by Dr Divya Sharma
We often wonder what exactly is the reason for all hair issues. Well the answer is more like a jigsaw puzzle. Hair fall is multifactorial and perhaps is caused by various reasons that we will discuss in this new article.
Hair is an engineering marvel of nature
Hair is perhaps one of the few appendages in our body which possess a unique ability to regrow throughout life due to stem cells located in the bed of each hair follicle. That germ which leads to sprouting of hair is known as Dermal papilla. It is surrounded by blood vessels which are the highway connecting nutrient supply to the hair. It is anchored by a small muscle and is surrounded by our fat cells, hormonal receptors. In short, hair is an engineering marvel of nature. One can make out the very reasons why Hair is so resonant of our internal surroundings and is closely impacted by them.
How are hair fall and hair loss different?
The difference between hair fall and hair loss is that the former is temporary shedding which may be self-limiting and the latter is perhaps permanent ageing of the follicle.
Hair cycle simplified
We all know that hair has three stages of growth. The growth phase also known as anagen generally lasts on an average of 2 to 3 years. The majority of our hair is in this phase. This is followed by Catagen lasting for one month and then the hair rests in follicles known as telogen phase. On an average , 20 to 30 % of hair is in the resting phase. This is followed by the exit of old hair and entry into another growth phase.
What are the factors which can impact the hair cycle?
Hair growth cycle is a very dynamic process and requires a lot of nutritional support and is sensitive to slightest changes inside the body. Nutritional deficiencies like Vitamin B12 , Vitamin D and iron deficiency can compromise the growth phase and lead to shifting of the hair to telogen phase in a higher proportion. This is known as telogen effluvium and is responsible for the excessive shedding of hair in clumps or hair fall. Any illness, surgery or stress can trigger telogen effluvium. If it continues to happen for many months to years, it leads to reduction of hair volume and commonly people refer to it as reduction in ponytail size or visible spaces in the temple areas for women.
Hormonal changes, especially increased activity of dihydrotestosterone (DHT) or reduced activity of aromatase enzyme in women can lead to progressive miniaturisation of hair follicles known as Androgenetic alopecia. It leads to receding hairline and bald patches. Many factors like scalp microinflammation and loss of anchorage of hair follicles can lead to miniaturisation.
Why DHT leads to miniaturisation largely lies unanswered but there is a lot of evidence incriminating obesity, dyslipidemia , lack of sleep and disruption of circadian rhythm responsible for the process of balding.
Diet and everyday lifestyle is perhaps the only amenable tool for hair health. It has also been seen as a predictor of cardiovascular health.
The counterpart of metabolic syndrome in women known as PCOS or polycystic ovarian syndrome also reduces the growth signals required for initiation of hair growth. Increased insulin levels, abnormal hormonal profiles discourage hair health.
It is high time to put away the myths like hair oil and shampoos making a major impact on hair growth.
We will discuss the practical tips and tricks to treat both conditions in the next issue.
Dr Divya Sharma is a renowned dermatologist and trichologist based out of Bengaluru. She is on the scientific committee of various national regional dermatology congresses and is often invited as faculty to Indian Academy of Dermatologists, Venerologists and leprologists (IADVL), Association of cutaneous surgeons of India (ACSICON) national conferences. A member of IADVL special interest group (SIG) -Aesthetics. She runs her own practice Dr Divya’s Skin and Hair solutions at Bengaluru