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The sun : you can get too much of a good thing!
This health card has been drawn up in collaboration with
Professor Michel de la Brassine, Department of Dermatology, ULg-CHU
Enjoy the sun, but with moderation
There would not be any life or light on earth without the sun ! The sun is indispensable to both our physical and mental health: not only does it enable us to build up our reserves of vitamin D (which protects our bones, preserves our muscle tone, etc.) but it also helps treat certain skin disorders (such as psoriasis). And while we tend to see only the aesthetic benefits of sunbathing, it also offers a form of natural protection against sunburn: pigment-making cells (melanocytes) are activated, producing more melanine, our natural sun filter. The corneous layer of the epidermis thickens and is thus able to reflect some of the sun's rays. Our skin becomes less fragile, as long as exposure is progressive and an appropriate sunscreen is used. Finally, starting off a day under sunny skies usually gives us a boost and puts us in a good mood. It is no wonder that luminotherapy treatments are recommended for depression.
(The luminette was created for this purpose by a spin-off company of the University of Liège. Press release)
However, the sun can also put us at risk if we get too much of it (through succumbing to the fashion of intensive tanning or neglecting to take basic precautions). This reduces our "solar capital" and may endanger our health.
Protecting your "solar capital"
Individuals are not equal before the sun; people with light skin are obviously more sensitive to the sun than olive-complexioned Mediterraneans or dark-skinned Africans, even though these latter two groups are also susceptible to sunburn.
Safe exposure time depends on what type of skin you have; however, these data are only intended to provide an approximate idea, as other factors, such as the sun's intensity, time of day, etc. must also be taken into account.
Repeated exposure leads to potentially long-term cumulative (and irreversible) effects and accelerates skin aging and wrinkle formation in particular; further, we would be remiss if we did not mention the carcinogenic effects of the sun light. These are ample reasons to take all the precautions necessary to preserve our "solar capital". Although the amount of capital an individual is endowed with varies from one person to the next and is not measurable, it is not renewable and corresponds to the amount of radiation an individual can be exposed to before developing a pre-malignant or malignant lesion. More exposed areas (the face, neck, the ears, the calves, balding areas) are obviously at greater risk, all the more so as we often neglect to protect them properly (hat, sunscreen, etc.). The answer is not to hide from the sun, but to derive maximum benefit from its precious rays while protecting oneself.
UV stories
UV rays are invisible and represent part of the sun's energy; they are classified according to their wavelengths: The flux of particles (primarily photons) emitted by the sun move toward the earth at a speed of 300 000 kms/sec, reaching it at different wavelengths expressed in nanometers.
Some UV rays are filtered out by the atmosphere, but only those less than 270 nanometers (UVC's). UVA's (between 310 and 400 nanometers) and UVB's (between 270 and 310) are subject to lesser filtration. This is especially true if the atmosphere and ozone layers are thin, and the degree of UV radiation accordingly very high. This is also the case at higher altitudes (where more protection is needed) and when the sun is at its zenith (when it is advisable to stay out of the sun between noon and 4:00 p.m.). The consequences for the skin differ according to the type of UV ray.
It is possible to establish "reasonable" exposure times according to skin type, but these should be taken as rough guidelines only! More information
Children and the sun
The sun should remain a friend and a source of well-being for children as well. They need to be afforded special protection: they should remain inside at midday, wear t-shirts and hats and remain in the shade at all other times. High SPF sunscreen lotion should be applied and re-applied on all visible parts of the body, especially when children go swimming or play beside the water, where reflection is greatest.
Because sand also reflects the sun, it is possible to get a sunburn even under an umbrella. Infants under the age of one should stay in the shade at all times, as their skin is too fragile to be exposed.
Helping mother nature: Sun-tanning lamps, sun-tanning beds, self-tanning lotions
Sun-tanning lamps and sun-tanning beds
A great many people use them, either to get a tan or to give their moral a boost at times of the year when sunlight is scarce; some of us use them intensively, convinced they are harmless. Unfortunately, this is not the case! In fact, intense artificial UVA stimulation, when combined with the effects of natural sunlight, causes the skin to age prematurely. Eventually, the suntan ceases to be uniform, and unsightly, white spots may appear on the skin as it accumulates the traces of all types of exposure, thereby increasing the risk of our solar capital being used up. Sun-tanning beds must thus be used only occasionally and for brief periods of time. They may be useful in specific cases (allergies to the sun, sensitive skin, etc.) where having a slight pigmentation serves as protection against future exposure. However, generally speaking, it is better to avoid them and under no circumstances should they be used by children and teenagers.
Nevertheless, if you still decide to use them, make sure that you take basic precautions such as reducing the number and length of the sessions and wearing protective glasses (UVs are not good for your eyes either) and opt for beds whose lamps are maintained on a regular basis. Finally, remember to limit the amount of time you spend in the sun. It is better for your skin!
N.B.: The above does not concern the medically supervised use of sun-tanning beds.
