How Much Sun Is Too Much? Reducing Your Skin Cancer Risk

Whether you're taking a walk, running errands or playing with your dog, enjoying the sunshine can feel great and give you a boost. But it’s important to note — no matter your skin tone —that anything more than 10 to 30 minutes out in the sun without sun protection can be too much sun. A sunburn can potentially increase your risk of skin cancer.

Let’s talk more about how much sun is too much, when sun exposure can be harmful and ways to get much-needed vitamin D while still protecting your skin.

How Much Sun Is Considered Too Much?

Generally speaking, if you're spending time outdoors on a sunny day without any type of skin protection, your skin can start to burn anywhere between 10 and 30 minutes.

For people with lighter skin, just 10 to 20 minutes of sun exposure can cause skin to redden and possibly burn. People with darker skin may be able to stay out in the sun longer — 25 to 40 minutes — without protection; however, there's still a high risk of skin damage.

According to the U.S. Environmental Protection Agency (EPA), the sun's rays are the strongest between 10 am and 4 pm every day.

Two types of UV rays can be harmful to your health:

• Ultraviolet A (UVA) radiation is responsible for skin aging, including wrinkles, sunspots and collagen breakdown. Overexposure to UVA can also damage the eyes and suppress the immune system, making the body more prone to infections.
• Ultraviolet B (UVB) rays can cause sunburn and are considered the primary cause of most skin cancers.

It's important to remember that even on a cloudy day, both UVA and UVB rays can penetrate and cause sunburn and other skin damage if you're not properly protected.

Why Sun Exposure Can Be Harmful

Now that you have a better idea of how much sun is too much on unprotected skin, let’s discuss why sun exposure and sun damage can be dangerous to your health.

First, it's important to understand that everyone needs a bit of sun exposure as it can provide some health benefits, including:

• Helping to regulate the body's circadian rhythm, or sleep-wake cycle, which is vital for quality sleep and general wellness
• Increased serotonin production in the brain, which is vital for regulating your mood and helping to reduce stress and anxiety
• May support heart health by helping lower blood pressure by releasing nitric oxide into the bloodstream
• Prompting the body's production of vitamin D, which supports bone health, immune function, healthy muscle movement and the well-being of the brain and nervous system
• Reinforcing the body's immune system, as vitamin D leads to more production of white blood cells

Even with its many benefits, the sun can become harmful when you’re outside for a longer period of time without any sun protection, whether that’s sunscreen, shade or UV-protective clothing.

When the sun's UV radiation hits your skin, it damages the DNA of the skin's cells, which can lead to:

• Premature skin aging issues, such as wrinkles, fine lines, skin sagging and age spots
• Types of skin cancers, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and melanoma
• Sunburn, which causes the skin to become red and painful, and may blister or peel

Additionally, UV radiation can harm unprotected eyes, regardless of melanin levels, increasing a person's risk for:

• Cataracts
• Eye cancers, including ocular melanoma or skin cancer on the eyelid
• Irritated and watering eyes
• Macular degeneration
• Photokeratitis (sunburn on the cornea)
• Photophobia (sensitivity to light)
• Pterygium (known as surfer's eye, a noncancerous growth over the white part of the eye)

Additionally, excessive sun exposure can lead to conditions like heat exhaustion or heat stroke, regardless of skin type, both of which require immediate attention. When your body becomes overheated after prolonged sun exposure, you may experience common heat exhaustion symptoms, including:

• Clammy skin
• Feeling of faintness or dizziness
• Major sweating
• Muscle cramps
• Nausea or vomiting
• Rapid pulse

Heat exhaustion is usually treated through:

• Lying down and resting on your back, sometimes with your legs raised
• Rehydration through electrolyte drinks or cool water
• Removing any form-fitting clothing or heavy clothing
• Seeking out a way to cool the person down, through the use of shade, ice, fans or air conditioning

If your heat exhaustion symptoms don't improve within 30 minutes of treatment, you should seek medical attention.

The following symptoms are more severe and can be a sign of heat stroke, a potentially life-threatening condition that requires immediate medical attention:

• Body temperature above 103 degrees Fahrenheit
• Confusion
• Hot, red and dry skin
• Loss of consciousness
• Nausea or vomiting
• Seizures
• Severe headache
• Very rapid heartbeat

If you suspect you or a loved one is experiencing heat stroke, it’s important to take action right away. Call 911 or go to the nearest emergency room.

Sun Exposure and Skin Cancer Risks

Some people have a higher risk of developing skin cancer, including those who:

• Are genetically predisposed to skin cancer
• Have a long history of sunburns, especially during childhood
• Have very fair skin that burns or freckles easily
• Live in a high-altitude area, placing them closer to the sun
• Work or play outside constantly

You can also watch for potential signs of skin cancer at home, such as:

• A new spot on your skin
• A bump that looks like a wart
• A sore that doesn't heal
• Changes to an existing mole's shape, size or color
• Scaly-feeling red patches
• Shiny spots that are red or skin colored

If you notice any of these signs or think you may be at high risk for skin cancer, schedule an appointment with an AdventHealth dermatologist who can provide you with a full skin examination and talk to you about ways to reduce your risk.

Getting Vitamin D Without the Risk

If you're concerned about your risk of skin cancer, there are other ways to get the benefits of sun exposure without spending too much time in the sun.

For instance, you can prevent vitamin D deficiency by:

• Consuming foods high in the nutrient, including mushrooms, egg yolks, beef liver and fatty fish like salmon
• Eating foods fortified with vitamin D, such as orange juice, cereals and dairy products like cow's milk, soy milk and yogurt
• Taking a daily vitamin D supplement

It's also possible to increase your body’s vitamin D production through healthy direct sun exposure. Spend only brief periods in the sun, 5 to 15 minutes a few times a week during the early morning or late afternoon, while still covering up at least 25% of your body’s exposed skin and wearing sunscreen.

When you're out in the sun, make sure to protect your skin by:

• Checking the UV index for the day to know the intensity of the sun’s rays
• Limiting exposure based on the time of day when the sun is at its peak to limit UV exposure
• Wearing a wide-brimmed hat with a brim that goes all the way around your head to help shade your face, ears and neck and other cover-ups on sensitive areas
• Wearing long-sleeved shirts, pants or skirts, preferably made of UV-resistant fabrics
• Wearing sunglasses that block both UVA and UVB rays
• Using broad-spectrum sunscreens with an SPF 30 or higher — choose a water-resistant sunscreen if you'll be in the water or sweating heavily — and remember to reapply sunscreen at least every two hours

These simple sun-safety habits allow you to enjoy the benefits of time outdoors while protecting your skin and long-term health.

Caring for the Skin You're In

Protect your long-term wellness inside and out by practicing sun safety and caring for your skin. For more practical tips and expert guidance, schedule an appointment with one of our skincare specialists. Find dermatology care near you today.