You need to get outside and spend time in the sun to be healthy. All the doctors say it. But, if you get too much sun, that’s also bad.
After all, no one wants a sunburn. Even worse, skin cancer is a real threat, and it turns out that getting sunburns dramatically increases cancer risks. What is a person to do?
With a little knowledge, you can spend a lot of time in the sun while mitigating burns and cancer risks. Here are four bits of knowledge that will help.
Sunburns come from the UV light in sunlight, and UV is ionizing radiation. It’s dangerous for the exact same reasons as x-rays, so radiation safety rules apply. Here are the three rules of radiation safety:
- Maximize distance
- Use shielding
- Minimize exposure time
We’re assuming you’re on earth, so you can’t really change your distance from the sun. That means you need to focus on shielding and exposure time. Shielding comes down to the stuff you already know: sunscreen, hats, clothing, and sunglasses.
So, the real lesson here is exposure time. The longer you are in the sun, the more you burn, but there’s a trick. If you can break up sun exposure with periods of rest, your skin can recover from minor sun damage and reduce the risk of sunburn. If you’re working in the yard, take cover in the shade every 10 minutes or so until your skin no longer feels like you’re glowing.
If you’re hiking, bring an umbrella or other good source of shade. Every time you stop for rest, get in the shade.
You’ve probably heard of polarized sunglasses, but do you know what they do?
They actually employ a principle of quantum optics. Light travels in waves, but those waves can be oriented in any different direction. Polarized filters basically block any light that isn’t oriented correctly.
In effect, polarized filters block about half of all light (including UV). When they are combined with additional protection (like the tint in your sunglasses), then they’re adding a powerful layer of sun protection.
This is why polarized sunglasses are much better for your eyes, but there’s another trick. Did you know that polarized clothing exists? You can get polarized clothes that offer enhanced sun protection if you’re sensitive. Or, you can get clothes that let a little more UV through, allowing you to gently take in sunlight for natural vitamin D and melanin production.
Food and Drugs
Things you imbibe or put on your skin can change your UV sensitivity. Obviously, a higher sensitivity will lead to faster and more severe sunburns, so let’s look at what you might need to avoid.
There are more than a few foods and supplements that can increase UV risks:
- St. John’s wort
- Ginkgo biloba
- Topical vitamin C
- Scented soaps and perfumes
- Glycolic acid
- Retinols, benzoyl peroxide
- Artificial sweeteners
This is not an exhaustive list, but those are some of the most common troublemakers.
There are also medications that can increase solar sensitivity:
- Antifungal medications
- Oral contraceptives
- Hormonal treatments
Again, this doesn’t cover absolutely everything. The simple lesson is if you’re having trouble with sunburns, talk to your doctor to see if a change to diet, supplements, or medications can help.
Lastly, you need to know a little bit about how sunlight works if you really want to beat it. First, not all sunlight is equal. You can make great use of the UV index to figure out what days and times put you at the highest risk.
Beyond that, it helps to know that UV is more intense near the equator and at higher elevations. That’s because in either case, there’s less atmosphere absorbing UV photons before they can get to you.
Also remember that sunlight reflects off of surfaces. Even in the winter, skiers often get bad sunburns because so much UV bounces off of the snow (and they’re on top of mountains). Lakes, metal surfaces, and even light-colored sand are all highly reflective.