12 Ways the Sun Affects Us: Positive & Harmful

Wrinkles, sun burn, dehydration...the sun gets a bad rap for its negative effects on our health. However, sunshine is good for you when you’re careful. Sara Moeller, CAQ-Derm, PA-C, a dermatology provider at UnityPoint Health, says like many other things, sunshine should be enjoyed in moderation.

Positive Effects of the Sun

1. Enhances Your Mood

Moeller says there are many benefits from sunlight. It makes people feel better and have more energy. Sunlight also increases serotonin in the brain, which is associated with improved mood. Not surprisingly, serotonin levels are highest in the summer.

Tanning beds, however, aren't recommended as an alternative to the mood-boosting benefits of sunlight due to their major health risks.

2. Treats Seasonal Depression (Seasonal Affective Disorder)

In certain people, the lack of sunlight in the winter can trigger depression. Seasonal depression, also called Seasonal Affective Disorder (SAD), is rare in the warmer months. SAD symptoms include feeling down, difficulty making and keeping friends, overeating, tiredness and sleeping too much.

3. Relieves Stress

Everyone experiences stress for various factors, such as family, work and health issues. Moeller says stress can be relieved in a variety of ways, including exercise, having relaxing hobbies, walking the dog or by getting out in the fresh air for a little sun exposure.

4. Improves Sleep

Sunlight exposure impacts how much melatonin your brain produces, which is what tells your brain it’s time to sleep. When it gets dark, you start producing melatonin, so you’re ready to sleep in about two hours. With more sunlight in the summer, you’re likely to feel more awake. Moeller points out that modern technology has allowed us to change our light exposure artificially with lights, such as from TV, computer, tablet or phone screens. Consequently, insomnia is much higher now than it was before these devices were invented.

5. Vitamin D

Vitamin D is crucial for strong bones. You can get vitamin D from sunlight, but only 15 minutes of sun exposure per day is typically sufficient, according to Dr. Moeller.

The Harmful Effects of the Sun

6. Sun Damage to the Eyes

Prolonged sun exposure can harm your eyes. UV radiation can damage the retina, the part of your eye responsible for vision. It can also cause growths on the cornea and contribute to cataracts.

7. Heat Exhaustion

Heat exhaustion occurs when the body loses too much water and salt, typically through excessive sweating.

Symptoms of heat exhaustion include:

• Decreased urine output
• Dizziness
• Elevated body temperature
• Headache
• Heavy sweating
• Irritability
• Nausea
• Thirst
• Weakness

8. Heat Stroke

Heat exhaustion is a serious condition that can quickly escalate to heat stroke. If left untreated, body temperature can reach 106 degrees Fahrenheit within minutes, potentially leading to death or permanent disability. Call 911 immediately if you suspect heat stroke.

Symptoms of heat stroke include:

• Confusion, altered mental status, slurred speech
• Hot, dry skin or profuse sweating
• Loss of consciousness (coma)
• Seizures

9. Sunburn

Sunburns are widely recognized as one of the most common negative effects of too much sun exposure. Moeller says the maximum symptoms of sunburn don't usually appear until four or five hours after the sun exposure occurs. Ultraviolet light is the cause of sunburn, which may come from the sun or tanning beds. Contrary to popular belief, getting a base tan from a tanning bed won't protect your skin from getting sunburned either.

General symptoms of sunburn include:

• Blisters
• Flu-like symptoms, such as nausea, fever, chills or headache
• Pain/tenderness
• Redness
• Swelling

If you notice a sunburn fever, see your doctor. Besides a fever, severe burns also involve significant pain and extensive fluid-filled blisters.

10. Heat Rash

A heat rash is a skin rash that occurs when sweat ducts trap perspiration under the skin. Heat rash often takes place during hot and humid weather. It looks like red clusters of pimples or small blisters. Heat rash develops in skin folds, elbow creases, the groin or on the neck and upper chest.

Heat rash can be treated by staying in a cool environment to prevent sweating and by keeping the affected area of skin dry. To help relieve the symptoms of heat rash, use powder to increase comfort. However, it's not advised to use ointment or creams.

11. Skin Cancer

Moeller says the worst consequence of long-term exposure to the sun is the development of skin cancer. Because the sun damage to the skin develops over years, the older you are, the greater the risk of developing skin cancer. After years of exposure to the sunlight, providers look for three common types of skin cancer (in order of how often they occur): basal cell carcinoma, squamous cell carcinoma and malignant melanoma.

Basal Cell Carcinoma (BCC)

This type of skin cancer almost always occurs on sun-damaged skin and is usually pink, shiny and raised. Because the skin becomes very soft, it may be easily injured and so may appear as a scab that keeps returning in the same spot. Basal cell carcinoma is especially common in the beard area of men where they use a razor and take the top off the cancer. Although BCC doesn’t generally spread, it does get bigger and deeper over time and can become a problem if ignored.

