Thin-skinned. Thick-skinned. Skin deep. The English language is full of idioms that relate to our largest organ, our skin. You’re thin-skinned if you’re sensitive; thick-skinned if you’re impervious to criticism; and beauty, apparently, goes no deeper than the epidermis. The average adult has almost two square metres (21 sq ft) of skin, and it accounts for about 15 per cent of our body weight. The thickest skin is found on the soles of our feet, the thinnest on our eyelids. Beauty obviously isn’t just skin deep – it must go way deeper, to the essence of who we are. But our skin’s appearance can make us feel more, or less, confident – and more or less attractive. Our skin is the barometer for so much – heat, anxiety, cold, infection, illness. At least five receptor types in the skin respond to pain or touch. Even our thought processes affect our skin: a fight-or-flight response prompts adrenaline production which causes our heart rate to rise and blood vessels to dilate, although curiously only the ones in our face. Then we blush, exposing our emotions. Charles Darwin said that blushing was the most peculiar and most human of responses. It can be embarrassing but it can also make us more attractive, even though it is a transient reaction to a fleeting situation. Sometimes, though, the skin reacts more violently to stressors. And those reactions last longer. Hong Kong dermatologist Dr John Yu says those stressors may be emotional and come from within us. They may also be environmental, such as pollutants and UV rays which can lead to free radicals – unstable molecules that can damage cells, causing illness and ageing. Skin 101: ageing, acne, sweating, cancer – and best ways to protect it Hong Kong skincare specialist Florence Fatialofa explains the effects of stress and anxiety on our skin: “Skin goes through a process of inflammation when we are stressed.” That is part of a domino effect that “triggers the cells in our body to react to an increase in cortisol”. Cortisol produced in response to stress messes up our skin in myriad ways: it interferes with the natural production of hyaluronic acid and collagen – ingredients found in skincare products because both are valuable for their youthful, skin-plumping properties. And chronic inflammation, says Fatialofa, “thins the skin, accelerating premature ageing”. She calls this “inflamm-ageing”. Cortisol also causes the skin’s oil-producing sebaceous glands to go into overdrive. Oily skins get oilier, Fatialofa says, leading to breakouts and congestion. So thanks to the havoc-wreaking cortisol, your skin may be ageing, while you may also suffer from the acne you thought you’d left behind in your teens. Acne left her ‘defeated’; skin positivity movement helped her smile again Constant inflammation can lead to rosacea flare-ups – unsightly and uneven skin redness; a weakened skin barrier with a reduced ability to keep moisture in and allergens and pollutants out; and melasma – dark spots and broken capillaries that look like webs across the nose and cheeks. Sarah, a teacher who has been working in Hong Kong for five years and wants to remain anonymous, knows the effects of stress on skin. She began to get spots, under-the-skin congestion (deep, painful eruptions beneath the skin that never come to a proper head) and rosacea. Her skin was shiny, her cheeks warm and flushed – not in an attractive way. Because her job requires face-to-face contact, Sarah grew self-conscious and “cancelled plans because of it”. That’s not uncommon, says Fatialofa. “The way our skin looks has a direct link to how we feel about ourselves.” Eczema sufferer on her all-natural solution to beating her condition Sarah sought Fatialofa’s advice after she had already experimented with some products. “I’d stripped my skin by over-exfoliating, which made it sensitive. I also wasn’t using a moisturiser because I didn’t want to clog my pores,” Sarah says. That is a common mistake, says Fatialofa. When our skin is not looking good, that leads to further stress and panic buying of the wrong products – and finally making an appointment to see a skin professional – often expecting to need to do something radical and invasive. “But a big skin response doesn’t warrant a big reaction … keeping things simple with a couple of key consistent products is sometimes all it needs to regain balance.” Fatialofa recommends avoiding balm or foam cleansers during a stressed skin episode. A micellar water – made up of “micelles”, or tiny balls of cleansing oil molecules suspended in soft water – is a good option. She recommends using a moisturiser containing barrier-repairing ceramides, a non-scrub exfoliator such as one with an enzyme, or gentle acid pads, and avoiding essential oils and astringents until balance is regained. After two months of treatment which included steam-and-clean facials and lymphatic drainage massage to clear away toxins below the skin surface, Sarah says her skin is calmer. “I try to manage my triggers (excessive heat, hot yoga and coffee) but at least now when my skin plays up I know what to do,” she says: to fight inflammation she uses a portable fan to cool her skin when it’s hot outside, and at home, gives her face an ice massage. Like what you read? Follow SCMP Lifestyle on Facebook , Twitter and Instagram . You can also sign up for our eNewsletter here .