We've yet to reach the dizzying levels of China, where residents wear masks to protect against the thick smog that regularly engulfs major cities, but make no mistake: pollution is a growing problem in the UK, with the European Commission warning of "persistent breaches" of air earlier pollutants this year.

And it's not just our lungs that are suffering.

"We've been studying the harmful effects of pollution for years and know it impacts many areas of our health. Given that our skin is our largest organ, it can absolutely be impacted negatively by pollution," says celebrity doctor Dr Andrew Weil.

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"Recent research shows that air pollution, especially Polycyclic Aromatic Hydrocarbons (PAH), is able to penetrate skin and generate a cascade of oxidative and inflammatory reactions that can damage the skin," explains Patricia Manissier R&D director, Caudalie.

That causes oxygen and collagen levels to drop and a slow down in cell renewal, causing skin to look "tired, older and uneven," says Fiona Brackenbury, Decleor skincare specialist.

Prevention is better than a cure

So can anything be done to tackle this invisible enemy and prevent those nasty effects from the outset?

Thankfully, yes - it's all about strengthening the skin's barrier function.

"When pollution reacts with UV rays, it destroys skin's lipid layer, a natural barrier that holds in moisture and keeps out dirt and irritants," says Dr Weil. "Effectively building up this barrier can help prevent damage triggered by environmental skin irritants."

Manissier recommends Caudalie Vineactiv 3-in-1 Moisturiser, because "it includes an anti-pollution polysaccharide veil, which acts like an invisible shield on the skin, blocking pollution particles from being absorbed by the skin."

Antioxidant-rich foods can also help boost your defences from the inside, Brackenberry notes, so include red fruits and vegetables as part of your five-a-day.

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Clean up your act

It's impossible to prevent ALL of those minuscule fragments of complexion-stressors from making it past the epidermis, so at night, it's important to sweep away as many as possible.

"Oily skin is a magnet for dirt and pollution because pollution is oil soluble; it allows particulate matter to seep into skin and clog pores," explains Lizz Starr, executive director of global product development at Origins, who believes micellar water is the best product to get the job done.

"It contains tiny micelle molecules, which act like magnets to grab onto and trap unwanted oil, pollution and dirt. Impurities are then easily lifted away and wiped off with a cotton pad."

Overnight success

"The antioxidant system is weakened after each attack of skin aggressors and becomes less and less effective, leading to premature ageing," Dr Weil warns - which is why as a final nightly step, a serum will get to work on repairing damage caused by pollution.

"Night-time's the best time to repair the damage, because not only is the skin most receptive, but its cell renewal is at its peak whilst you sleep," agrees Brackenberry.

"Overnight skin repairing is crucial, as free-radical damage affects so many parts of the skin. Essential fatty acids are needed to repair the hydrolipidic film, as pollution and free radicals damage skin, and it can take up to eight hours to repair itself.

"Pollution also causes dehydration, so hyaluronic acid is key at night-time to replace lost moisture in the skin."

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