People need to trim their hair and nails every once in a while because they keep growing continuously. However, some individuals are blessed with faster growth rates, leading to more frequent grooming sessions. So, why does this happen?
According to Michelle Moscova, an associate professor of anatomy at the University of New South Wales in Australia, on average, hair grows about 1 centimeter per month, while nails can grow over 3 millimeters.
If left unattended, hair and nails can grow to significant lengths. Slovakian woman Aliia Nasyrova holds the record for the world’s longest hair, measuring 257.33 centimeters, recognized by the Guinness World Records. Meanwhile, American woman Diana Armstrong set a world record with her nails measuring a whopping 1,306.58 centimeters.
However, most people trim their hair and nails regularly, though some individuals experience faster growth rates due to various factors.
Moscova explains that both hair and nails are composed of keratin. They grow from matrix cells beneath the skin through different cell division patterns.
Unlike nails that continuously grow, hair follows a cycle divided into four stages: (1) Anagen phase – a rapid growth phase lasting between 2 to 8 years, (2) Catagen phase – a transitional phase lasting about 2 weeks where growth slows, (3) Telogen phase – a resting phase lasting 2 to 3 months where hair stops growing, and (4) Exogen phase – shedding of hair from the follicle to be replaced by new hair from the same follicle, restarting the growth process.
Each follicle goes through this cycle 10 to 30 times in its lifetime.
Although we shed 100 to 150 hairs daily, the average person has about 100,000 hairs on their head, making the natural shedding process hardly noticeable.
Genetics play a significant role in hair and nail growth rates. While growth speeds vary between individuals, family members often exhibit similar growth rates.
Nail growth is also influenced by genetics, with siblings, especially identical twins, often displaying similar growth rates.
Several other factors can influence hair and nail growth, including age, hormones, and nutrition.
With age, metabolism and cell division slow down, resulting in slower growth rates for the elderly.
Hormonal changes can also impact growth rates. For instance, pregnancy typically accelerates hair and nail growth, while menopause and high levels of cortisol (stress hormone) can slow down growth.
Furthermore, nutrition affects the strength and growth rate of hair and nails. While primarily composed of keratin, both hair and nails also contain water, fats, and various minerals that require replenishing as they grow.
This underscores the importance of a balanced diet, rich in essential nutrients, for maintaining healthy hair and nails.
Inadequate nutrition may disrupt the growth cycle or weaken the structure of hair and nails. Deficiencies in iron and zinc, for example, are associated with hair loss and brittle nails.
Perhaps this explains why thick hair and strong, well-kept nails have long been associated with good health and higher social status.