Squamous Cell Carcinoma (SCC)

This skin cancer is primarily caused by sun exposure, but it can also develop in unexpected places, such as burn scars (from heat or radiation) and chronic skin ulcers. In a small number of cases, SCC can spread to the lymph nodes and (rarely) to other organs. Moeller says these skin cancers can vary in severity. In some cases, specialized surgical techniques, like Mohs surgery, are necessary for effective removal, particularly for larger or more complex lesions.

Malignant Melanoma

While less common than other skin cancers, melanoma rates are rising, particularly among young women aged 18-29 due to high tanning bed use.

Melanoma is very dangerous and can develop anywhere pigment-producing cells are found, including the entire skin, not just direct sun-exposed areas, as well as in moles, birthmarks and the eye. While melanoma doesn’t require direct sun exposure to form, sun exposure increases the risk. It can spread to lymph nodes and organs, including the brain, lungs and liver.

Melanoma is much more common in families with a history of abnormal moles or malignant melanoma. Those who've had melanoma have a significant risk of developing other melanomas, so Moeller recommends regular skin checks.

Early diagnosis is key for treating melanoma effectively. The smaller the tumor, the better the chances for successful treatment. While research continues, surgical removal of the tumor and any affected lymph nodes remains the cornerstone of treatment.

12. Wrinkles/Aging

We associate wrinkles with aging, but sun exposure affects how prominent and how early they appear. UV light damages collagen and elastic tissue in the skin, so it becomes fragile and won't spring back into shape, causing sagging. Moeller says the only factor worse than UV light exposure for aging and wrinkling is cigarette smoking, which causes the skin to become yellowish and thick with deep wrinkles. Some people get white cysts and blackheads on the cheekbones from sun exposure and smoking. UV light exposure also causes white and dark spots on the skin, as it damages the surface cells.

Why are Tanning Beds More Harmful Than the Sun?

While most people understand the importance of sun protection, many mistakenly believe indoor tanning is a safe alternative. This is a dangerous misconception, given tanning beds pose serious health risks. Here’s why:

• Intense UVA radiation: Tanning beds emit significantly more UVA radiation than the sun, penetrating deeper into your skin and increasing your risk of skin cancer.
• Skin damage: This intense exposure accelerates aging, leading to wrinkles and leathery skin.

Additionally, studies show the risk of malignant melanoma is much higher in people who use tanning beds. In the U.S., more than 400,000 cases of skin cancer are linked to indoor tanning each year.

The bottom line: Tanning beds are not a safe way to achieve a tan. Protect your skin and choose sun-safe methods for a healthy glow.

Protection from the Sun for Kids and Adults

Much of the damage to our skin caused by sun exposure can be prevented. Andrea Childs, DNP, CPNP-PC, UnityPoint Health, shares how kids and grown-ups can stay safe outside this summer.

Use sunscreen. Everyone, regardless of skin tone, needs to wear sunscreen, because all skin types are at risk for sun damage. Sunscreen must be applied 15-30 minutes before going out in the sun. It should also be reapplied at least every two hours and after swimming or heavy sweating.

When choosing a sunscreen, look for:

• SPF 30 or higher
• Sunscreen without bug repellant, because it may reduce effectiveness of sun protection if applied together. If bug spray is used, it should be applied separately, after sunscreen.
• Water and sweat-resistant varieties

The best sunscreen ingredients are zinc oxide or titanium dioxide, which are less irritating for those with sensitive skin or conditions like eczema.

In addition to sunscreen, practice the following sun safe tips:

• Find dense shade from a building, umbrella or tree
• Protect your eyes with UV filtering sunglasses
• Wear long sleeves and a brimmed hat that covers your face and neck

Sunscreen Ingredients to Avoid

Some research suggests certain sunscreen ingredients, such as oxybenzone, have potential health and environmental impacts. While more research is needed, studies show it may disrupt hormones and have harmful effects on coral reefs. Hawaii and other locations have banned the use of sunscreens containing oxybenzone and octinoxate.

Sunscreen Spray vs Lotion

Childs recommends lotions over sprays for better coverage. While sprays are convenient, lotions help ensure you apply sunscreen evenly, minimizing the risk of missed spots.

Sunscreen for Infants

The American Academy of Pediatrics doesn’t recommend sunscreen for infants under six months. Instead, they suggest keeping babies out of the sun, especially between 10 a.m. and 4 p.m., when rays are strongest.

If your baby is in the sun, keep them shaded or in clothing that covers their skin, face, ears and neck. If necessary, apply a small amount of sunscreen to exposed areas, but choose a mineral-based lotion that contains titanium dioxide or zinc oxide.