The reaction that causes your skin to brown is linked to ageing and disease. Photo / Getty
It's touted as the healthy way to acheive a golden glow, but experts have revealed how fake tan could be damaging your skin.
One in three women are said to use tanning products, and as formulas improve we're seeing less streaks and orange palms and more natural looking, bronzed skin.
But experts aren't convinced that the ingredients in fake tan, or the methods of application, are good for us. Yes, they're safer than lying out in the sun but they're not entirely risk free.
How fake tan works
Fake tans work by reacting with your skin's outer layer, which is mainly made up of dead skin cells. It's called the Maillard reaction and causes what's known as oxidative stress: creating compounds that turn skin cells brown and cause the same type of damage as pollution or sunbathing.
The concern is around the active ingredient in this reaction: Dihydroxyacetone, or DHA. It's been used as a skin colourant since the 1920s and is derived from sugar cane. It's also what gives fake tan that biscuit smell.
"We don't know the long term effects," Dr Stefanie Williams, dermatologist and founder of London's Eudelo skin clinic told the Daily Mail. "They may be insignificant, but oxidation is linked to ageing and disease".
So while you may be doing your best to stay out of the sun to avoid not just cancer but the effects of ageing, your fake tan alternative could also be the cause of lines and wrinkles.
While DHA was approved by the US Food and Drug Administration in the seventies, it's safety rating excludes inhalation, which can occur with spray tan use.
According to Dr Williams, "If DHA is inhaled into the body, or enters membranes in the eyes and mouth, it can reach cells in the respiratory tract and lungs."
In 2012, toxicologist and lung specialist Dr Rey Panettieri warned that regular inhalation could worsen asthma or potentially lead to cancer.
While there's no conclusive evidence that spray tans are dangerous or safe, Dr Williams advises against regular visits.
What about lotions, gels, mousses and creams?
Cosmetic scientist Ian Taylor told the Daily Mail "As a cancer-causing agent, there are no issues with DHA applied externally."
The concern is around other ingredients that can be added in the production process which may cause problems.
Cheaper processes where synthetic raw materials such as solvents are used could lead to accidental contamination.
Some products also contain "penetration enhancers", such as ethanol alcohol which is used to help speed up or deepen the tanning process.
But Taylor says they can disrupt the skin's barrier by "increasing moisture loss and making skin more vulnerable to pollutants".