hair growth cycle

A recent study has shed light on the crucial role that muscle plays in hair growth. Researchers have found that the muscles in the hair sheath control the contraction of the cells that surround the hair follicles. Put simply, this contraction is crucial in the hair’s regeneration cycle.

Here, we briefly look at what the recent study found, and reveal how the natural hair growth cycle functions.

What did the latest study find?

The recent study, conducted by researchers at Mount Sinai, focused on the role of the muscles in regulating the hair growth cycle. Researchers discovered that the drastic changes that occur in hair follicles during the regression phase are coordinated by the contraction of the dermal sheath smooth muscle.

The study found that the key activating mechanism of the sheath contraction is space- and time-controlled endothelin signalling. Endothelin-1, a small protein that constricts blood vessels, is produced by cells known as progenitors located in the outer layer of the skin surface.

Endothelin signalling in dermal sheath cells and the contraction that follows, are regulated by calcium levels in the cytoplasm through channels in the cell membrane.

It was revealed that medications which block both endothelin receptors ETA and ETB, or removal of gene expression with genetically modified DNA in mice, impede dermal sheath contraction and halt follicle regression. The findings of this study could have potential implications for the treatment of hair loss.

Understanding the hair growth cycle

The hair growth cycle is a series of stages that a hair follicle goes through to produce new hair. It starts with the anagen, or growth phase, where the hair follicle actively produces new hair and grows at a rate of about 6 inches per year. It lasts for around three to five years on average.

Next comes the catagen phase, which is a brief transitional stage that lasts only about two to three weeks. During this phase, the hair follicle shrinks and detaches from the blood supply, signalling the end of the growth phase.

Finally, there is the telogen and exogen phase, which is the resting and shedding phase. The hair follicle remains dormant, and the old hair falls out. It lasts about three months before the cycle begins again.

It is important to note that not all hairs on the scalp are in the same stage of the growth cycle at the same time. Instead, different hairs are in different stages, which is why we do not typically see large amounts of hair loss all at once.

How to protect the hair during each stage

Keeping your hair healthy during the different stages of the growth cycle is key to promoting healthy hair growth and preventing hair loss.

It is important to provide your hair with adequate nutrients to support healthy growth. Eating a balanced diet that is rich in vitamins and minerals such as biotin, iron, and vitamins C and D, can help promote healthy hair growth.

While this latest research may be useful in developing future treatments, there are lots of factors that can lead to hair loss. To get to the bottom of your hair loss or thinning, book a consultation with a dermatologist that specialises in hair loss.