Why does my skin look dull and tired, and what can I do?

Skin that looks dull and tired all the time usually comes from several everyday things at once: sun you get without noticing, too little sunscreen or not reapplying it, dry skin, short sleep, smoking and alcohol. So looking after it works on two sides. On the outside, protect from the sun properly and keep skin from drying out. On the inside, sleep enough, stop smoking, drink less and eat enough fruit and vegetables. If a mark or your skin colour changes quickly, see a dermatologist.

Why does my skin look dull and tired all the time?

There is rarely a single cause. It is usually a mix of habits and surroundings your skin meets every day. Go through the list below and see which ones fit you.

Daily sun you do not notice

In Thailand the sun is strong for most of the year. The WHO says that at a UV index of 3 or above there is an increased risk of skin damage and protection is recommended, and UV is strongest around midday.

Many people think they are not out in the sun, but the American Academy of Dermatology (AAD) points out that:

• up to 80% of the sun's harmful UV rays can get through clouds, so overcast days still count
• UVA rays pass through window glass, while UVB rays are blocked by it, so sitting by a window or driving every day still exposes you to UVA

Short bursts of sun, such as walking to the bus stop, the morning market or a desk by the window, add up and are easy to overlook.

Dry skin that looks rough and flat

Dry skin looks rough and flaky and reflects less light. The AAD lists common causes of dry skin: long hot showers, deodorant soaps and harsh cleaning products, dry air and smoking. Skin also makes less oil as we get older. Here, sitting in air conditioning all day can dry the air around you too.

Washing or exfoliating too hard

Scrubbing your face hard or exfoliating often to make skin look fresh can backfire. The AAD warns that over-exfoliating can leave skin red and irritated, and that scrubbing while washing your face irritates the skin. Red, dry, irritated skin looks uneven and tired.

Short sleep

Lack of sleep really does show on your face. A study in the journal Sleep in 2013 photographed 10 people after normal sleep and again after 31 hours awake following a night of only 5 hours' sleep. Forty observers rated the photos. The sleep-deprived faces were seen as having paler skin, darker circles under the eyes, redder and more swollen eyes, more hanging eyelids and more droopy corners of the mouth. In short, they looked more tired.

Smoking and alcohol

The AAD says smoking gives skin a dull, sallow complexion and causes wrinkles, and that alcohol dehydrates the skin. If you smoke, or drink often during a run of parties, you may notice your skin looking duller.

I wear sunscreen every day but my skin still looks dull. Why?

The usual answers are too little sunscreen, no reapplying, or relying on sunscreen alone without other sun protection. Sunscreen then protects less than you think.

Using too little

The AAD advises at least 1 teaspoon for the face, and says most adults need about 1 ounce, roughly a shot glass full, to cover the body. The UK's NHS says adults should aim for around 6 to 8 teaspoons to cover the whole body. Many people squeeze out a small dot and spread it thin, which is far less.

Remember your neck, ears and the backs of your hands, which catch the sun when you drive or commute.

Putting it on only once in the morning

Sunscreen does not stay on all day. The AAD advises reapplying every 2 hours when outdoors, and straight after swimming or sweating. The NHS explains that the sun can dry it off your skin, and that you should reapply after being in water even if it is water resistant. In Thailand's hot, humid weather you sweat easily, so this matters.

Going straight out after applying

The AAD says skin takes about 15 minutes to absorb sunscreen before it protects you. The NHS suggests applying it 30 minutes before going out and again just before you go.

SPF and UVA protection

SPF mainly tells you about UVB protection. The AAD says SPF 30 blocks 97% of UVB rays, higher numbers block only slightly more, and no sunscreen blocks 100%. It recommends SPF 30 or higher with broad-spectrum (UVA and UVB) protection that is water resistant. The NHS recommends at least SPF 30 and high UVA protection. Sunscreens sold in Thailand often show their UVA protection level as a PA rating.

