
Now, before we start bashing on the sun, just know this: Studies have shown sunlight is, on the whole, not bad. Getting a decent amount of rays boosts your mood, keeps your bones strong, and helps fight off autoimmune diseases—all thanks to a certain super-charged nutrient: Vitamin D. That said, despite the myriad benefits of this do-it-all vitamin, too much exposure to sunlight is yet another case of "too much of a good thing."
You're well aware of sunburns, of course, but ultraviolet rays can wreak even more havoc on your body, and can even inflict irreversible damage to your eyes, heart, and lungs. So if you plan on lounging on the beach, the lawn, the roof, the porch, or even just by the pool this summer, be sure to keep an eye out for these potentially serious inflictions. And for more ways to live your best life this summer, don't miss the 100 Motivational Weight-Loss Tips for Summer.
1
It Can Cause Skin Cancer
This is one of the most obvious ways the sun can harm your health, but it needs to be repeated—especially since people are still hitting up tanning beds in 2018. Despite overwhelming, widespread evidence that everyone under the sun should protect their skin, one person still dies of melanoma every hour, says the Skin Cancer Foundation—and that's not even including the 5.4 million cases of non-melanoma skin cancer treated every year. To help prevent the disease, learn the 20 Skin Cancer Symptoms Everyone Needs to Know.
2
It Can Damage Your Vision
You know how your mom always told you to avoid looking at the sun? Well, she had a point: it can seriously damage your retina, the part of the eye that's responsible for the center of your vision. According to UnityPoint Health, that ultraviolet light can cause some serious damage, messing with your eyesight—and no, not just during solar eclipses.
3
It Can Cause Skin Damage
Melanoma is one thing, but the sun can also just straight-up damage your skin—even after a short time period without proper sun protection. "Skin cancer is the extreme of skin aging, but before that, you can certainly get lines, wrinkles, freckles, broken capillaries—all signs of damage. You're aging your skin faster every time you go outdoors without sunscreen," said Darrell Rigel, MD. And for more ways to arm your skin against the sun, check out these 15 Hacks to Apply Your Sunscreen More Easily.
4
It Can Cause Heat Stroke
If you've spent too long out in the sun, you could come down with a case of heat stroke. According to the Centers for Disease Control and Prevention (CDC), it occurs when your body can no longer control its own temperature, becoming incredibly high and unable to cool off. What's more, it can happen so quickly that your body temp could shoot up to 106º Fahrenheit in as little as 10 minutes, possibly resulting in serious injury or death if you're not treated quickly enough.
5
It Can Cause Sun Poisoning
When you get too much sun, you're left with red, painful skin—and even though that sunburn might seem minor, it can still lead to skin cancer. Severe sunburns and sun poisoning, on the other hand, take things up another notch, resulting in blisters, bumpy rashes, a fever and chills, nausea, and dizziness that needs to be treated by a doctor, says Advanced Dermatology. And for more habits to avoid during the summer months, check out these 15 Biggest Health Mistakes People Make in Summer.
6
It Can Cause Dehydration

After spending all day outside in the sun with little water, it's not uncommon to become dehydrated—it can happen even when you're not in the sun. Because of that, you could experience fatigue, dizziness, confusion, and other not-so-fun symptoms that, depending on how severe they are, could require getting an IV to replenish your fluids, says John Hopkins Medicine.
7
It Can Give You Headaches and Migraines
For some people, a headache or migraine could simply be triggered by the sun. According to the American Migraine Foundation, one of the most common factors is a sun glare, which can easily induce that awful head-throbbing. To help prevent sun-related head pain, wear hats that keep those bright rays out of your eyes and off your neck, chest, face, and back.
8
It Can Cause Cataracts

Sunglasses aren't just for looks—they also do a lot of good in protecting your peepers. According to the United States Environmental Protection Agency, UV radiation has been shown to increase your risk of cataracts, a type of eye damage that clouds your vision or leads to blindness. To keep yourself safe, wear sunglasses with 99 to 100 percent UV protection.
9
It Can Trigger an Allergy
Erythropoietic protoporphyria might be rare, but it's not fun if you happen to have it. The condition—which is basically a sun allergy—results in swelling, burning, itchy, and red skin during or after time spent in the sun. Even though the symptoms go away within a few days, it's still incredibly uncomfortable, says the American Porphyria Foundation.
10
It Can Mess With Your Breathing

