Warm weather often makes us eager to get outside and soak up the sun, whether by lying back on the beach, hiking in the mountains, or simply enjoying a leisurely walk in the park.

But while our star provides us with warmth, light, and vitamin D, it also emits ultraviolet radiation, which can have a potentially detrimental impact on our health. That’s why understanding these rays and their effects is crucial to enjoying the outdoors safely this season and beyond.

The different categories of UV rays

UV radiation is a type of energy that falls into three categories: UVA, UVB, and UVC. Each one has varying wavelengths and ability to penetrate the atmosphere, meaning they can affect you in different ways.

UVA
These rays possess the least amount of energy but have the longest wavelengths. As a result, they make up the majority of the UV radiation that reaches the earth’s surface. Despite their lower energy, UVA rays penetrate deep into the skin, degrading collagen and elastin fibers over time. Both of these are essential for maintaining the skin’s structural integrity and elasticity, and damage to them leads to the development of wrinkles and fine lines as well as a general loss of skin firmness, making UVA rays a major contributor to premature aging.

UVB
In contrast, UVB rays have more energy yet shorter wavelengths. This means that although fewer of them reach the earth, they are more intense and have a greater potential for harm. UVB rays are the primary cause of sunburn because they impact the epidermis, the skin’s outermost layer, and can cause DNA mutations within skin cells. This is a key factor in the development of skin cancers, including various carcinomas and melanoma, the most dangerous form of skin cancer. Tanning beds are another source of UVB rays, exposing users to higher concentrations of them and increasing their risk for such health issues.

UVC
While these rays are the most energetic of the UV spectrum, they fortunately do not reach the earth’s surface since they are completely absorbed by the atmosphere. However, UVC rays can still pose a danger through artificial sources. Devices such as welding torches, mercury lamps, and UV sanitizing bulbs all emit UVC radiation, which can cause severe burns and other injuries if proper precautions are not taken.

The good

Despite the potential dangers of UV exposure, there are beneficial aspects. UVB rays, for instance, play a particularly important role in vitamin D production, which is essential for maintaining healthy bones and a robust immune system. The World Health Organization recommends brief, unprotected sun exposure two to three times a week for about twelve minutes, or roughly half the time it would take for your skin to begin burning. (This may vary depending on your skin’s sensitivity and the UV index on a given day.) This allows your body to synthesize adequate levels of vitamin D without significantly increasing your risk of skin damage. Moreover, sunlight is a known mood booster due to its ability to increase serotonin levels. That’s why spending time outdoors is a common suggestion for people who suffer from seasonal affective disorder. So if you’re looking for a quick pick-me-up during the week, get outside for a brief moment—you may be surprised at the difference it can make.

Though sunlight is essential for life and provides important health benefits, it also presents risks that shouldn’t be ignored. By taking the appropriate precautions, such as wearing sunscreen, staying in the shade, and avoiding exposure during peak hours, you can enjoy the sun safely, reaping its benefits while minimizing its harmful effects.