Skin Cancer

Everything You Need To Know About Sun Cream

Everything you need to know about sun cream

A Q&A with a consultant dermatologist




Qualifications: BSc(Hons), MBBCh, FRCP
GMC: 3241101

Dr Hudson-Peacock is the Director and Clinical Lead at the Canterbury Skin and Laser Clinic, also known as Stratum Clinics Canterbury. He was the Senior Consultant Dermatologist in the East Kent Hospitals University NHS Foundation Trust, a post he held from January 1996 until January 2014, when he left to focus his energy to bring a new medical treatment to the NHS. He is a general dermatologist with specialist interest in skin and laser surgery. Here he answers your top questions on sun cream.


Everyone needs sun cream and you should be wearing it every time your skin is exposed to sun light, no matter your skin type. Sun cream helps prevent skin cancer by protecting your skin from the sun’s harmful ultraviolet (UV) rays.

Anyone can get skin cancer, regardless of age, race or gender and skin cancer is the most common form of cancer in the UK, with around 150,000 people being diagnosed with non melanoma skin cancer each year in the UK. The appearance of a new mole, or any changes to an existing mole anywhere on the body, could be an indication of a melanoma


There is a lot of sun cream on offer which can make it very confusing to know what you should be buying and how each brand varies from each other. There are a few things we suggest you look out for when buying sun cream to ensure you are getting the required protection:

  • Buy a broad-spectrum protection, this is one that protects against both UVA and UVB rays
  • Always go for an SPF 30 or higher protection
  • Make sure the sun cream is water resistant, this is especially important if you will be in our around water but is also important if you will be doing outside sport where you expect to sweat

To put this into simple terms, when you are in the shop looking at different sun cream, the label should have:

  • a sun protection factor (SPF) of at least 30 to protect against UVB
  • at least 4-star UVA protection
  • If you have a history of sun damage and/or skin cancer, it is recommended to choose a sunscreen with an SPF50 and 5* UVA protection


Most people apply less than half of the amount of sunscreen required to provide the level of protection indicated on the packaging. People miss areas too, like the back and sides of the neck, temples, ears and behind the ears.

There is a vast range of different product types available, so it is not possible to give a set amount that you should apply that is the same for all products. Individual manufacturers can provide further details specific to the application of their particular sunscreens.

For simplicity, when using lotions, as the bare minimum you should apply at least six full teaspoons (approximately 36 grams) to cover the body of an average adult.

Over half a teaspoon should be applied to the face, neck and backs of ears and over half a teaspoon to each arm. A full teaspoon should be applied to the back, one to the chest and one to each leg. Applying less sun cream will reduce the protection to a higher degree than is proportionate – for example, only applying half the required amount can actually reduce the protection by as much as two-thirds.

When it comes to sun cream, more is better and it is important to reapply every two hours, immediately after swimming, perspiring and towel drying or if it has rubbed off.

Apply sun cream 15 to 30 minutes before going out in the sun to allow it to dry, and then again shortly after heading outdoors to cover any missed patches and to make sure you’re wearing a sufficient layer.

‘Water resistance’ is tested by the ability of a sunscreen to retain its sun protection properties following two 20 minute intervals (40 minutes total) of moderate activity in water. Up to 85 percent of a product can be removed by towel drying, so you should reapply after swimming, sweating, or any other vigorous or abrasive activity.

If the sun’s rays are reflected, the radiation can increase greatly: snow up to 85% increase, sand up to 17% increase, water up to 5% increase.


This one is another very simple message: every day if you go outside. The sun emits harmful UV rays year-round. Even on cloudy days, up to 80 percent of the sun’s harmful UV rays can penetrate your skin. It is especially important to apply SPF from March to September, when the UV rays are at a higher concentration and you are less likely to have your skin covered by clothing.


Yes, but we recommend using a sunscreen with an SPF of at least 30, which blocks about 96% of the sun’s UVB rays. Higher-number SPFs block slightly more of the sun’s UVB rays, but no sunscreen can block 100% of the sun’s UVB rays.

