Skin pigmentation: its causes and how to treat it
- August 30, 2018
Hyperpigmentation, like any other disease, is a protective mechanism gone wrong.
Skin pigmentation issues take place when melanin, our skin’s reddish-brown pigment, gets overproduced by the body. Indians have a genetic susceptibility to pigmentation; more than 80% of our country’s population has been found to have an uneven skin tone, across ages and genders.
There could be many reasons for pigmentation, with its treatment methods varying accordingly. To understand why they occur, let’s first look at how melanin works in the body.
The production of melanin
As humans, we have evolved to produce melanin, our skin’s reddish-brown pigment, to protect our skin from UV radiation.
The amount of melanin that’s naturally present in our skin – in the absence of sun exposure – is known as our ‘constitutive pigmentation’. The more melanin our body naturally produces, the darker our skin is, and vice versa.
Melanin is produced by certain cells called ‘melanocytes’, which reside in our skin (and certain other areas, like our eyes), through a process called ‘melanogenesis’.  Once made, the pigment is transferred into the surrounding cells, giving us our long-lasting skin colour.
Skin pigmentation disorders can manifest in different ways, due to a variety of reasons: when we’re exposed to the sun’s UV rays, due to hormonal changes, our genetics, medications, pregnancy, skin ageing or even when we use unsuitable skincare products. Once triggered, these issues can be exacerbated by the sun’s UV rays.
Let’s take a closer look at the various forms of pigmentation issues and why they occur.
Skin pigmentation types and causes
Melasma is characterised by brown to grayish brown spots called ‘macules’ that appear mostly on the face (on the cheeks, forehead and above the lips) and neck.
It affects 20–30% of Indian women between 40–65 years old, and is mainly seen in women, possibly because of hormonal changes that take place during the menstruation cycle, pregnancy and menopause.  That’s because oestrogen, the female sex hormone, increases the production of our skin’s melanin- although why only certain spots are affected hasn’t been understood, yet.
Our susceptibility to melasma can increase because of our genetics, medications and environmental factors. Furthermore, melanocytes are hypersensitive to UV light, and areas that have already been affected can overproduce melanin when they’re exposed to the sun, thus worsening the issue.
ii) Post-inflammatory hyperpigmentation (PIH)
In India, most people who have had a history of acne issues (70%, up to 35 years) show signs of PIH.  This makes sense, because PIH is a skin pigmentation disorder that occurs after an inflammatory response to trauma.
Pimples, sunlight, lasers, scratches, rashes, burns (and so on) create inflammation in the area, which involves a surge of blood flowing to the area (to bring in the white blood cells and other blood components that kickstart the healing process).
The increased blood flow stimulates the melanocytes, which makes them secrete more melanin and darken the area. Inflammation also brings free radicals to the area, which send melanocytes into overdrive as well.
Actinic lentigines (also called solar lentigines or lentigo senilis), are light brown to dark brown spots that are seen as even-colored or crisscrossed patches.
These mainly occur in sun-exposed areas (the bank of hands, forearms, chest and face), since lentigines are a sign of photoageing, with their frequency increasing as we grow older. In fact, their number is an indication of the amount of sun exposure a person has had over a lifetime and their corresponding risk of developing skin cancers. 
According to a large study on Indian women, lentigines affects one-third of the women of about 50 years old and half of those over 70 years old. 
iv) Periorbital hyperpigmentation
Periorbital hyperpigmentation (POH), commonly known as dark circles, is a skin pigmentation disorder surrounding the eye. It is a significant problem found especially in Asians; in an Indian study, it was found that POH was most prevalent in the age group of 16 to 25 years, and in women
There is very little scientific data available on how and why this occurs, but the reasons include genetics, inflammatory reactions that take place due to allergies, skin problems, water retention or even a shadow caused by one’s facial structure..
Vitiligo is a condition of ‘hypo’ (less) pigmentation that causes patches of light skin.
This happens when melanocytes are destroyed, purportedly because of an autoimmune disorder or a virus (like Espstein-Barr, hepatitis E & C and HIV, as examples). Globally, it appears to affect between 0.5 and 2 percent of people.
Its treatment methods
Treating skin pigmentation can involve various methods. While it’s best to consult a dermatologist to understand which works best for you, here’s a brief look at what those treatments could involve.
i) Topical creams
A dermatologist may prescribe a cream that contains hydroquinone, a compound that lights and fades the patches of skin that have been darkened, by slowing down the production of melanin in the skin and allowing those spots to gradually fade and match the rest of the skin’s tone.
Topical products may also include plant-based acids (kojic or ellagic acids), extracts (licorice, arbutin, soy), vitamins and antioxidants like vitamin A, C, and B3. It’s best to consult a dermatologist to identify the best treatment for skin pigmentation.
ii) Chemical peels
Apart from creams, you may also be advised to get chemical peel, which involves applying a chemical agent to the skin that triggers the controlled destruction of the skin’s upper layers, making them shed. This brings the newer, spot-free layers of the skin to the surface, and even kickstarts the skin’s regeneration process.
iii) Laser Treatment
There are several laser options available for the treatment of hyperpigmentation disorders, including Q-switched (QS) ruby, QS alexandrite, and fractional photothermolysis.
These directly target the melanin spots and stimulate the skin’s repair process. Since some conditions of hyperpigmentation are close to the surface of the skin and others are much deeper, your dermatologist will be able to help you choose the right laser.
Tips to reduce skin pigmentation
i) Use a sunscreen:
Sunscreens act like barriers, by diffusing and deflecting the sun’s UVA and UVB rays. Many may even protect the skin by absorbing the UV rays, which basically converts the UV light into heat, preventing them from harming the skin.
Look for ingredients like titanium dioxide and zinc oxide, and make sure your sunscreen is “broad-spectrum” or “multi-spectrum”, to make sure you’re getting protection from both UVA and UVB rays.
Consuming antioxidants helps protect the skin from the sun’s UV rays. These can be found in foods like bell peppers, dark leafy vegetables, citrus fruits (like oranges), tomatoes, peas and papayas.
Certain antioxidants like vitamins C and E are especially effective because they bind to copper. Our body needs copper in order to produce melanin; by binding to copper, antioxidants reduce its availability for melanin production, thus reducing hyperpigmentation.]
Carotenoids are also a noteworthy a group of antioxidants, found in (because they actually give the colour to) a yellow-orange-red fruits and vegetables. These deposit in the skin and protect it from UV rays. One of these, lycopene, a red pigment called lycopene also works with colourless carotenoids called phytofluene and phytoene in tomatoes, which together protect the skin from the entire UV-A and UV-B range of light.
Polyphenols are another important group of antioxidants, found in all types of plant foods, that also help with photoprotection. In fact, grape seed extract, which is rich in a polyphenol called OPCs (short for Oligomeric Proanthocyanidins), was shown to improve melasma in a small study.
Getting enough of these nutrients in our everyday diet might not always be possible, in which case consuming supplements could be helpful.