With the arrival of summer, instead of hopeless clouds we finally get enough of the sun - and enter into a very different relationship with it: someone regularly hides from it, and someone is struggling to get a tan. Many of those who do not belong to any of the camps, but feel that everything is not so simple, have long wanted to understand once and for all which of the two extremes is more common sense. So that this summer the sun was only a joy, we offer an educational program: we understand how solar radiation affects the appearance and health of the skin, what are the vicissitudes of a tanning bed and what to look for when choosing solar protection products.
Why is it considered
what is good for sunbathing
Many sunbathers sunbathe for more than just their golden skin. In society, the opinion that sunbathing is extremely useful and, moreover, necessary, in particular for the production of vitamin D in the skin, is thoroughly entrenched. This vitamin has a lot of merits, for example, it is believed that it works "against" depression, namely, it participates in regulation of tyrosine hydroxylase - an enzyme necessary for the production of dopamine (the so-called hormone of happiness), as well as adrenaline and norepinephrine.
Accordingly, many scientists have long associated seasonal affective disorder (also known as seasonal depression) with a lack of vitamin D. And two years ago, researchers in Singapore discovered the effect of vitamin D levels in a woman's body on the treatment of candidiasis, or thrush, an infection caused by a yeast-like fungus. One of the important functions of vitamin D is to stimulate the production of the antimicrobial peptide cathelicidin, which helps us manage inflammation.
Vital vitamin D is actually synthesized in human skin by exposure to ultraviolet rays, but you don't have to spend hours in the sun or buy a tanning bed for an annual subscription. If you are a resident of a region where there are no noticeable interruptions in the sun, rest easy: your skin receives the necessary dose of ultraviolet rays during simple walks on sunny days. For most people with fair skin, spending 10-15 minutes in the sun three times a week is enough to maintain adequate vitamin D production.
In northern latitudes, this is not always possible even in summer, not to mention the autumn-winter season. So people living in these regions, and especially those whose skin is dark or dark, will benefit from slightly longer contact with the sun's rays on those days when they still break through the clouds - of course, provided that protective equipment is used from the sun (more on them later). Anyway, too long exposure to the sun negatively affects all skin types.
How different types of solar radiation work
The sun produces as many as three types of radiation: the visible spectrum - what we call sunlight, and ultraviolet (UV) and infrared (IR). Infrared radiation is mainly caused by a thermal effect - simply put, it keeps us warm. In turn, the ultraviolet is responsible for the photochemical effect: it is from it that we get the tan, so it is worthwhile to understand the specifics of UV radiation in more detail.
UV radiation (in the international version UV - ultraviolet) is divided into three spectra depending on the wavelength, and each spectrum has its own characteristics of the effect on the human body. Spectrum C has a wavelength of 100 to 280 nm. These rays practically do not reach the surface of the Earth, being absorbed by the ozone layer of the atmosphere - and good, because this is the most active range: when they penetrate the skin, the rays of the C spectrum can cause a destructive effect on the cells of the body.
We often associate golden skin tones with good health, which is called glowing skin in the beauty industry
Spectrum B, with a wavelength of 280–320 nm, accounts for about 20% of all UV radiation reaching the Earth's surface. It is UVB rays (UVB) that we owe redness on the skin after a carefree rest under the scorching sun. Spectrum B has a mutagenic effect - it actively affects the cellular DNA and causes various violations of its structure - from the rupture of pairs of nitrogenous bases with the subsequent formation of "wrong" cross-links to DNA cross-linking with a protein, the synthesis of which is activated under the influence of UV, failures in cell division and denaturation DNA. During cell division, such changes are "inherited" by daughter cells, remain with us and can lead to systemic mutations at the genome level.
Spectrum A, with a wavelength of 320–400 nm, accounts for almost 80% of all ultraviolet radiation that reaches human skin. Due to their long wavelength, the rays of the spectrum A (UFA) have about 1000 times less energy than the spectrum B, therefore they hardly cause sunburn. They contribute to a much lesser extent to the production of biologically active substances that can affect DNA, but these rays penetrate deeper than UVB, and the substances they produce (for example, reactive oxygen species) remain in the skin for much longer.
What is tanning
If nanometers and nucleotides don't impress you, then the chemical background of the visible changes that occur to the skin due to sunburn will surely make you think. Skin is our body's protective shell, and when exposed to ultraviolet radiation, it throws all its strength into creating an effective barrier. In this sense, much depends on the upper layer of the epidermis - the stratum corneum. Living cells keratinocytes, which are produced in the lower layers of the epidermis, are eventually pushed to the surface, harden and die off, and the keratin in the dead scales protects us from heat and cold.
The epidermis also contains special cells called melanocytes, which produce the dark pigment melanin, which protects the skin from burning to a certain extent. The very bronze skin tone, for which desperate vacationers lie under the scorching sun for days on end, is the reaction of melanin skin in response to its damage by UV rays. It becomes keratinized, drier and darker. Terrible associations can be traced in the language itself: the meaning of the word "tan" in English (tan) is rooted in the processes of tanning animal skins for the production of various products.
