All of a sudden, it seems that everywhere we turn there are suncream ads and the shops are filled with offers on summer essentials. So should we be making the most of the bargains to restock the bathroom cabinet — or can we ignore the marketing ploys and dig out supplies that have been lurking at the back for years? Alice Smellie asked industry experts to find out if it’s really vital to buy new supplies for summer . . . Scroll down for video . Out-of-date sun lotions may separate and not spread evenly, say experts, meaning you may not be completely covered with vital UV filters, even if the active ingredients in the sun cream remain stable . SUNSCREEN . There can be few of us who haven’t dug out half-full bottles of SPF30 from the previous year or, indeed, many years past, and wondered whether it’s still OK to slather on. But a recent survey revealed that almost three-quarters of UK holidaymakers are at risk of UV exposure because they use out-of-date sun cream. Many experts recommend that we wear sunscreen every day all year round for anti-ageing purposes. Certainly now the weather is heating up, damaging UVA and UVB rays will be stronger. So, can we use old suncreams? ‘Sun cream contains UV filters which fall into two main categories: synthetic or organic filters, which absorb UV light; and mineral or inorganic filters, such as titanium dioxide, which mainly reflect UV light. Frequently, both types are used in combination,’ says Dr Chris Flower of the CTPA (Cosmetic, Toiletry & Perfumery Association). The issue is that out-of-date lotions may separate and not spread evenly, meaning you may not be completely covered with those vital UV filters, even if the active ingredients remain stable. When it comes to sun cream, experts advise playing it safe and restocking your supllies to ensure skin is properly protected from damaging damaging UVA and UVB rays . Out-of-date lotions are also more likely to cause skin irritations. Ingredient specialist and product developer Tammy Hollis says: ‘Look at how we treat our suncreams — carrying them from sandy beach to sunny bar and air-conditioned hotels. This gives plenty of opportunity for bacteria to breed.’ So experts recommend you don’t use a sun cream beyond the recommended period after opening. This is represented on the packaging with a picture of an open jar and a number of months (usually 12) in most popular brands of sunscreen. Meanwhile, Dr Flower advocates: ‘Chances are it will probably be OK if it’s just over a year old, although older bottles should definitely be binned.’ VERDICT: Play it safe. Restock. AFTER-SUN . In an ideal world none of us would get sunburn, but occasionally we underestimate the heat of the sun. While it can’t reverse the damaging effects of the sun, after-sun contains soothing ingredients such as water, aloe vera and silicones, which evaporate quickly from the skin and cool it down. Dr Flower says: ‘The main effect is to cool and reduce the effect of over-heating and to help avoid skin peeling.’ While after-suns may seem innocuous products, people forget they are applied to vulnerable, damaged skin. For this reason it’s vital that you adhere to the recommendations regarding when you should discard lotions . While after-suns may seem innocuous products, people forget they are applied to vulnerable, damaged skin. For this reason, it’s vital that you adhere to the recommendations regarding when you should discard lotions. ‘Damaged skin may be more prone to developing irritations, allergies or infections anyway,’ says Dr Flower. ‘So the older the after-sun, the more likely it is to contain bacteria. If a pathogenic organism — a disease causing bacteria — was applied to damaged skin, then it’s possible you might develop an infection of the skin.’ VERDICT: Restock. MOSQUITO REPELLENT . No one wants to be the person on holiday who is stung from top to toe, and in tropical countries where malaria is a risk then an effective repellent is vital. But can you keep using the same spray year after year? ‘Insect repellents work in two different ways,’ says Howard Carter, CEO of Incognito mosquito spray and a mosquito bite prevention expert. ‘Many brands use Deet as their active ingredient. This is a neurotoxin which interferes with the mosquito’s nervous system. They become confused and are prevented from biting.’ When it comes to bottles of insect repellent, experts say you're probably ok to use the same bottle for a couple of years, but keep a close eye on the use-by date, especially if travelling to far-flung countries . Howard says that if any bottle of Deet is open it must be replaced after two years because the active ingredient may stop working as effectively. He adds: ‘Be aware that it can corrode through plastic bottles and cause damage to surrounding items.’ He says that those containing natural ingredients such as citronella or bergamot, may only last a year – this is because oil may lose certain components of its scent and potency, though others, including Incognito, can last for up to two years. VERDICT: You’re probably ok for a couple of years, but keep a close eye on the use-by date, especially if travelling to far-flung countries. FAKE TAN . The sun is shining but your legs are as white as the winter snow. Who hasn’t shaken up that bottle of fake tan mousse that’s been lurking at the back of a cupboard for an indeterminate number of years and looked despairingly at the green tinged product that emerges? ‘The DHA which creates the brown colour is a derivative of fermented sugar beet,’ says ingredient expert Tammy Hollis. ‘When it goes on the skin it’s not stimulating melanin production (which is what happens when you’re in the sun), but reacts with proteins on the top layer of skin known as the epidermis to turn brown. Fake tan usually lasts 12 months once opened. The active ingredient DHA is usually in water-based solutions without many preservatives, say experts.  Once it is past its use-by date it oxidises and goes green . ‘This active ingredient is usually in water-based solutions without many preservatives. Once it is past its use-by date it oxidises and goes green. The smell may become slightly metallic or stronger.’ Fake tan usually lasts 12 months once open. VERDICT: If it looks ok, you can probably go ahead. BITE CREAM . This is a medicine cupboard staple which is probably used little more than twice a year, so it can take a long time to finish a tube. ‘Anti-histamine, hydrocortisone bite creams and crotamiton itch creams are the three common forms of treatment for stings and bites,’ says pharmacist Sultan Dajani, spokesperson for the Royal Pharmaceutical Society. ‘Once open, these creams will go off more quickly if they aren’t stored properly — they must be in a cool, dark place otherwise bacteria may be introduced or they simply won’t work as well. If you store it properly it will last up to the expiry date, which may be as much as two years.’ VERDICT: Restock as soon as it is out of date, or if it is runnier than normal or smells funny. HAIR COLOUR PROTECTION SPRAY . UV exposure is extremely damaging for coloured hair. Scientists have found large amounts of cysteic acid (usually found in badly permed hair) in the ends of lank locks which had had a great deal of sun exposure. This causes hair to lose strength and snap. Protection in strong sunlight is highly recommended. Most hair protecting sprays recommend you discard after 12 months. Consultant trichologist Iain Sallis. ‘If you store it in a cool dry cupboard with no light they may last longer than 12 months but once the heat and light of sunshine get in, as is likely on holiday, the ingredients will start to degrade more quickly.’ The result is that hair will no longer be protected. VERDICT: If stored away from the light, you don’t need to restock.
Will out-of-date sun lotion protect your skin from sun damage? Can you keep using last summer's bite cream? Alice Smellie finds out which summer supplies we need to restock .