Can You Tan in the Shade?

When the skin is exposed to the sun's UV rays, it reacts by stimulating melanin production of the melanocytes. The melanin then migrates to the surface of the epidermis to color and protect it: this is tanning. Can you tan without sun exposure? Sitting in the shade doesn't completely protect us from UV rays.

The elements in our environment, such as sand, snow, or the surface of water, can reflect sunlight onto our skin. Our skin then comes into contact with harmful UV rays, even when we're under a tree or parasol. So, it's perfectly possible to tan in the shade. However, the extent of the tan obtained depends on the type of shade and the environment's ability to reflect UV rays. The UV reflection index of some surfaces is shown in the table below.

Note: It's good to know that cloudy weather also creates shade that does not protect the skin. In fact, only large, dark clouds are capable of blocking all UV rays. A medium-altitude cloud layer will only be able to block 30-60% of the sun's rays. Moreover, if the clouds are white and scattered, UV rays will be reflected, increasing radiation by 10%.

Since the sun's UV rays can reach us when we're in the shade, it's important to protect our skin, also under these conditions. UV rays can cause irreversible damage. They generate free radicals in our bodies that can alter cell membranes, but also induce changes in the genetic code, leading to mutations and even the proliferation of cancerous cells.

Finally, free radicals can also denature certain proteins essential to the skin. Penetrating right down to the dermis, UVA rays stimulate cutaneous aging and promote the appearance of wrinkles, fine lines and pigmentation spots. UVB rays, on the other hand, cause skin issues, such as sunburn and more serious conditions such as skin cancer.

So, it's essential to protect yourself from UV rays by applying a broad-spectrum sun cream daily to exposed areas of the face and body. You should also remember to wear sunglasses and a hat, as UV rays are also harmful to hair and scalp. Finally, if you use loose-fitting or long clothing to protect yourself, remember to check its UPF (UV Protection Factor) rating, which measures its ability to let UV rays through. For example, a UPF rating of 25 means that the fabric only lets through about 1/25 of UVA and UVB radiation.