Relying on sunscreen alone

The NHS says plainly not to rely on sunscreen alone: wear suitable clothing and stay in the shade when the sun is at its hottest. The WHO recommends layers of protection at a UV index of 3 or above (shade, clothing, a hat, sunglasses and sunscreen) and, at 8 or above, avoiding being outside during midday hours. An umbrella, a wide-brimmed hat and walking on the shady side of the street often do more than a higher SPF number.

I wear sunscreen every day but my skin still looks dull. How do I look after it from the inside?

Looking after your skin from the inside means adjusting your daily habits. What medical sources agree on is to sleep enough, stop smoking, drink less alcohol, eat a variety of fruit and vegetables, and keep moving.

Sleep 7 hours or more

The US CDC recommends that adults aged 18 to 60 sleep 7 hours or more, and suggests these habits:

• go to bed and get up at the same time every day
• turn off electronic devices at least 30 minutes before bed
• avoid large meals and alcohol before bed
• avoid caffeine in the afternoon or evening

If work thoughts keep you awake, see Can't sleep because your mind won't stop thinking?

Stop smoking and drink less

The AAD advises stopping smoking if you smoke, and drinking less alcohol because it dehydrates the skin. When parties pile up, skip drinking at some of them or alternate with water. If you want to stop smoking, a doctor or pharmacist can help.

Eat a variety of fresh fruit and vegetables

The AAD recommends a healthy, well-balanced diet with plenty of fresh fruit and vegetables. With Thai meals this is easy to build in:

• order extra vegetables with a one-plate dish, or add a clear vegetable soup, stir-fried greens or blanched vegetables with chilli dip to the meal
• have fresh seasonal fruit after meals instead of a sweet dessert, and vary the kind
• choose whole fresh fruit over juices with added sugar

Drink enough water and keep moving

Sip water through the day, especially on hot days, in air conditioning all day, or when you sweat a lot. The AAD also suggests exercising most days of the week. If you sit at a desk all day, get up and walk for short breaks.

How do I look after the outside of my skin so it does not dry out and look dull?

Besides sunscreen, gentle washing and moisturising are the everyday basics.

Wash gently

The AAD suggests:

• wash your face twice a day, morning and night, and after heavy sweating
• use lukewarm, not hot, water
• choose a gentle, non-abrasive cleanser that does not contain alcohol
• use your fingertips, do not scrub, and pat dry with a soft towel

Moisturise while skin is still damp

The AAD suggests keeping showers and baths to 5 to 10 minutes in warm water, applying moisturiser while your skin is still damp after a shower or washing your hands, and reapplying several times a day when skin feels dry. A cream or ointment moisturises better than a lotion. If air conditioning leaves your skin tight, a humidifier can help.

Exfoliate only as much as you need

If you exfoliate, the AAD suggests you:

• choose a method that suits your skin; dry or sensitive skin may need only a washcloth and a mild chemical exfoliator
• do more aggressive methods less often
• apply gently in small circles for about 30 seconds, then moisturise straight away
• never exfoliate skin with open cuts or wounds, or sunburned skin

Also stop using products that sting or burn, because irritated skin looks red and uneven.

When should I see a dermatologist about dull skin?

Skin that looks dull from short sleep or everyday sun is common. But see a doctor or dermatologist if you notice any of these:

• a new dark mark or patch, or one that grows quickly
• your skin colour changes quickly for no clear reason, for example getting darker or paler all over
• a mole that changes size, shape or colour
• a mole or mark that is painful, itchy, inflamed, bleeding or crusty
• a new or unusual mark that has stayed for several weeks without going away
• very dry skin that itches all the time and does not get better with self-care
• dull skin together with unusual tiredness, unplanned weight loss, or other symptoms

If you use a prescribed medicine or skin product, or think a medicine you take regularly is changing your skin, do not stop or switch it on your own. Talk to a doctor or pharmacist.