We look at our eyelashes in the mirror. They always seem to have been there. They always look the same. But, in fact, not one single eyelash you can see in the reflection in your bathroom mirror existed more than four months ago. Each one of them is been born, grows to maturity, lives its brief life flickering on the edge of your vision, and then dies and falls out – all within, on average, 90 days (three months). You never really notice the change because they are constantly replaced by new ones.
This is very different from the hairs on your head, which grow and grow and grow. The reason why your eyelashes and eyebrows don’t grow as long as the hair on your head, is their relatively short life span.
Each eyelash grows out of a hair follicle. Its life is described as having three phases. First comes the ‘anagen phase’. This is when the hair grows in the hair follicle and comes through the surface of the epidermis (the top layer of your skin). For the first two weeks of growth, they are far too weak to take eyelash extensions. After about two weeks, they enter the ‘catagen phase’ which lasts for about another two weeks. Finally, there is the longest phase – ‘the telogen phase’ – during which the eyelashes are fully grown and mature. This period lasts for about a further 60 days (two months). There is no growth during this period. Finally, the mature eyelash falls out at the end of its life cycle. Meanwhile, a new anagen phase hair has begun to grow in the hair follicle and takes its place in a new cycle.
During the catagen phase, the eyelashes are still growing, but they are generally strong enough to take an eyelash extension. Lashes in the telogen phase are also suitable for eyelash extensions, although those at the end of their life range will fall out more quickly than others. (Unfortunately, it’s impossible to tell how new or old these mature lashes are.)
Because of this natural cycle, it is inevitable that some of the lashes chosen for extensions will fall out quickly, and in the process take their eyelashes with them. For that reason, it is necessary to have infills every 2 to 3 weeks. By that time hairs which were in the anagen phase two or three weeks previously – and which could not support extensions – have now entered the catagen or telogen phases and can now support eyelash extensions. Generally, the new hairs will be sufficiently spread along the eyelash line so that the eyelashes will still appear regular and complete after the infill process.