​The Science-Backed Health Benefits Of Sunlight + Vitamin D

​The Health Benefits of Summertime

1. Sunlight cheers you up
Shorter, darker fall and winter days can lead to SAD or seasonal affective disorder, (1) a condition that affects about 6 percent of people severely, causing depression, and about 20 percent more mildly. SAD is four times more common in women, but fortunately it is alleviated by longer, sunnier days, come spring and summer. One mechanism for this is the brain’s ability to produce (2) more serotonin, that feel-good neurotransmitter, with increased exposure to sunlight. Full-spectrum lights can treat SAD during wintertime – ask your doctor about getting a prescription for these lights.
2. Seasonal food boosts your mood
All the best fruits and vegetables are fresh, ripe, and ready to eat during the warmer months and are much more likely to be available locally, through farmers markets and local farms or your very own backyard or porch garden. That means people tend to eat more produce in the summer, and therefore get more vitamins, minerals, and other phytonutrients that boost immune function and mood.
3. The sunshine vitamin feeds your brain
When your skin is exposed to sun, it starts synthesizing good ol’ vitamin D, the sunshine vitamin, which is responsible for the proper workings of hundreds of different pathways that control your mood, immune system, and brain function. Every single cell of your body needs vitamin D to do its best work, and there is no better time to bask in that vitamin producing sunshine than in the summer.
4. Nature calls
Nature heals, and that’s a fact. When it’s cold, people spend more time inside – another fact. But nature calls, and when you answer that call, you will feel better. One study published in the Proceedings of the National Academy of Sciences, demonstrated that when a group of people walked for 90 minutes in nature they reported fewer negative thoughts compared to the group who walked in the city. Functional MRI brain scans also revealed that the nature walkers had less activity in the subgenual prefrontal cortex, an area of the brain that plays a role in mood disorders and negative thoughts than the city walkers. So city folk, look for a park!
5. Fresh air fights viruses
Poorly ventilated rooms are more likely to foster (3) the cold virus, which also tends to spread more (4) during colder months. Other studies from the NIH found that the flu virus actually became tougher (5) during winter.
6. More sun means better sleep
The presence and absence of sunlight talks to your brain’s pineal gland, telling it to slow down the production of that sleepy-time hormone melatonin when it’s light, and increase production when it’s dark. When the dark hours are longer, and you are outside in the sunlight less often, it can be harder to wake up in the morning, and you may feel sleepier during the day. This can also leave you with less melatonin production at night, reducing sleep quality because your pineal gland isn’t getting those natural signals.
7. Genes adjust to the seasons
About 25% of your DNA actually changes with the seasons, according to one fascinating study (6) published in the scientific journal Nature. The study found that during the winter months, DNA changes seemed to be geared toward preparing for increased exposure to viruses. In the summer, different sets of genes were turned on that were more geared toward blood sugar balance, perhaps in anticipation of all that delicious summer produce. This summer change helps calm cravings and burn off winter fat, too.
8. Sun chills out over-reactive immune responses
Sunlight is sometimes used to treat auotimmune diseases of the skin, like psoriasis, because sun exposure can actually help suppress an overactive immune system. This may be because sun exposure increases white blood cells, which help fight disease and defend the body against infection.
Since you can’t stop winter from coming, does all this summer awesomeness mean you should move to a warm climate for an everlasting summer? Don’t get that one-way ticket to the tropics just yet. One study found that people were no happier in southern California than in the cold, cloudy, snowy, rainy Midwest, even though Midwesterners complained more about the weather.

Other studies point to the fact that while suicide rates are higher in the Arctic circle, they are actually even higher in warmer South Korea than in icy Scandinavian countries. Speaking of Scandinavians, they are listed as some of the happiest people in the world, despite their gloomy cold weather, comparatively. Must be all the hygge. Another factor may be the genetics of different populations, which could impact such biochemical functions as vitamin D metabolism. Another thing to consider is the diet of very happy people who live in colder, cloudier parts of the world, as traditional diets consist of a lot of wild-caught fatty fish – rich in vitamin D.
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So do the seasons play a role in your mood, energy, and health? Absolutely, but they are far from the only factor, and are not nearly as important as dietary choices, activity level, family and social bonds, and attitude.

