Each hair has an a follicle which contains pigment cells that make melanin, this is a chemical that gives your hair its colourl. As you age these cells start to die. Without pigment, new hair strands grow and become lighter, and take various shades of gray, silver and eventually white.
Once a follicle stops making melanin, it will not make coloured stands again. But wait a minute, this is the natural course of things. There are variants :
On average, white people start to gray in their mid 30s. Asians in their late 30s. And Africans usually do not see colour changes until their mid 40s. Some people go gray 10 or more years earlier than the average person does – called premature graying. It is premature if you are gray before;
• 20 – if you are white.
• 25 – if you are Asian.
• 30 – if you are African.
What are the causes of premature white hair?
1. Genetics
According to a research published by Healthline magazine – your makeup plays a big role in when, if, you develop white hair. If you notice white hair at an early age, it is likely that your parents or grandparents also had gray or white hair at an early age.
You cannot change genetics. But if you do not like the way your gray hair looks, you can always dye or colour your hair.
2. Stress
Everyone deals with stress from time to time. The consequences of chronic stress can include, sleep problems, anxiety, change in appetite, high blood pressure. Stress can also affect your hair. A 2013 study in University of Jos found a connection between stress and depletion of stem cells in the hair follicle of mice.
So if you have noticed a rise in your number of white strands, stress might be the culprit. This theory might explain why some world leaders especially in USA, appear to age or gray faster while in office, and look younger after leaving office. A typical example is Obama.
3. Auto-immune disease
An auto-immune disease can also cause pre-mature white hair. This is when the body’s immune system attacks its own cells. In the case of alopecia and vitiligo, the immune system can attack and cause loss of pigment.
4. Thyroid disorder
Hormonal changes caused by thyroid problems such as hyperthyroidism or hypothyroidism may also be responsible for white hair. The health of your thyroid can also influence the colour of your hair. An over active or under active thyroid can cause your body to produce less melanin.
5. Vitamin B-12 deficiency
White hair at an early age can also indicate a vitamin B-12 deficiency. This vitamin plays an important role in your body. It gives you energy, plus it contributes to healthy hair growth and hair colour.
Your body needs vitamin B-12 for healthy red blood cells, which carry oxygen to cells in your body, including hair cells. A deficiency can weaken hair cells and affect melanin production.
6. Smoking
There is also a link between premature white hair and smoking. One study of 107 subjects in Oxford University England, found a connection between the onset of gray hair before the age of 30 and cigarette smoking.
It is well known that smoking cigarettes increase the risk of lung cancer and heart disease. The long term effects, however can go beyond the lungs and hearts, and affect hair. Smoking constructs blood vessels, which can reduce blood flow to hair follicles and cause hair loss. Additional toxins in cigarettes can damage parts of your body, including your hair follicles causing early white hair.
Can white hair be prevented?
• The ability to reverse or prevent white hair depends on the cause. If the cause is genetics, there isn’t anything you can do to prevent or permanently reverse the colour change.
• If you suspect a health problem consult your doctor, to see if an underlying condition is responsible for the white hair. If you treat the underlying health problem, pigmentation may return, but there are no guarantees.
• According to one study, in University of Jos, done under Japanese sponsorship, if a thyroid problem causes white hair, re-pigmentation may occur after hormone therapy treatment.
• Taking Vit B-12 shots or pills to correct a deficiency may also improve the health of hair follicles and return your natural colour.
• If white hair occurs as a result of stress or smoking, there isn’t evidence to support the return of pigmentation after quitting smoking or reducing stress. Always be medically guided.
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