The 'most effective' protection to avoid sunburn (and it isn't suncream)

The government is warning that the NHS will be under even more pressure this weekend as temperatures soar, so looking after yourself in the sunshine is crucial.

Read more: Amber heat health alert issued for England But how much do you know about the science behind sunburn… and how to prevent it? What is sunburn? While we all know what sunburned skin looks like - red and sore - it might not be so clear what is happening underneath the skin. "Essentially, it's inflammation," said Dr Rachel Abbott, a consultant dermatologist who specialises in skin cancer for the Cardiff and Vale University health board.

"It's triggered by ultraviolet radiation, primarily UVB but also by UVA." Ultraviolet radiation is carcinogenic and when it is allowed to penetrate the skin, it triggers an inflammatory reaction, said Dr Abbott. Histamines - chemicals produced by the body's immune system - and prostaglandins - compounds that help the body deal with injuries and illness - are released as your body begins reacting to the damage.

Although the inflamed, red, itchy skin will fade, those carcinogens will do permanent damage to your DNA, according to Dr Abbott. "The redness and pain can be managed symptomatically, but that DNA damage is permanent," she said.

"We've all got DNA repair mechanisms in our bodies. But this is why we're seeing such a massive increase in skin cancer, because [as we get older], the battle between the DNA damage and the skin cells becomes more than the immune system can cope with." Since the early 1990s, the number of skin cancer cases in Britain has more than doubled and last year, the number of cases was predicted to hit an all-time high of 20,800, according to Cancer Research UK.

The cancer charity partially attributed the rise in cases to older groups of people knowing "less about the dangers of tanning in their youth.