There are many misconceptions and curiosities about eyelashes and their growth cycle, and I'm here to help you learn a little bit more about eyelashes.
The upper eyelid has approximately 90-150 eyelashes on it, while the bottom has between 70 – 80 eyelashes. Most eyelashes grow to be about 10mm long, just over 3/8 of an inch.
HAIR GROWTH CYCLE
Even though it may not seem like it, every hair on your body has a growth cycle. It will grow to a specific length and eventually reach its full cycle, and then fall out. There are three phases to all hair growth cycle, even eyelashes:
Anagen (Active Growth Phase) Hair is still attached to the Dermal Papilla (blood supply). Only 40% of the upper eyelashes are in active growth at any one time (only 15% of lower lashes are in active growth). This phase lasts 30 – 45 days or 4-6 weeks.
Catagen (Transitional Phase) During this phase, the eyelash stops growing and the follicle shrinks. This lasts 2 – 3 weeks.
Telogen (Resting Phase) This phase can last over 100 days before the eyelashes fall out.
Each eyelash is in its own cycle so there are some lashes in each phase at all times and most days at least a few eyelashes will fall out.
DO EYELASHES GROW BACK?
Yes they do, but it might take a couple of months before you see them especially if you have interrupted the natural growth cycle in some way. For example, if you pull your eyelashes out, you will be without any visible eyelashes for a while before they grow back and get to the resting phase (telogen). If you have been pulling your eyelashes out, the hair follicle still has to finish its growth cycle. A new one will not grow in any faster, since the other hair was prematurely removed. Thus, potentially creating a less than full look for a while. No fear for there are many different lash serums to help nurse your lashes back into shape!
HOW LONG WILL EXTENSIONS LAST?
Typically, eyelash extensions last 4-6 weeks, it varies greatly from person to person due to their hair life cycle, skin type, environment, lifestyle and care. Some lashes will be lost within a couple of weeks as part of the natural cycle, so it is common to get a retouch after around 2 to 3 weeks. Understanding the growth cycle of an eyelash can help you understand we will never know which hairs are in which growth cycle, therefore, continually expecting a natural shedding to occur.
Down here is a cute little video explaining the eyelash growth cycle in case you are curious and want to understand more.