The Beatles once sang, “Here comes the sun / The smiles returning to their faces / It seems like years since it’s been here.” The famous foursome captured what we all know to be true: A sunny day just makes you feel good.
And it’s not all in your head. Sunlight plays a role in your overall health and well-being, says family medicine doctor Charles Garven, MD. So, it’s important to figure out how to benefit from those rays while also protecting yourself from the damage that too much sun can do.
“In general, you typically need much less direct sunlight than you might think,” Dr. Garven notes. “But even 10 to 30 minutes of sun exposure on bare skin can start to impact levels in a positive way.”
Dr. Garven outlines the specific benefits sunshine can bring, plus how much of it you need each day and how to soak it up safely.
Benefits of sunshine
Sunlight exposure provides essential vitamin D and helps boost everything from your mood and energy level to your ability to sleep well at night. What does that mean for your health? Let’s take a closer look.
Provides vitamin D
Sunlight is the main way that your body gets its vitamin D — so much so that it’s sometimes called the “sunshine vitamin”!
“More than 90% of our vitamin D comes from sunlight exposure,” Dr. Garven says. “The skin absorbs ultraviolet-B rays, which triggers the conversion of a cholesterol molecule in the skin into vitamin D3, the active form of vitamin D.”
Why exactly does that matter? Getting enough vitamin D is associated with:
· A healthy immune system
· Better mood
· Cardiovascular health
· Good muscle function
· Strong bones
“There remains considerable research out there to provide us with better information about each of those direct effects,” he adds, “but it’s clear that vitamin D is an important mineral for our overall health.”
Boosts mood
There’s a scientific reason why sunny days put a smile on your face: “Sunlight seems to activate a specific part of the brain called the pineal gland, which is related to the production of serotonin and other neurotransmitters,” Dr. Garven shares.
Serotonin is a neurotransmitter that carries messages between your nerve cells and throughout your body. This natural chemical is sometimes known as the “feel-good hormone” because of its effect on mood.
Getting more sunlight increases your serotonin levels, which, in turn, helps elevate your mood. A lack of serotonin, on the other hand, is thought to play a role in conditions like depression and anxiety.
Helps regulate sleep patterns
This might seem counterintuitive (after all, most people are awake when the sun is out!), but sunlight plays an important role in regulating your sleep cycle.
Your body’s internal clock, known as its circadian rhythm, relies on natural sunlight to stay in sync. When your eyes are exposed to light, your brain receives the message that it can stop producing melatonin — one of the main hormones that contributes to sleep.
“Getting sunlight early in the day helps signal to your brain that it’s time to be alert,” Dr. Garven explains. “While darkness tells your brain that it’s time to get ready to sleep.”
Improves symptoms of seasonal depression
Seasonal affective disorder (SAD) is a type of depression triggered by a change in seasons and often triggered by a lack of sunlight.
“We know that sunlight is related to seasonal affective disorder, and there is likely some interplay between that aspect of mood and serotonin,” Dr. Garven points out.
An increase in sunlight has been shown to have a positive impact on symptoms associated with seasonal depression. A 2024 study reports that spending more than one hour in daylight during winter protected against depression symptoms. And in an older study, people with SAD who took a one-hour walk outdoors each morning for a week reported a 50% improvement in their symptoms.
Contributes to overall well-being
Sunlight exposure has been shown to improve:
· Energy levels
· Physical performance (namely muscle function)
· Sleep quality
· Stress and anxiety levels
Cognitive function
“Sunlight has been shown to activate a variety of parts of the brain, though we know more about some of them than about others,” Dr. Garven acknowledges. Research is ongoing into all of these benefits, but one thing is clear: A little bit of sunlight can go a long way.
How to get enough
Not all time spent outdoors is created equal. Five minutes in the sun on a summer afternoon in Florida, for example, is not akin to five minutes outside on a gray winter morning in Ohio.
Dr. Garven says the right (and safe) amount of sun exposure for you will depend on factors like:
· Your skin tone
· Your geographic location
· The season
· The time of day
Because these factors are so individualized, it’s always best to ask your healthcare provider how much sunlight is safe for you.
And a big word of caution: Don’t forget about sun safety! Though UVB rays have some important benefits for your mood and vitamin D levels, they can also quickly damage your skin and raise your risk of skin cancer.
“As with most things in medicine, moderation is key,” Dr. Garven emphasizes. “There’s always such a thing as too much of a good thing.”
Avoid the blazing midday sun, wear sunscreen and don’t overestimate how much sunlight you need to boost your vitamin D and your mental health, as it can very quickly shift into bad-for-your-skin territory.
