Benefits of Sunlight for Mood, Healthy Bones and Immunity - Dr. Axe

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Benefits of Sunlight for Mood, Healthy Bones and Immunity


Sunlight - Dr. Axe

We often talk about how to protect yourself from the sun and even the dangers of UV rays, but the benefits of sunlight deserve lots of attention, too. In fact, too little of it can lead to mood issues, fatigue and vitamin D deficiency.

Researchers have even warned that the recommendations to avoid sunlight can actually cause more harm than good.

A 2020 review published in the International Journal of Environmental Research and Public Health states that “insufficient sun exposure has become a real public health problem.” Data from past studies also shows that not getting enough natural light may be responsible for 340,000 deaths in the United States and 480,000 deaths in Europe per year — along with an increased risk of cancer, metabolic syndrome, Alzheimer’s disease and cardiovascular disease, among other major health issues.

Beyond allowing for the synthesis of vitamin D, sunlight benefits mood and boosts happy hormones like serotonin. Without it, we risk cognitive decline and greater susceptibility to disease.

So before covering up and reapplying your sunscreen, be sure you are getting the minimum amount of sunshine in your day.

Top 7 Benefits of Sunlight

You know that feel-good moment you always get when sitting in the sunlight? Well, there’s a reason for that.

Here’s a breakdown of the top benefits of sunlight for your mental and physical health:

1. Boosts Cognitive Function

For a 2009 study published in Environmental Health, data from 16,800 participants was analyzed to research the relationship between sunlight exposure and cognitive function. Researchers found that among depressed participants, lower levels of sunlight were associated with impaired cognitive status.

The study indicates an association between decreased exposure to sunlight and increased probability of cognitive impairment.

2. Fights Depression

One of the most well-known benefits of sunlight is its positive effect on your mood. Research published in Issues in Mental Health Nursing states that the treatment of inadequate vitamin D levels in people with depression and other mental disorders may be “an easy and cost-effective therapy which could improve patient’s long-term health outcomes as well as their quality of life.”

Sunlight exposure has shown to increase serotonin levels, which is associated with better mood. Low serotonin levels are associated with seasonal affective disorder, a form of clinical depression that comes and goes in a seasonal pattern.

3. Supports Better Sleep

Studies indicate that there’s a relationship between sunshine and serotonin, a brain chemical that plays a role in mood regulation and many body processes, including sleep.

Another study found that sun exposure plays an important role in maintaining regular circadian rhythm and, because it’s involved in the production of vitamin D, regulates various functions in the body that support restful sleep.

4. Supports Immune System Health

Vitamin D performs several roles within the immune system. Studies suggest that vitamin D deficiency is associated with poor immune function and increased disease susceptibility.

Vitamin D benefits include its role in healthy cell replication and its protective effects against autoimmune conditions.

5. Promotes Bone Health

Vitamin D is critical for bone health, and studies show that a deficiency is an important health concern. Adequate sun exposure is needed to maintain proper vitamin D levels and optimal bone health, according to researchers.

6. Promotes Longevity

Evidence published in the International Journal of Environmental Research and Public Health cited above suggests that it would be beneficial for people living outside of the tropics to ensure they expose their skin to the sun sufficiently. A lack of sunlight can cause vitamin D deficiency and increase the risk of several major health concerns, including cancer, heart disease and osteoporosis.

Getting adequate sun exposure promotes longevity and improves your mood and feelings of happiness.

7. May Help Fight Cancer

Research published in the Journal of Cosmetic Dermatology points out that vitamin D is derived from solar ultraviolet light exposure, and there’s evidence that low levels of vitamin D can increase the risk of 16 different types of cancer, including breast, ovarian and prostate cancers.

How to Get More Sunshine

How much sunlight do you need per day? This depends on your skin type and the UV index in the area you live, but a general rule of thumb is getting five to 15 minutes of direct sunlight at least three times per week, when possible.

In summer months when the index is very high, you can wear sunscreen on your face and other sensitive areas to avoid sunburn, but let your arms and legs soak up the sun for that period of time. During colder months, you can spend a longer period of time in direct sunlight without the risk of burning.

While getting adequate sun exposure is vital to human health, it’s also important to avoid getting a sunburn. Researchers suggest getting no more than five to 30 minutes of direct sun exposure (depending on your skin type and the UV index) during high ambient UV ray seasons to avoid sunburn.

What about indirect sunlight or using a sunlight lamp? When in comes to boosting your mood and promoting better sleep, getting indirect sunlight is beneficial, too.

Sitting by a sunny window definitely has its advantages, for example. If you don’t have access to natural sunlight, using a sun lamp or light therapy box is an effective alternative.

One study found that light therapy is an effective treatment for seasonal affective disorder and has benefits after only 20 minutes of use, which continue for up to 60 minutes.

Risks and Side Effects

Exposure to light at night strongly suppresses melatonin, which can interfere with sleep timing and sleep quality. Sources of indirect sunlight may interrupt circadian rhythm and result in sleep disruption.

When it comes to using a sun lamp, excessive use may cause adverse effects, including eyestrain, headache and nausea. If this occurs, reduce the amount of time you use the lamp per day.


  • There’s something very comforting and energizing about sitting in the sunlight. It leaves us feeling refreshed and boosts our mood, but that’s not all sun exposure does for our health.
  • Sunlight benefits really come from the production of vitamin D, which plays a critical role in immune system health, bone health, proper sleep and more.
  • You should aim to get five to 15 minutes of direct sunlight per day, depending on your skin type and the UV ray index. If you don’t have access to direct sunlight, try sitting by a sunny window or using a sun therapy light.

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