The summer has arrived in the northern hemisphere, and after the lockdown period, it will be a nice relief for most of us for sure. We understand that you can’t wait to enjoy some sun and nice warm weather, but let us first tell you what you are going to be exposed to. Sun can be a good friend of ours, especially as it stimulates the assimilation of vitamin D by our body and promotes the good functioning of our hormonal system.
However, abuse of exposure to sunlight can become harmful for your overall health, as claimed by the World Health Organisation (1): “…Exposure to the sun is known to be associated with various skin cancers, accelerated skin ageing, cataract and other eye diseases, and possibly has an adverse effect on a person’s ability to resist infectious diseases..“
This is the result of the potentially damaging ultraviolet (UV) radiation (1). But what is UV radiation exactly and why can it be harmful? As visible light can be divided into colors which we can see in a rainbow, UV is subdivided and commonly defined as UVA, UVB and UVC. All UVC (very short wavelength UV) is absorbed by the atmosphere and does not reach the earth’s surface. UVB is biologically damaging UV, but most of this is also absorbed by the atmosphere. Long-wavelength UVA is the most intense UV reaching the earth and can penetrate furthest into the tissue, but it is not as biologically damaging as UVB (1).
So, to enjoy the sun without harm to health, we compiled some advice for you:
Find the sunscreen adapted for your skin type:
We are all different. According to Thomas B. Fitzpatrick, an American dermatologist who created the well-known phototyping scale in 1975, we can all be divided into six skin types (2). Stay careful and choose your sunscreen according to your phototype! Sun protection is particularly important if you live in or plan to travel to regions such as Australia and New Zealand. There, the ozone layer (protecting the atmosphere from UVA and UVB rays) is depleted to such an extent that it leaves “holes”, causing higher UV exposures (1). Ozone holes have now also been reported over parts of Europe and North America (1);
Read labels and check the expiration date of your sunscreen:
The American Academy of Dermatology recommends everyone to use sunscreen that offers the following: Broad-spectrum protection (protects against UVA and UVB rays); SPF 30 or higher and water resistance. Dermatologists recommend using sunscreen every day when you are outside, not just during the summer. If you are using sunblock every day and in the correct amount, a bottle should not last long. It is recommended to keep a sunscreen for 3 years maximum (The FDA requires that all sunscreens retain their original strength for at least three years). If the expiration date has passed, throw away the sunscreen, as it has lost its protective power (3).
Avoid sun exposure in the hottest day hours:
The intensity of solar UV, and especially UVB, depends on the height of the sun in the sky1. This will vary depending on the season of the year, time of day and latitude in which you live. UV intensity is highest during the summer months in the 4-hour period around noon. UVB intensity varies more with the time of the day than does UVA. The rule is “when your shadow is shorter than your own height” you may receive half more of the harmful UVB during the 4 hours around noon. The latitude will influence the sun intensity too: UVB is two to three times more intense in equatorial areas than in northern Europe. (1)
Drink water and hydrate your skin and mouth:
When exposed to intense sun, we are tending to lose a lot of water through sweat. It is a natural protective measure of the body to rebalance its temperature. We tend to forget about our mouth when it comes to hydration, but for those suffering from dry mouth, summer is one of the worst seasons of the year. Usually, it is recommended for an adult younger than 60 to drink 30ml of water per kilo of weight, but this amount depends on many various factors such age, gender, physical activity and outside temperature, of course. In the case of heat, health professionals recommend to drink at least 2L of water per day and this quantity should be increased with physical activity. Learn more here about how to treat dry mouth.
Eat colourfully with fruits and veggies:
We have already discussed how our diet influences our overall well-being, and, especially in the summer, what we eat can have a big impact on our quality of life. Vitamins are usually good for us (in reasonable and adapted quantities, of course) and some studies show that some specific vitamins are specially adapted for the summertime as they support the body in hot, sunny weather. A few examples:
Since the 1930s, research has shown that vitamin C (ascorbic acid) supplementation helps the body physiologically respond to heat stress. It reduces your likelihood of developing heat-related illnesses such as heat rash and heat exhaustion. Daily vitamin C supplementation also shortens the length of time it takes your body to adjust to a new hotter environment. Vitamin E is known as a powerful antioxidant that helps skin to regenerate and maintain its healthy state.
Vitamin D is often related to skin domain. Indeed, it increases the skin’s thickness, and thicker skin means fewer wrinkles, which is why vitamin D is a popular ingredient in anti-ageing skincare remedies. Research has found that sunlight is essential for vitamin D synthesis, which in turn, is crucial for our immune system and bone generation. Vitamin A (retinol) has demonstrated an anti-ageing effect.
Treat sunburns properly:
It’s important to begin treating a sunburn as soon as possible. In addition to stopping further UV exposure, dermatologists recommend treating a sunburn with (3):
• Cool baths to reduce the heat.
• Moisturizer to help ease the discomfort caused by dryness. As soon as you get out of the bathtub, gently pat yourself dry, but leave a little water on your skin. Then apply a moisturizer to trap the water in your skin.
• Aspirin or ibuprofen. This can help reduce 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.
And do not hesitate to consult the doctor in case of a severe burn.
We really hope that you will spend an enjoyable summer without any harm to your health, and only the smile on your tanned (or not) face will remain as a holidays proof.
 INTERSUN report (https://www.who.int/docstore/peh-uv/pub/whoehg95-17.htm)
 Sharma AN, Patel BC. Laser Fitzpatrick Skin Type Recommendations. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2020.
 Thiele JJ, Ekanayake-Mudiyanselage S. Vitamin E in human skin: organ-specific physiology and considerations for its use in dermatology. Mol Aspects Med. 2007;28(5-6):646-667. doi:10.1016/j.mam.2007.06.001
 Kulda V. Metabolizmus vitaminu D [Vitamin D metabolism]. Vnitr Lek. 2012;58(5):400-404.
 Aranow C. Vitamin D and the immune system. J Investig Med. 2011;59(6):881-886. doi:10.2310/JIM.0b013e31821b8755
 Kong R, Cui Y, Fisher GJ, et al. A comparative study of the effects of retinol and retinoic acid on histological, molecular, and clinical properties of human skin. J Cosmet Dermatol. 2016;15(1):49-57. doi:10.1111/jocd.12193