As well as being a source of energy and helping our bones, the sun's rays help our immune system respond to micro-organisms that attack it.
The structure of our body, what keeps us upright and protects our organs, the skeletal system, depends on the vitamin D. Helps our body absorb calcium and maintain bone mineralisation.. This prevents us, with age, from suffering osteoporosis and the fractures associated with this disease.
But where does vitamin D come from? From the sun. Our own body synthesises this vitamin when the skin is exposed to the sun. It only takes 15 minutes, three days a week to maintain the correct levels of this vitamin. There are also foods that provide it - eggs, cheese, mushrooms... - but contact with the sun's rays is a good source of this "protector".
This is not the only beneficial effect of the sun. The sun's rays are a engine for our immune system. Sunlight provides energy to T-cells, which are essential for human immunity. These white cells are involved in the cellular immune response and go wherever there is an attack on the body.
A study by Geogetown University in 2016 revealed how low levels of blue light, which is found in the sun's rays, causes T-cells to move faster by better synthesising hydrogen peroxide. This compound is released by white blood cells when they detect an infection. Its function is to kill bacteria and call upon the cells of the immune system to respond to the infection. With the action of the sun, T-lymphocytes can reach their target faster.
But how does the sun reach T lymphocytes? Nur skin - the dermis - contains a large number of our body's T-cells and light, by penetrating this layer, can help the cells move throughout the body.
Invisible sunlight damage, photoimmunosuppression and how to avoid it
Just as it has undeniable beneficial effects, the sun's rays can also affect our immune system. The skin is our body's first defence barrier and its cells can be damaged by solar radiation. The immune system is weakened, leading to a saturation of its defence mechanisms.
This damage affects the DNA of cells. In this sense, every hour of exposure to the sun counts towards increasing the risk of skin infections, photodermatosis, chronic inflammatory diseases and even neoplastic lesions.
Because of the consequences of sunlight on our inune system, we talk about photoimmunosuppression.
On the contrary, what we have to apply in summer are photoprotection measures. Sunscreens are a good barrier that penetrates the pores of the skin - we have an average of 5 million pores all over the body - and converts the sun's rays they absorb into heat and releases them from the body. You could say they make the UV rays "bounce back".
Sun creams can be composed of chemical filters and mineral filters. The former are regulated to prevent excessive amounts from entering our bloodstream. The latter are considered safe when the particles are larger than 30 nanometres, thus preventing them from penetrating the skin. For this reason, sun creams with mineral filters are the most recommended for protect our overall health.
SUN EXPOSURE. RISKS AND TREATMENT. Read the article