But remember: high-number SPFs last the same amount of time as low-number SPFs. A high-number SPF does not allow you to spend additional time outdoors without reapplication so no matter what factor you choose, you should be re-applying every two hours.


If your skin gets burned by the sun, it’s important to begin treating a sunburn as soon as possible and get out of the sun. We recommend treating a sunburn with:

  • Cool baths to reduce the heat
  • Moisturiser to help ease the discomfort caused by dryness. As soon as you get out of the bathtub, gently pat yourself dry, leaving a little water on your skin. Then apply a moisturiser to trap the water on your skin.
  • Hydrocortisone cream that you can buy without a prescription can help ease discomfort
  • Aspirin or ibuprofen. This can help reduce the swelling, redness, and discomfort
  • Drinking extra water. A sunburn draws fluid to the skin surface and away from the rest of the body. Drinking extra water prevents dehydration

If your skin blisters, you have a second-degree sunburn. In this case, we recommend that you:

  • Allow the blisters to heal untouched. Blisters form to help your skin heal and protect you from infection
  • If the blisters cover a large area, such as the entire back, or you have chills, a headache or a fever, seek immediate medical care
  • With any sunburn, you should avoid the sun while your skin heals. Be sure to cover the sunburn every time you head outdoors


The challenge with sun cream sprays is that it is difficult to know if you have used enough sunscreen to give you the correct coverage as sometimes some of the spray will miss your body or the spray will be translucent. When using spray sunscreen, make sure to spray an adequate amount and rub it in to ensure even coverage.

To avoid inhaling spray sunscreen, never spray it around or near the face or mouth. Spray the sunscreen into your hands and then apply it to these areas can help you avoid inhalation while also ensuring adequate coverage.


Using sun cream may decrease your skin’s production of vitamin D, although a recent study has suggested that even using a high SPF does not significantly reduce your Vitamin D levels. However, in the UK, as a nation, we get less UV exposure due to our climate, so having additional Vitamin D may be worth considering, especially if you limit your UV exposure. If you are worried that you are not getting enough vitamin D, you should discuss your options with your doctor. Many people can get the vitamin D they need from foods and/or vitamin supplements. This approach gives you the vitamin D you need without increasing your risk for skin cancer.


We recommend that you wear sun cream every day that you go outside, even during winter months so a bottle shouldn’t last too long.

However, if you do find a bottle that you have not used for some time, most sun creams retain their original strength for three years. Some bottles will include an expiration date or an amount of months from opening the contents will be good for. If this time has passed, you should not use the product as it will not be as effective.  Keep an eye our for visible signs that the sunscreen may no longer be good. Any obvious changes in the colour or consistency of the product mean it’s time to purchase a new bottle.


If your baby is under 6 months, you should avoid exposing them to the sun’s rays and sunscreen should be avoided if possible for babies younger than 6 months.

In children older than 6 months, the best way to protect infants from the sun is to keep them in the shade. They should be dressed in long sleeves, trousers, a wide-brimmed hat and sunglasses. Make sure they do not get overheated, are not exposed to strong rays of sunlight and that they drink plenty of fluids.

Parents of infants and toddlers 6 months and older may apply a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher to their children’s exposed skin that is not covered by protective clothing. Sunscreens that use the ingredients zinc oxide or titanium dioxide, or sunscreens made specially for infants or toddlers may cause less irritation to their sensitive skin. Make sure the sun cream is applied regularly and to all areas including the ears and back of the neck.


There are many sunscreens to choose from. I recommend 4 different companies products to look at: these are Altruist (top seller on Amazon and British), Sunsense (great Australian brand), Heliocare (really good Spanish brand with a good tinted one that many of the ladies like) and SkinCeuticals (an American brand). There are many others as well. The important thing is to find a product you like, as you will be more inclined to use it, and for it to be fit for purpose (water resistance, tint, cream, spray etc): as individuals we are fickle about what we like to use, but the skin just needs a SPF30 or more and * rating of 4 or 5, ultimately which product you use is up to you as long as these specific features are met.

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