Is it true that tanning
Does it “age” the skin?
The natural "tanning" of our skin under the influence of the sun does not go away without consequences. We often associate golden skin tones with good health, which is called glowing skin in the beauty industry. At the same time, we forget that tanning - acquired both naturally and in a tanning bed - aggravates the effect of aging. The lion's share of the signs that are considered an integral part of skin aging are actually triggered by unprotected sun exposure.
For premature aging of the skin, or the so-called photoaging, it is mainly the ultraviolet radiation of the A spectrum that is responsible. Over time, UV rays damage the elastin fibers, and when they disintegrate, the skin begins to stretch and sag, becomes more prone to edema and microtrauma, and heals more slowly. Sunlight also affects freckles and the so-called age-related pigmentation: it can not only darken age spots, but also provoke the production of melanin, as a result of which new spots are formed - even if they were previously removed with a cream or laser.
While we are young and careless, the influence of the sun on the condition of the skin may be imperceptible, but over the years all the consequences are literally evident (and not only). In addition, the older we get, the lower the skin's ability to regenerate and the weaker its protection against the harmful effects of ultraviolet radiation.
Can sunbathing trigger cancer?
So, the cumulative effect of UV radiation provokes the uncontrolled growth of atypical skin cells. This can lead to the development of tumors - both benign and malignant (cancerous) - basal cell carcinoma, squamous cell carcinoma, or melanoma.
Basal cell carcinoma is the most common form of skin cancer. The name comes from the basal cells that underlie the outermost layer of the skin. Basal-type cancer cells grow slowly and usually do not spread to other tissues in the body. Exposure to ultraviolet radiation, especially in childhood, is recognized as the main cause of their occurrence. The fact is that errors in the structure of cellular DNA accumulated since childhood disrupt and deplete the sun-protection function of the skin, increasing the risk of skin cancer in adulthood. Both basal cell carcinoma and squamous cell carcinoma, which develops from squamous cells, in most cases occurs in areas of the skin most often exposed to sunlight - mainly on the head, neck and arms. In addition to genetic predisposition, fair skin is a risk factor.
Excessive exposure to ultraviolet rays and, accordingly, increased production of melanin can lead to the formation of moles - accumulations of melanocytes. Most moles appear during puberty and may disappear during life. But under the influence of external factors, including ultraviolet radiation, a pigmented mole (nevus) can develop into melanoma - one of the most dangerous malignant tumors.
Of course, hereditary predisposition, mechanical effect on a mole and much more play a big role, but we note that people with light skin, prone to sunburn, who are in the open sun or in a solarium for a long time, do not care about funds protection. According to statistics, 8 out of 10 cases of melanoma in the UK could be prevented if patients controlled their exposure to the sun, avoided sunburn and did not abuse tanning beds.
Doctors do not recommend prophylactic removal of nevi, since in most cases the birthmark does not degenerate into melanoma. Nevertheless, if nature has rewarded you with an abundance of moles, you should independently monitor the condition of your skin and undergo regular examination by a dermatologist.
Which is safer:
sun or solarium
Not everyone is ready to wait for summer to get tanned - solarium sessions have gathered an army of fans. From unskilled beauticians, you can often hear that a few minutes in a tanning salon is equivalent to several hours spent on the beach. Let's immediately dispel the sheer myth about the safety of this procedure in comparison with the effect of direct sunlight: when sunbathing in a solarium, the human skin receives the same radiation as when sunbathing in the open sun, which means that there is no fundamental difference between a 10-minute session in a solarium and 10 -minute tanning under the scorching sun.
There is also an opinion that tanning in a solarium is an effective method of treating acne and many other skin diseases. In fact, this is not the case. Under the influence of ultraviolet rays, keratinization of skin cells occurs, dead keratinocytes clog the outflow of the sebaceous glands of the skin and can only intensify acne. The effectiveness of ultraviolet rays of the spectrum A and B has been proven only in cases of treating some forms of psoriasis, while phototherapy does not exclude the risk of cancerous tumors.
The World Health Organization recommends against tanning
in a solarium for cosmetic purposes
Europe is full of old people who are tanned to a deep brown hue. The reason is not a banal love of sunbathing: many residents of Western Europe visit a solarium, hoping to strengthen their bones: fans of "artificial" tanning are in an eternal pursuit of the notorious vitamin D, which ensures the absorption of calcium and phosphorus from food in the small intestine. As a rule, such enthusiastic hypochondriacs are engaged in the self-appointment of a tanning bed, but sometimes the procedure is prescribed by doctors, which makes them seriously doubt their qualifications.
We repeat: the skin will cope with the synthesis of vitamin D even without regular frying in the sun or in a solarium. Such an aggressive effect of UV rays has an adverse effect on the skin, contributing to its early aging, the appearance of microcracks and wrinkles. According to the latest research and guidelines from the World Health Organization, tanning beds should not be used for cosmetic purposes.
Before a tanning salon session, clients are told that the radiation intensity can be adjusted according to their skin type. There are pitfalls here too. The fact is that people with very light skin, which quickly burns in the sun, have an increased risk of developing cancer, and the absence of burns on the skin as a result of tanning in a tanning bed can give the false impression that the skin is much more resistant to radiation than on in fact, the risk of developing complications is very small.
Why do we tolerate the sun differently
Each of us is protected to varying degrees from the harmful effects of sunlight. People with dark skin have stronger protection, and red or blond people with pale skin and blue eyes are more susceptible to sun attack due to the lower concentration of photoreceptive (light-receiving) melanin in the skin.
It is believed that the skin comes in different phototypes and this characterizes its sensitivity to the effects of ultraviolet radiation. Some modern physicians, when determining the phototype, use the Fitzpatrick classification of 1975, in which the American dermatologist identified six main types of skin - from Celtic to African American. If representatives of the first (Celtic) and second (Nordic) phototypes quickly burn out in the sun, then the owners of the fifth (Middle Eastern or Indonesian) and sixth (African American) skin types - dark or dark, - according to Fitzpatrick, never burn under the influence of sunlight and practically do not need to use sunscreen.
Such racial determination is somewhat outdated and does not always correspond to the real state of affairs. Firstly, it is quite obvious that everyone burns in the sun - ask any carrier of the "Indonesian" phototype: it's just a matter of time and the degree of carelessness of the sunbather. Secondly, in representatives of mixed races, the skin behaves in a specific way, taking "all the best at once" from a variety of phototypes, and, as you know, there can be an infinite number of ethnic combinations. So to promise mulatto patients one hundred percent sun resistance and not prescribe the proper remedy is an indicator of medical negligence. It does not hurt to be guided by a conventional phototype when choosing SPF products, but we note that they are recommended to be used by absolutely everyone, regardless of the so-called phototype, at least to prevent skin photoaging.
What is SPF and how to choose a remedy
So, we found out that sun protection is necessary for everyone, albeit to varying degrees. Gloss has long trumpeted that you shouldn't go out without applying SPF to exposed skin, but when it comes to choosing a specific product, it's hard not to get confused. What do all these numbers mean, what consistency to choose, how to find a cream that does not cover the face and body with a white layer, is it worth buying decorative cosmetics with a sun protection factor - there are a lot of questions.
SPF (sun protection factor) is the main marker to look for when choosing a UV protection product. SPF is calculated using a formula in laboratories, based on the assumption that the product will be used in an amount of 2 mg per 1 cm² of skin surface, which means that for reliable protection, it must be applied in a sufficiently dense layer. Many people think that the SPF value allows you to calculate the time for safe exposure to the sun, but this is not entirely true. The term SPF indicates how much UV radiation you can get without the risk of burns with a given sunscreen. The SPF index does not characterize the time, but the increase in the skin's resistance to burns. SPF 50 means you can withstand 50 times more UV exposure than without it. Note that dermatologists recommend renewing the protection every two hours, not neglecting it even on cloudy days, and applying a new layer of the product after contact with water or sand.
Dermatologists recommend renewing your defenses every two hours and not neglecting
her even on cloudy days
When choosing a sunscreen by SPF, one should take into account not only the so-called skin phototype (as we have already found out, this is a rather conditional guideline), but also the degree of its thinness, elasticity and sensitivity. Your location is also important: the closer you are to the equator, the higher the solar activity and, therefore, the higher the risk of sunburn. We recommend choosing creams, sprays and decorative cosmetics with broad spectrum protection - they block the emission of spectra A and B. By protecting yourself from the rays of spectrum A, you sacrifice sunburn to a certain extent, but ensure skin health. The optimal ratio is considered to be the proportion of UVB to UVA filters in the amount of 3: 1.
Sunscreens are made on the basis of two types of ingredients: they are either absorbent organic filters, or screens - inorganic particulate matter that reflects UV rays (usually titanium dioxide, zinc oxide, or a combination of both). Filters penetrate the skin and transform solar energy into thermal energy. Unlike filters, screens remain on the surface of the skin.
Some filters, such as oxybenzone and retinol palmitate, are considered hazardous and oncogenic and should be avoided. By the way, the Environmental Working Group, an American non-profit research organization in the field of toxic substances and corporate responsibility, does not recognize any active ingredient in sunscreens as 100% safe, but still strongly recommends using them and even offers its top relatively safe products.
If your skin is sensitive, prone to acne, hyperpigmentation or any other peculiarities, when choosing sun protection, do not neglect the consultation of a dermatologist: the doctor will help you choose a non-comedogenic, hypoallergenic product or a special product designed to more effectively prevent the formation of age spots. In any case, don't be lazy to use basic sun protection - it's as natural a health concern as washing your hands regularly. We'll tell you more about how to choose sunscreen for different purposes and budgets.
Photos: Weekday, Oséa