Ever wondered why your skin turns red and painful after a day in the sun?
It’s actually your body’s way of dealing with damage from ultraviolet (UV) light.
Jean-Philippe Pellois, a biochemistry expert at Texas A&M University, explains the science behind sunburns and why they’re both necessary and harmful.
What Causes Sunburns?
UV light is a type of high-energy light that’s invisible to the human eye.
According to Pellois, this energy is so strong it can break molecules in your skin, especially DNA.
When DNA gets damaged, cells try to repair it. But if the damage is too severe, cells will self-destruct in a process called apoptosis, or programmed cell death, to prevent becoming unstable or dangerous.
This process is different from a thermal burn caused by fire or hot water, where cells die from immediate damage. With sunburn, the cells die because they choose to self-destruct due to DNA damage.
As these cells die, blood vessels in the skin widen to let immune cells reach and remove the dead cells, causing the redness we associate with sunburn. This inflammation, along with the body’s effort to replace the damaged skin, leads to peeling.
Factors Affecting UV Sensitivity
When cells survive UV exposure but are heavily damaged, they can sometimes become problematic.
If one of these damaged cells starts growing uncontrollably, it could potentially form a tumor and lead to skin cancer. While a single sunburn rarely causes this, repeated damage increases the risk over time as mutations accumulate in the DNA.
Our bodies can adapt to some extent. For example, skin cells produce more melanin when exposed to UV light. Melanin is the pigment that tans the skin and provides some protection by absorbing UV light and converting it into a harmless form. People with more melanin have better natural protection against sunburn.
Sunscreens also help protect the skin. Chemical sunscreens absorb UV light and convert it to a safer form, similar to melanin. Mineral sunscreens, containing zinc oxide or titanium dioxide, act as physical barriers that reflect UV light away from the skin.
Other factors, like the antioxidants in your diet, can also influence how sensitive you are to UV exposure. Pellois emphasizes that while our cells are good at repairing damage, it’s best to avoid getting sunburned in the first place.
Take Care of Your Skin
Understanding the science behind sunburns can help us take better care of our skin.
Using sunscreen, wearing protective clothing, and limiting sun exposure are all ways to prevent the harmful effects of UV light. Your body works hard to protect you, so give it a hand by staying safe in the sun.
If you care about skin health, please read studies about top signs of diabetic skin disease, and Mediterranean diet could help lower the skin cancer risk.
For more information about skin health, please see recent studies about eating fish linked to higher risk of skin cancer, and results showing how to combat the effects of aging on your skin.