How can you BOOST your Vitamin D

​Sometimes our lives get so busy that we forget to appreciate the wonders of the body and everything it allows us to do. You have 60,000 miles of blood vessels running through your body, and you produce 25 million new cells each second!
And while your trillions of cells all have their own purpose, they also have one thing in common: They all need vitamin D.

The sunshine vitamin
Vitamin D is known as the sunshine vitamin because our awesome bodies manufacture it when sunlight hits our skin. Your body absorbs sunlight using cholesterol, which helps convert sunlight into a form of vitamin D that your body can use. Sunlight is life to your body. And you might not guess it from its name, but vitamin D is actually more like a hormone than a vitamin. It helps to regulate hundreds of different pathways in your body. It is so important that vitamin D and your thyroid hormones are the only two hormones every cell needs, making them the king and queen of all hormones, and essential for good health including:

1. Fights depression
Have you ever noticed how sitting in the sun makes you feel good? The vitamin D activated by that sun exposure acts as an antidepressant in your system, which makes sense when you consider how many people get the “winter blues” coinciding with decreasing amounts of sunshine during the colder months. Low levels of vitamin D are linked to a 14 percent increase in depression and a 50 percent increase (7) in suicide rates! That makes this sunshine vitamin pretty essential!

2. Reduces asthma
Studies show (8) that pregnant moms with higher vitamin D intake give birth to babies with a 40 percent reduced risk of developing asthma. Other research suggests (9) that vitamin D has a protective effect against upper-respiratory infections in adults.

3. Balances immunity
Vitamin D is an integral part of your immune system, so it’s no surprise that low levels of vitamin D are associated with autoimmune conditions such as MS, (10) Parkinson’s, (11) type 1 diabetes, (12) inflammatory bowel disorders, (13) and autoimmune thyroid problems (like Hashimoto’s disease (14) and rheumatoid arthritis). (15) Conversely, optimal levels are linked with symptom improvement.

4. Strengthens bones
Just in case you haven’t heard, vitamin D prevents (16) the breakdown of bone and increases the strength of the skeletal system.

5. Boosts brain power
Vitamin D is essential for a healthy brain, and low levels of D are linked (17) to decreased memory and increased rates (18) of neurological conditions like Alzheimer’s.

6. Fights cancer
People who have optimal vitamin D levels have lower levels of breast, (19) prostate, (20) colon, (21) ovarian, (22) and pancreatic (23) cancer. There is also some evidence that this vitamin can both kill cancer cells and impede their growth by up to 50 percent!

7. Improves fertility
Healthy vitamin D levels have been shown to increase the health (24) of sperm and increase (25) healthy pregnancy rates.

8. Protects the heart
Low D levels and decreased exposure to sunlight are associated (26) with more occurrences (27) of heart attacks and strokes.

9. Calms inflammation
Inflammation is the common link between most chronic health problems, and vitamin D is an essential part of the body’s capability (28) to squelch the inflammatory storm going on.

10. Revs up metabolism
In one study, (29) supplementing with D for 12 weeks decreased body fat by 7 percent. Low levels are also linked (30) to metabolic syndrome, which is a precursor to type 2 diabetes.

11. Enhances physical performance
Supplementing with this important vitamin has been shown to boost muscle strength and physical performance. Vitamin D has also been shown in some studies to increase balance, (31) decreasing falls by 20 percent.

12. Improves sleep
Sleep is so important for feeling and looking your best, and healthy levels of D are associated with (32) better sleep quality.

Ok, vitamin D is super important; so what can I do about it?