Skin Health Skin Care & Cleansing Products Hair & Scalp Care The Telogen Phase of the Hair Cycle What happens during this phase By Heather L. Brannon, MD Updated on March 08, 2024 Medically reviewed by William Truswell, MD Fact checked by Marcus Reeves Print The telogen phase of the hair cycle is just one part of a much larger process. You may not realize that the hair on your head, arms, face, and everywhere else on your body is constantly passing through one of four phases in a complex cycle. This article will go over what happens during the telogen phase of the hair cycle. You'll also learn how the telogen phase fits into the larger cycle of hair growth, as well as what can go wrong in the telogen phase. F.J. Jimenez / Getty Images The Biology of Hair Growth The Hair Growth Cycle The telogen phase is just one part of the entire cycle of hair growth. Growing from underneath the skin, hair extends from a root, known as a follicle. And from the time each hair starts to grow to the time it falls out many years later, it cycles through four stages: anagen, catagen, telogen, and exogen. Hair Follicle Bulb The bulb of a hair follicle is under the skin at the bottom of a strand of hair. It is how blood gets to the hair to nourish it and help it grow. If you pull out a hair and see a white substance at the end, that's the bulb. It's made of a protein called keratin that is important for healthy hair. The first phase, anagen, is the growth phase, which can last between two and six years. This phase and its length determine how long the hair becomes. The catagen phase, also known as the regression phase, comes next and only lasts about one to two weeks. During this time, the hair follicle shrinks and detaches from the dermal papilla. The third phase is telogen, which lasts about five to six weeks. The fourth and final phase, exogen, is when the hair eventually detaches and falls out. The Structure of Hair Follicles What Happens During the Telogen Phase? During the telogen phase of the hair cycle, the resting hair remains in the follicle until it is pushed out by the growth of a new anagen hair. The telogen phase is the resting phase of the hair follicle. The telogen phase lasts for about five to six weeks for hairs on the scalp and much longer for hairs on the eyebrow, eyelash, arm, and leg. At any given time, 5% to 10% percent of all hairs are in the telogen phase of the hair cycle, and up to 150 hairs are shed every 24 hours. During the telogen phase, the hair follicle is completely at rest, and the club hair is completely formed. Pulling out a hair during the telogen phase of the cycle will reveal a solid, hard, dry, white material at the root. What Is Club Hair? What Happens If the Telogen Phase Is Disrupted? Anything that disrupts the hair growth cycle can cause more hairs to enter the telogen phase. When more hair is in the telogen phase, a greater amount of hair will shed when the hairs enter the exogen phase a few months later. The excessive shedding is known as telogen effluvium (TE). While the hair loss from telogen effluvium is diffuse (spread over the entire scalp), some people may notice more loss near the front of the scalp. DermNet / CC BY-NC-ND How Telogen Effluvium Causes Hair Loss Different Types of Telogen Effluvium There are different types of telogen effluvium. They are caused by different circumstances and cause hair loss in different ways. Acute Causes of Telogen Effluvium The first is a shock of some sort that causes a temporary disruption to the hair cycle. Once the event that triggered the disruption is over, the hair follicles will return to their growing state and start producing new hair fibers pretty quickly. These events can include: ChildbirthHigh feverSudden or extreme weight lossSurgerySevere illnessSevere emotional stress Can You Get White Hair Overnight? Chronic Causes of Telogen Effluvium Another type of telogen effluvium can occur when the trigger that disrupts the hair cycle is ongoing, for example, a thyroid disorder or nutritional deficiency. Since the trigger is ongoing, the onset of hair loss is more gradual, and it lasts longer with this type of telogen effluvium Rather than a greater percentage of hairs suddenly entering the telogen phase, the hairs go into the rest phase as they normally do, but they stay in it longer. The longer rest delays the hair's return to a growth phase. Eventually, the number of hair follicles in the telogen state increases while fewer hair follicles are growing hair. The effect is a progressive and overall thinning of the hair without much noticeable shedding. What Causes Hair Loss and Thinning in Women and Men? Summary The telogen phase of the hair cylce is just one point in a complex process of hair growth on your body. Around 5% to 10% percent of all your hairs are in the telogen phase at any given moment. As many as 150 hairs are shed every 24 hours. If something goes wrong and the telogen phase is affected, you may experience a condition called telogen effluvium, which can lead to hair loss. How Telogen Effluvium Causes Hair Loss Frequently Asked Questions Can you go bald from telogen effluvium? Telogen effluvium causes hair loss but most people do not lose all their hair. It can thin your hair and you may shed a lot of hair daily. How do you reverse telogen effluvium? You can't undo telogen effluvium, but depending on the cause, it may get better on its own.If a temporary stressor caused the hair loss, you will usually start to see hair growing back over the next six months once the stress goes away.However, if the cause of telogen effluvium is ongoing, the hair loss can last for many years. Does hair without white bulb grow back? Hairs that are lost during the telogen phase usually have a white bulb on the end. If a hair doesn't have the white bulb, it usually means the hair was lost for a reason that happened above the root—for example, hair breakage. In either case, the hair may still grow. How can I reduce the telogen phase of my hair? You can't control your hair cycle, but taking good care of your hair (being gentle, avoiding heat, trying to keep it from getting too dry, etc.) can help manage hair loss from telogen effluvium and other causes. Can Herbal Remedies Slow Hair Loss? 9 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Oh JW, Kloepper J, Langan EA, et al. A guide to studying human hair follicle cycling in vivo. J Invest Dermatol. 2016;136(1):34-44. doi:10.1038/JID.2015.354 The TLC Foundation. Everything You Always Wanted to Know About Hair. Natarelli N, Gahoonia N, Sivamani RK. Integrative and Mechanistic Approach to the Hair Growth Cycle and Hair Loss. J Clin Med. 2023;12(3):893. Published 2023 Jan 23. doi:10.3390/jcm12030893 JCDR - Diffuse hair loss, Iron deficiency, Telogen hair. doi:10.7860/JCDR/2015/15219.6492 Malkud,S. Telogen Effluvium: A Review. J Clin of Diagn Res. 9(9),WE01-WE03. doi:10.7860/JCDR/2015/15219.6492 Ozlu E, Karadag AS. Telogen Effluvium. Hair and Scalp Disorders. 2017. doi:10.5772/66975 NYC Langone Health. Types of Hair Loss. S, William. Hairguard. White Bulb on Hair Follicle - A Sign of Hair Loss?. American Academy of Dermatology Association. Hair Loss: Tips for Managing. By Heather L. Brannon, MD Heather L. Brannon, MD, is a family practice physician in Mauldin, South Carolina. She has been in practice for over 20 years. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit