How do sunscreens work and why are they needed?
Ultraviolet radiation, which is part of the sunlight reaching us, not only colors the skin in the color of vacation or hard work in the sun. It also harms the skin, sometimes irreparable: it destroys DNA and causes premature aging, dehydration of the skin and cancer.
What happens when the sun shines on the skin
Sunlight (like any other) is a stream of quanta of electromagnetic radiation, photons. A photon is a discord to a photon: low-energy ones do no harm to biological tissues, but photons of higher energy (and shorter wavelengths) can destroy DNA and are harmful to all living things.
Our luminary emits electromagnetic waves in a wide range: everything flies to the Earth, from harmless long-wave photons to destructive short-wave ones - ultraviolet and X-rays. Substituting the body under the “uncleaned” sunlight is like drinking a cocktail of water, vodka and engine oil: some of its components are more harmful than others, others are completely harmless, but all together is poison.
Fortunately for us, in the path of sunlight is a natural filter - the ozone layer, which reflects the highest energy waves - X-rays and hard ultraviolet. Without the ozone layer, solar radiation would kill almost everything living on Earth. Our metaphorical cocktail is cleaned of engine oil. But what reaches the planet’s surface can still be harmful. Especially in large quantities.
What happens when the sun shines on the skin
Sunlight (like any other) is a stream of quanta of electromagnetic radiation, photons. A photon is a discord to a photon: low-energy ones do no harm to biological tissues, but photons of higher energy (and shorter wavelengths) can destroy DNA and are harmful to all living things.
Our luminary emits electromagnetic waves in a wide range: everything flies to the Earth, from harmless long-wave photons to destructive short-wave ones - ultraviolet and X-rays. Substituting the body under the “uncleaned” sunlight is like drinking a cocktail of water, vodka and engine oil: some of its components are more harmful than others, others are completely harmless, but all together is poison.
Fortunately for us, in the path of sunlight is a natural filter - the ozone layer, which reflects the highest energy waves - X-rays and hard ultraviolet. Without the ozone layer, solar radiation would kill almost everything living on Earth. Our metaphorical cocktail is cleaned of engine oil. But what reaches the planet’s surface can still be harmful. Especially in large quantities.
From what the ozone filter passes, the most harmful thing for us is ultraviolet: soft (UVA, with a wavelength of 320 to 400 nm) and hard (UVB, 320-400 nm).
Our tissues contain molecules that are tuned to work with just such photons - they translate them into an excited state, and the molecules enter into chemical reactions that do not occur in the absence of ultraviolet radiation. As a result of some of these reactions, the production of melanin, the pigment that makes the skin tanned, starts in the cells.
And UVA penetrates deep into the skin and destroys collagen protein - the one to which we owe skin elasticity, and UVB - burns and causes redness and soreness.
But the main threat is that both UVA and UVB can cause DNA mutations. If they cannot be neutralized, a benign tumor develops around the cell with mutated DNA.
Soft ultraviolet light also triggers cascades of reactions in the skin that help fight free radicals - which is good, but its hard counterpart - and, in some cases, soft on its own - activates oxidants in skin cells, and the cells cannot withstand the general stress that causes all to the same consequences: collagen loss and DNA breakdown. The constant repetitive exposure to sunlight during life can lead to skin cancer. It doesn’t matter if you are white, like Michael Jackson, or black, like Michael Jackson: ultraviolet is carcinogenic for all skin types and shades.
How to protect yourself?
You can, of course, avoid the sun all your life (especially in the summer) and hide behind umbrellas and scarves, but this is not convenient for everyone. If you still have to go out under the scorching rays, you can apply sunscreen to the skin. Any of them contains molecules specially selected for their ability to reflect ultraviolet light. Even a thin film of such molecules can reverse the whole effect of ultraviolet radiation on itself (if the molecules in it act like chemical filters) or simply reflect harmful radiation (if physical filters are like small mirrors).
The most popular of these filters are zinc oxide (chemical filter) and avobenzene, a physical filter: in order to reflect both UVA and UVB, a combination of them is required. It is important to remember that, unlike a regular cream, the amount of which is regulated by the skin’s ability to absorb, a sunscreen should be applied until a layer of a substance is formed that is sufficient to protect the skin from ultraviolet radiation; Some studies by American health officials show that people use less cream than they need.
Our tissues contain molecules that are tuned to work with just such photons - they translate them into an excited state, and the molecules enter into chemical reactions that do not occur in the absence of ultraviolet radiation. As a result of some of these reactions, the production of melanin, the pigment that makes the skin tanned, starts in the cells.
And UVA penetrates deep into the skin and destroys collagen protein - the one to which we owe skin elasticity, and UVB - burns and causes redness and soreness.
But the main threat is that both UVA and UVB can cause DNA mutations. If they cannot be neutralized, a benign tumor develops around the cell with mutated DNA.
Soft ultraviolet light also triggers cascades of reactions in the skin that help fight free radicals - which is good, but its hard counterpart - and, in some cases, soft on its own - activates oxidants in skin cells, and the cells cannot withstand the general stress that causes all to the same consequences: collagen loss and DNA breakdown. The constant repetitive exposure to sunlight during life can lead to skin cancer. It doesn’t matter if you are white, like Michael Jackson, or black, like Michael Jackson: ultraviolet is carcinogenic for all skin types and shades.
How to protect yourself?
You can, of course, avoid the sun all your life (especially in the summer) and hide behind umbrellas and scarves, but this is not convenient for everyone. If you still have to go out under the scorching rays, you can apply sunscreen to the skin. Any of them contains molecules specially selected for their ability to reflect ultraviolet light. Even a thin film of such molecules can reverse the whole effect of ultraviolet radiation on itself (if the molecules in it act like chemical filters) or simply reflect harmful radiation (if physical filters are like small mirrors).
The most popular of these filters are zinc oxide (chemical filter) and avobenzene, a physical filter: in order to reflect both UVA and UVB, a combination of them is required. It is important to remember that, unlike a regular cream, the amount of which is regulated by the skin’s ability to absorb, a sunscreen should be applied until a layer of a substance is formed that is sufficient to protect the skin from ultraviolet radiation; Some studies by American health officials show that people use less cream than they need.