Tanning, which is sometimes seen as a sign of health and aesthetically pleasing, is in fact a defense mechanism of the skin in the face of aggression. The idea that a sunscreen does not allow tanning is not only wrong, it is dangerous . Here are some things to keep in mind before you begin tanning: Frequency in sunscreen application Sunscreen should be applied before sun exposure (at home, for example) and reapplied according to perspiration and number of baths; on average, every 2 hours. It is very important to consider the applied amount (the protection index is calculated to 2 grams per square metre of skin!). Can the sun protection factor (SPF) be lowered when you are more tanned? Although increased pigmentation is a natural form of protection against solar radiation, it occurs in several ways, depending on the phototype (determined by the color of the eyes, and the skin, the greater or less ability to tan, or have sunburn). Our skin is always assaulted, and lowering the protection means a greater risk of photoaging . The harmful effects of radiation are greater with wind, and with reflection on various surfaces, such as water, sand or snow. Even on foggy days, UV radiation reaches the Earth and produces skin damage. Can we spend more time in the sun if our skin is darker? In theory it may be true, but the duration of exposure to the sun is always important, and the time for this exposure will be much more important. At noon, solar radiation reaches the earth's surface to the perpendicular, with less filtration by the ozone layer, and therefore, is more dangerous. Thus, it is advisable to avoid exposure between 11 and 14 hours in the most susceptible people. How to protect spots, scars and varicose veins from the sun? People with a tendency to develop skin spots should always apply specific sunscreens, with great protection not only against ultraviolet radiation (A and B) but also infrared radiation and even some visible radiation. This application should be daily , repeated even on cloudy days. Scars that last less than 6 months always require great protection, resorting sometimes to physical, mineral protectors (such as those for children's sunscreens). Varicose veins and other circulatory changes are particularly sensitive, not to ultraviolet radiation, but to heat, which dilates the blood vessels. Medication care: photosensitising medication and sun They is a great number the medicines (taken or applied in the skin) that can interact with the sun. Reactions may vary, allergic or toxic, with medicines that increase sensitivity to the sun, with large sunburns for small exposures. It is important to follow the medical advice regarding sun care if you are taking or administering photosensitising medication. Sun allergy and sensitive skin: what's the difference? An example of sun "allergy" can manifest itself with the appearance of pimples and a pruritus (itching) that is more or less marked, which has nothing to do with the phototype (skin color, types 1 to 6). As a rule, it gets worse over the years, both in intensity and in area. It is a relatively common situation and has preventive treatment. Sensitive skin refers to a low phototype, less equipped to defend against the sun. Examples: clear skin and eyes, freckles and poor ability to tan. The harmful effects of the sun are more likely in this population group. Does acne improve with the sun? People doing treatment for acne become more susceptible to the sun. There is a myth that acne improves in the summer. This is not true of a large number of young people who, on the contrary, are getting worse. In response to sunburn, the skin tan and thickens. This explains the increase in acne. Sun exposure of the lips and herpes The sun causes a breakdown in immunity and, therefore, herpes sufferers will have a reactivation of their viral infection. Lip protection is extremely important because the lip mucosa is very sensitive. It is a place where severe lip carcinoma can appear. Avoid sunburn The harmful effects of the sun can be immediate, provoking sunburn, which appears as redness, a burning sensation and pain, edema (swelling), vesicles and blisters. There may be fever and digestive symptoms in situations of greater severity. The most long term effects are aesthetic (the photoaging of the skin, with spots and wrinkles) and medical (skin cancer). Melanoma, with high mortality and more related to sun-scams, justifies screening and information campaigns. Two other types, much more frequent though of lesser severity than melanoma, are squamous cell and basal cell carcinomas — cancers much more related to the cumulative effect of solar radiation throughout life. Author : José Campos Lopes Meet the Dermatology team of Hospital da Luz network . The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
