From The Desk of Josh Gitalis

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A sunny day is often all we need to make us smile and most of us prefer the sun’s rays to cold, snowy or rainy weather. The sun isn’t just a star that can make our daily activities brighter; without it, life as we know it wouldn’t exist. As the source of life on earth, the sun is vitally important to all life forms but in particular, sun exposure has a wide array of health benefits for us.

The Sunshine Vitamin: Vitamin D

It’s impossible to examine the health benefits of sunshine without first discussing Vitamin D. Nicknamed ‘the sunshine vitamin’, Vitamin D is produced in the skin by cholesterol after it comes in contact with the sun. It behaves more like a hormone than a vitamin, and is essential to bone and dental health, calcium absorption and mineral balance, proper immune function, hormone production, cognition, and heart function.

While there are some dietary sources of Vitamin D, including fish, eggs and mushrooms, the sun is one of our best sources of Vitamin D (plus it’s easily available and free). Astoundingly, nearly half of the world’s population has a Vitamin D insufficiency and about 1 billion people suffer from a Vitamin D deficiency. Some of the main reasons for this are spending less time outside in the sun, and using sunscreen when we do.

The Health Benefits of Sunshine

There are many reasons to get outside and enjoy the sun safely. Some of these health benefits of sunshine may surprise you!

Reduced Cancer Risk

Our main fear of sunshine stems from the potential risk of different kinds of skin cancers. And yes, we can be at a greater risk of melanomas if we perpetually experience sunburns, which cause damage to our skin and DNA. However, sunburns and sun exposure are not the same thing. It’s possible to experience the sun safely (more on that below) and reduce the risk of several different cancers. A review of ecological studies of cancer rates in over 100 countries found that UVB exposure can decrease the risk of the following cancers:

  • bladder
  • breast
  • cervical
  • colon
  • endometrial
  • esophageal
  • gastric
  • lung
  • ovarian
  • pancreatic
  • rectal
  • renal
  • vulvar cancer
  • Hodgkin’s and non-Hodgkin’s lymphoma

The same study noted weaker, but existing, evidence that the sun may curtail the development of these cancers:

  • brain
  • gallbladder
  • laryngeal
  • oral/pharyngeal
  • prostate
  • thyroid
  • leukemia
  • multiple myeloma

Even skin cancer (melanoma) may be ameliorated by the sun: some studies have shown that sun exposure can actually improve melanoma survival. Researchers are continually finding evidence that links Vitamin D and cancer prevention, likely due to its important effect on the immune system.

A Better Night’s Sleep

Sleep is crucial for rest and recovery, yet many of us struggle with insomnia, sleep deprivation or a poor night’s sleep on a regular basis. Historically, humans rose and slept with the rise and fall of the sun; now our schedules aren’t as connected to the sun’s natural rhythms. Evidence shows that sun exposure can help to regulate our circadian rhythm, which is also known as our internal clock or our sleep/wake cycle, and enhances the quality and pattern of sleep. This is especially true in older adults and seniors, who often have problems with sleep.

Sunlight, especially first thing in the morning, helps us produce melatonin more quickly at night to help us fall asleep faster. Sun exposure triggers serotonin as well, the precursor to melatonin, which is a neurotransmitter associated with sleep, mood and anxiety.

Improved Mental Health

Decreased exposure to sunlight – particularly in the winter – is linked to Seasonal Affective Disorder (SAD) and lower serotonin activity, which can negatively impact mood and mental outlook. A lack of sunlight can also impair cognitive function and increase the risk of depression and schizophrenia.

Sunshine lifts the production of Vitamin D and other hormones that can help boost your mood, alleviate depression, increase endorphins and improve your mental outlook. More sunshine is also associated with lower cases of suicide.

Better Cardiovascular Health

Direct sun increases our production of nitric oxide, a vasodilator that widens the blood vessels and helps lower blood pressure and cholesterol. Sunlight can also reduce additional risk factors for cardiovascular disease such as obesity, Type 2 diabetes, inflammation and metabolic syndrome.

A contributing factor here is sunlight’s trigger of Vitamin D – studies have found that people living in northern latitudes have a greater risk of hypertension, while those with cardiovascular disease are more likely to be Vitamin D deficient.

Higher Cognitive Function

Yes, the sun can make you smarter! A study of nearly 1,200 seniors living in rural China investigated two groups of people: one with long-term, high amounts of sun exposure and another with short-term, low sun exposure. The higher sun group showed better cognitive function and performed better on tests than the low sun group.

A Happier Work Environment

Employers are always looking for ways to improve employee health and wellbeing, and part of the answer might be sunshine. Researchers collected data from 444 employees in the United States and India and studied their exposure to direct sunlight (being outside), indirect sunlight (light through a window) and ‘natural elements’ (window views, plants, nature-themed decor, spending time outside). The findings showed that direct sunlight decreased anxiety, while both direct and indirect sunlight created higher job satisfaction and commitment to the company or organization.

Another study of office workers found that employees in workspaces with windows and daylight experienced better sleep, exercised more and reported an overall better quality of life than those who worked in windowless rooms. You can find more tips to help you cultivate workplace health here.

Autoimmune Disease Protection

Direct sunlight can help to activate the immune system and improve Vitamin D status, and has been shown to protect against certain autoimmune diseases such as Type 1 diabetes, rheumatoid arthritis, multiple sclerosis and inflammatory bowel disease. As one example, women who live in lower latitudes have a lower risk of Crohn’s disease and ulcerative colitis than those living at higher latitudes. Researchers have also found that low sun exposure increases the risk of MS, and that those with rheumatoid arthritis are more likely to be Vitamin D deficient.

Longer Life Expectancy

Spending time in the sun may help you live longer. Several meta-analyses have found that higher sun exposure and Vitamin D levels reduced the risk of all-cause mortality (any cause of death) including cancer, cardiovascular disease, and other causes.

Increased ATP Production

We know from elementary school that plants absorb the sunlight and transform it into the food that sustains them. Emerging evidence indicates that we might be able to do something similar. We can take the sun’s rays and, with the help of chlorophyll, produce ATP – the energy currency of our bodies.

How Much Time Should I Spend In the Sun?

The optimal amount of sun exposure depends on multiple factors, including the time of year, where you live, age and race. Generally, it’s best to avoid being in the sun for long stretches during peak times, which can be between 10am and 4pm. However, there is some research that indicates the best time to reap optimal Vitamin D levels from the sun is noon or between 10am and 1pm. To do this, you don’t need a lot of time to soak up the Vitamin D. Anywhere from 5 to 10 minutes  – without sunscreen – during peak times should do. Sunscreen blocks the sun’s rays, so when you are trying to optimize your Vitamin D levels during those 5-10 minutes it’s best not to wear it.

Conventional sunscreens contain many chemicals that disrupt the endocrine system, irritate the skin and are carcinogenic. If you’re going to be in the sun for awhile, choose non-toxic options such as mineral sunscreens and cover up as much as possible, either with clothing or shade, to protect yourself from too much sun exposure.

Instead of fearing the sun, let’s appreciate its incredible health benefits and enjoy it wisely.