Martin Lewis issues 'PAO' warning to all holidaymakers

Martin Lewis has shared a little known tip that could protect tourists' health this summer - and in years to come.

Speaking on his Martin Lewis Podcast, the financial whizz asked how many of us know if the sunscreen bottles we have in the back of our cupboards are still in date.

Sun cream products applied to the skin are designed to protect us from the sun's harmful ultraviolet (UV) rays, both UVA and UVB - but they have a shelf life.

With a bottle in hand, the broadcaster told his audience there's a very easy way of working out whether you should pack the sun protection you have in your case, or throw it in the bin.

During the podcast, he said: 'Just a quick tip on sunscreen. When you get your sunscreen, turn the bottle around because on the back you'll see a POA number.'

POA stands for 'period after opening' and is usually 12 or 24 months, he explained. It's also often found on makeup products too, and usually appears as 9M, 12M, 18M or 24M.

Lewis said that a simple label could help prevent sunburn, or worse, a future skin cancer diagnosis.

He said: '[When you open the bottle] Put a little note of the date, write that onto the sunscreen and you'll know if you try to use it in a year's time whether it's still valid or not.'

Last year, a US skin cancer expert revealed the four key body parts that are prone to skin cancer - and where people often miss applying sunscreen.

Dr Neera Nathan, a Harvard-trained skin cancer surgeon, shared a TikTok with over 680,000 views, saying she removes cancers from the backs of hands, ears, scalp and neck.

Since these areas are often exposed directly to sunlight they're particularly dangerous places to overlook.

'Most people apply sunscreen to their face but don't realize these, and these are often in direct sunlight,' Dr Nathan told Newsweek.

Dr David Kim, a New York City based dermatologist who was trained at Stanford, agreed, saying the number one place people forget to apply sunscreen is on the ears - followed closely by the scalp and hands.

He said while completing his medical degree, he regularly found skin cancers on the ears of outdoor athletes who practiced without sunscreen.

Skin cancer can occur on any part of the body, even spots not exposed to the sun.

Frequent, direct exposure to the sun's ultraviolet rays, which damage cells, increases your likelihood of developing a cancer-causing mutation steeply.

Over 80 percent of skin cancer are caused by sun exposure, according to Worldwide Cancer Research.

There are three main kinds of skin cancer - basal cell carcinoma, squamous cell carcinoma and melanoma.

Each ranges in severity and fatality, but many can be treated successfully through surgery if they're caught early enough.

Common symptoms of skin cancer include an area of discolored skin, an itching or bleeding spot, a pink lump with a hard surface and a sore that won't go away, according to Cleveland Clinic.

Another way to be on the lookout for skin cancer is to monitor your moles and freckles for the 'ABCDE's of melanoma.

This includes looking out for asymmetrical moles, moles with poorly defined borders, moles with odd coloring, moles that have a large diameter and that are evolving in shape or size.

The best way to defend yourself against this condition is to wear sunscreen and protective clothing when you go out in the sun, especially during midday, when the sun is at its peak, Dr Nathan said.

A spray sunscreen should be effective particularly for the scalp, able to get around the hair follicles, she said, adding: 'I recommend a broad-spectrum (UVA/UVB) SPF 30 or higher that is water-resistant. Sunscreen should be reapplied every two hours'.