Spending too much time out in the sun doesn't just burn your skin and make you dehydrated. It can also mess with your breathing. If you're suffering from a heat stroke, your breaths can become very rapid and shallow, says the Mayo Clinic—something that can be incredibly scary and life-threatening to go through.
11
It Can Cause Heat Exhaustion

While heat stroke is terrifying enough, another serious illness the sun causes is heat exhaustion. According to the CDC, it happens when your body has sweat so much that it has lost excessive amounts of its water and salt, making you come down with a headache, nausea, dizziness, and other symptoms that require medical attention.
12
It Can Suppress Your Immune System

There are many things that can suppress your immune system—hello, stress!—and the sun is one of them. When you get too much UV radiation, your immune system can no longer function properly, making it weak and limiting your skin's ability to protect itself from things like cancer and infections, says the EPA. Since you want your body to be as strong as it possibly can to help you stay healthy, slather on that sunscreen and stay out of those rays for long periods of time.
13
It Can Cause Melasma
Listen up, ladies—especially if you take birth control, are pregnant, or are dark-skinned. Melasma occurs from a combination of sunlight and an increased supply of estrogen and progesterone, leaving you with dark patches on your cheeks and forehead, says the Mayo Clinic. And although it affects nearly 5 million Americans, the International Dermal Institute says it's incredibly hard to treat because it deals with a change in skin pigmentation.
14
It Can Make Your Heart Race

When it's hot and sunny out, your heart has to heat faster and pump harder to make sure your blood is flowing properly through your veins—and according to Harvard Medical School, that could mean it's circulating up to four times as much blood per minute than it would on a nice, cool day. Because of that, people with heart conditions might want to take it easy to prevent dizziness or falling due to the increased blood flow.
15
It Can Cause Actinic Keratosis
When you spend too much time out in the sun, you could experience actinic keratosis, which are scaly, crusty growths on your skin. It might not seem like a problem, but don't let them just go away on their own: although they're not cancerous (yet!), they're considered a pre-cancer and could possibly develop into skin cancer if you don't have it removed by your derm, says the Skin Cancer Foundation.
16
It Can Cause Pterygium
Sorry, but the eye issues continue. Another UV-related problem that can occur is pterygium, a tissue growth that starts in the corner of the eye and can spread to the cornea, harming your vision, says the American Academy of Ophthalmology. It's common in those who work outdoors or who surf a lot, usually resulting from all that sun combined with dry eyes from wind and dust.
17
It Can Cause Heat Syncope

Spending time outdoors in the heat and sun can result in heat syncope, which causes you to faint due to not having enough blood flow to the brain. To make sure it doesn't happen to you, stay hydrated and make sure you're wearing clothes that block those UV rays, keeping yourself cool, says the University of Connecticut.
18
It Can Give You Cramps

Heat cramps are a thing, and they're definitely not fun. If you've been outside in the sun and in hot temps, there's a good chance your body will lose salt and fluid due to all that sweating—especially if you're doing something strenuous, like heavy labor or working out, says the Mayo Clinic. Because of the lack of salt, you could experience painful cramping and muscle spasms that gently need to be massaged out.
19
It Can Give You a Heat Rash
Not to be confused with a sunburn, a heat rash happens when you spend too much time in the sun sweating, which irritates your skin and causes a red cluster of pimples or blisters. According to the CDC, the rash usually occurs in extra-sweaty areas like the groin, under the breasts, in elbow creases, and on the neck or upper chest. It can be treated by applying a powder and keeping the area dry.
20
Macular Degeneration
Macular degeneration is the number one cause of vision loss. It happens when the central part of the retina deteriorates, making it hard to read, drive, and even recognize faces, says the American Macular Degeneration Foundation. And while it develops as the eyes age, the exact cause isn't known—but a 2013 study published in the British Journal of Ophthalmology found those who have more sunlight exposure are at a "significantly increased risk," so put those sunglasses on ASAP. Summer isn't the easiest season on your overall health and well-being, which is why we made our list of the 30 Worst Things about Summer.
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