?
Shedding of about 50 to 100 hairs a day is considered normal, simply reflecting the share of follicles that reach the end of telogen on any given day. You will notice these hairs on a pillow or in the shower drain, and the number naturally varies with the seasons. A sustained increase in shedding, a widening part or visible thinning are different matters and worth raising with a healthcare professional, since they can have many causes. To reduce avoidable losses, see our guide to reducing hair shedding naturally.
| Phase | What happens | Typical duration | Share of hairs |
|---|---|---|---|
| Anagen | Active growth; the strand lengthens | 2–6 years | ~85–90% |
| Catagen | Transition; growth stops, follicle shrinks | 2–3 weeks | ~1% |
| Telogen | Resting; the club hair waits | ~3 months | ~10–15% |
| Exogen | Shedding; the old hair is released | Overlaps telogen | 50–100 hairs/day |
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Why does the cycle matter for hair thickness?
Hair looks fuller when a high proportion of follicles are in the anagen growth phase and fewer are resting or shedding. When a stressor — illness, crash dieting, a major life event — pushes an unusually large share of hairs into telogen at once, a heavier shed can follow a couple of months later, a pattern doctors call telogen effluvium. Encouragingly, this shift is usually temporary, and follicles generally resume their normal rhythm once the trigger passes.
Where does nutrition fit into the hair growth cycle?
Nutrition does not add phases to the cycle, but it supplies the raw materials the follicle needs to sustain the demanding anagen growth phase. Because the hair bulb divides so rapidly, it is sensitive to shortfalls. Protein provides the keratin; iron helps carry oxygen to the follicle; zinc supports tissue growth and repair; and vitamins A, C and E, plus the B-group including biotin, each play recognised roles in skin and scalp health. When these run low, research links the shortfall with more hairs shifting toward resting and shedding — which is why an adequate, varied diet is the foundation.
| Nutrient | Role across the cycle | Everyday sources |
|---|---|---|
| Protein | Supplies keratin for the growing strand | Eggs, fish, poultry, beans, lentils |
| Iron | Oxygen delivery to the active follicle | Red meat, shellfish, lentils, spinach |
| Zinc | Tissue growth and repair in anagen | Oysters, beef, pumpkin seeds, chickpeas |
| Biotin & B-group | Cofactors in keratin-related metabolism | Eggs, whole grains, nuts, seeds |
| Vitamins A, C, E | Scalp health and antioxidant support | Produce, citrus, nuts, vegetable oils |
How does Abundant support the daily cycle?
Abundant is a once-daily capsule designed to top up the everyday nutrients the follicle draws on throughout the growth cycle, not to treat hair loss or override your genetics. It combines biotin, zinc, selenium and vitamins A, C and E with pantothenic acid and iodine, plus traditional botanicals such as saw palmetto and horsetail. Real meals come first, and a consistent capsule fills the gaps that busy weeks, travel or a limited diet can leave. Taken with food, it is best viewed as steady nutritional insurance. Read the full breakdown in our Abundant review.
Support the cycle every day
Abundant pairs biotin and zinc with hair-focused vitamins in one daily capsule. The six-bottle bundle is the best value at $49 per bottle, with free U.S. shipping and a 60-day money-back guarantee.
Check today's Abundant pricing — from $49/bottleHow long before you might see a difference?
Any nutrition-related change shows up slowly, because hair only advances about a centimetre a month and new strands take time to reach visible length. A shortfall corrected today may not be apparent for several months, once fresh anagen growth has grown out. Most people give a routine three to six months before drawing conclusions, and results vary. For faster wins in the meantime, gentle handling helps — see our tips on strengthening hair from within.
The bottom line
The hair growth cycle is a staggered loop of growth, transition and rest, and most of what you see is hair quietly working through the long anagen phase. You cannot rewrite the genetic timetable that sets how long anagen lasts, but you can make sure the follicle is never short of the protein, minerals and vitamins it needs. Feed it with a varied diet first, handle your hair gently, and, if you want a convenient top-up, a daily capsule such as Abundant can help keep those nutrients steady.
Frequently asked questions
What are the phases of the hair growth cycle?
The hair growth cycle has three main phases: anagen, the active growth phase that lasts years; catagen, a short transition phase of a few weeks; and telogen, a resting phase of a few months that ends when the old hair sheds and a new one begins. Some sources add exogen, the shedding step itself, as a fourth phase.
How long does the anagen growth phase last?
For scalp hair, anagen typically lasts about two to six years, which is why scalp hair can grow long. The length of your anagen phase is largely genetic and helps determine how long your hair can get before it naturally sheds and restarts the cycle.
How much hair shedding is normal each day?
Losing roughly 50 to 100 hairs a day is considered normal, reflecting the share of hairs in the telogen resting phase at any time. Seeing more hairs than usual over a sustained period, or noticing thinning, is worth discussing with a healthcare professional.
Can nutrition change the hair growth cycle?
Nutrition does not add extra phases, but the follicle is a fast-dividing tissue that depends on a steady supply of protein, iron, zinc and several vitamins to sustain the anagen growth phase. When key nutrients run low, more hairs can shift toward resting, which is why an adequate diet matters.
Where does Abundant fit into the hair growth cycle?
Abundant is a once-daily capsule that supplies biotin, zinc, selenium and vitamins A, C and E alongside botanicals such as saw palmetto and horsetail. It is designed to top up the everyday nutrients the follicle draws on across the cycle, as a complement to a balanced diet rather than a treatment for hair loss.
How long before I might notice a difference?
Because hair grows slowly, about a centimetre a month, any nutrition-related change takes weeks to months to reach visible length. Most people give a consistent diet and supplement routine at least three to six months before judging, and individual results vary.
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Abundant is a dietary supplement, not a treatment for any medical condition. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Always consult a qualified healthcare professional about your individual needs.
References & further reading
- StatPearls / U.S. National Library of Medicine. Anatomy, Hair Follicle — Growth Cycle. ncbi.nlm.nih.gov/books/NBK499948
- National Institutes of Health, Office of Dietary Supplements. Iron — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Iron-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. Zinc — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Zinc-HealthProfessional
- Paus R, Cotsarelis G. The biology of hair follicles. N Engl J Med. 1999. Paus & Cotsarelis 1999, N Engl J Med — PubMed 10441606
- Mayo Clinic. Hair loss — Symptoms & causes. mayoclinic.org/diseases-conditions/hair-loss
These references describe the hair growth cycle and nutrients in general terms and do not constitute evidence that any product treats, cures or prevents any condition.
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