What about self-tanning lotions ?
Many cosmetic companies market them, promising us a nice healthy glow even during the grey winter months. The results obtained are a substantial improvement over those of the past: the end colour is no longer an artificial-looking orange, the lotions are easier to apply ("progressive" formulas guarantee a uniform tan), and the skin remains well hydrated. Moreover, self-tanning lotions are totally harmless as they only tint the corneous layer of the epidermis and oxidize it. They provide an interesting alternative, then, for all those who love that suntanned glow! Note that selftans do not protect against sunburn. Self-tanning and sunscreen lotions are two entirely different products!
Sun-tanning pills are also used to pigment the skin (they contain carotene) but sometimes make it look very orangy (especially on the palms of the hands) and, like the lotions, do not protect your skin.
Sunscreen lotions: the basics
| Basic requirements: | Choose a high sun protection factor of at least 20 and preferably 50. | |
Remember to apply sunscreen lotion anytime you are exposed to the sun, not only when sunbathing. | ||
| A waterproof cream? Preferably: even if you do not go in the water, a waterproof lotion will remain effective even when you perspire | ||
| Is a single thick coat enough ? No! Re-apply the lotion frequently, especially if you have sweated a lot or have gone swimming (even if the label says that it is waterproof), or used a towel to dry yourself. It is recommended that you apply sunscreen lotion at least once every two hours. Beware of reflection, especially on snow, water or sand. You can get a sunburn even if you remain under an umbrella because of the sun reflecting on the sand. | ||
| Can you get a sun tan if you put on sunscreen lotion? Sunscreen lotions are especially effective at filtering out UVB's; UVA's, responsible for tanning, are only partially filtered out. | ||
| Should expiry dates be strictly adhered to ? Yes, and storage conditions as well! For lotions to remain effective from one year to the next, they have to be stored under specific conditions, ones that are difficult to emulate in a typical household. Chemical filters in sunscreen lotions deteriorate quickly when exposed to light and heat and thus lose their protective capacity. It is better to buy them in smaller amounts and keep them out of direct sunlight, preferably in the fridge. | ||
| Can you get a sunburn even when it is not sunny ? Indeed. You are exposed to UV radiations as soon as you set foot outside. Even when you are fully dressed, you still have to protect certain areas, particularly your nose, ears, arms and bald spots. Moreover, weather conditions may modify your perception of heat and the sun's rays: e.g. you may not realize that your skin is actually burning because it is windy. | ||
You got a sunburn or had a sunstroke all the same ?
- Seek shade immediately to avoid photoaddition (a cumulative and toxic effect of radiation) and stay out of the sun for at least 24 hours.
- Take a lukewarm shower to cool down and to rehydrate your skin.
- Apply an emollient to the burn. Use a slightly greasy cream or a good moisturizing lotion.
- Apply a corticosteroid-based ointment if your burn is serious (you might need to go to your doctor to get a prescription)
- In the case of an extensive burn, you may need to go to the hospital.
- See your doctor if you run a fever, vomit, or do not feel well.
- Sunburns are generally accompanied by dehydration. It is thus recommended that you drink water to which sugar and mineral salts have been added or fruit juices.
Sunglasses
Sunglasses are an integral part of the typical vacationer's must take list. They come in all shapes and colour to meet our each and every whim. We are most often concerned with how they look on us, but their prime function is to protect us.
UV's are indeed not very good for the eyes: UVB's penetrate the crystalline through the cornea, and UVA's may reach the retina. Lesions may be very severe (sometimes acute photo-conjunctivitis, inflamed cornea, etc.). UV's and especially the sun may induce the onset of cataract.
Even when your eyes are closed, you are not protected against UV's as eyelids do not entirely block them. Good sunglasses are indispensabe: your lenses should be large enough and the frame offer lateral protection. Tinted lenses protect you from sun glare but not from UV's.
The European UV protection factor ranges from 0 to 4. Factor 3 is the best choice. Factor 4 is indispensable if you are in a mountainous region (snow reflection) but is not suitable for driving. Choose the frames that you like most, be sure to request high quality lenses and... stay protected. NB. The CE label is a guarantee that the frames comply with safety norms, but does not apply to the lenses.
Certain situations may entail specific risks
Some products have photosensitizing properties, i.e. they make your skin overly sensitive to the sun, which causes you to burn very easily. The association of the sun and certain drugs, cosmetic products, and even certain plants or foods may provoke sunburn or allergic reactions. Your family doctor can give you a list of precautions and advise you as to how to prevent such problems from occuring. There are several categories of photosensitizers:
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Let's talk about the other risks!
Let's face it: the sun may also be responsible for the development of skin cancers, many of which may be cured if diagnosed at an early stage. Some symptoms may arouse our suspicion and lead us to visit a specialist for diagnosis and adequate treatment. But as is always the case, prevention is the best treatment.
The sun is a precious gift, let's keep it that way!