At a glance

The Vitamin D Deficit: An average of 41% of American adults are Vitamin D deficient.
Benefits of Vitamin D: Immune Response, Heart Health, Bone Strength & more.
Vitamin D Dosing: How much is right for you?
The Sources of Vitamin D: Is sunshine enough?

When you think of Vitamin D, what is the first thing you associate it with? You’re certainly not alone if you thought of the sun. After all, Vitamin D is commonly referred to as the “sunshine vitamin” because it is produced in your skin in response to sunlight exposure. And while our skin is constantly exposed to sunlight, our eyes, ears, and brain are also exposed to the many marketing campaigns for Vitamin D, with their sunny backdrops complete with warm and inviting colors.

Although sunlight is a major source of Vitamin D, there are alternative sources, including food and dietary supplements that can help you meet your Vitamin D needs as well. This is important because an average of 41% of American adults are Vitamin D deficient, with that number soaring upwards to over 82% for some ethnicities and ages.

A common misconception among both children and adults is they believe they can receive enough Vitamin D through sunlight exposure. While sunlight does allow the skin to produce Vitamin D, it is only part of the solution. And that is particularly true during winter – especially in Northern regions – or if you spend most of your day indoors. In fact, as we’ll discuss further below, Vitamin D deficiency is so prevalent that it constitutes a public health crisis.

When consumed at the proper dosage, Vitamin D promotes immune system response, heart health, bone strength, joint function, and even brain health and a positive mood. This is why it is important to diversify your sources of Vitamin D and make sure you nourish your body with enough of this essential daily vitamin.

With all of that in mind, let’s discuss the full range of clinically studied benefits Vitamin D has to offer.

Vitamin D Benefits

Immune System Response

As mentioned, your body produces Vitamin D using an adequate amount of sun exposure. The vitamin — which is really a hormone — is subsequently disbursed to various areas throughout your body including your immune system. From here, Vitamin D alters the production of antimicrobial peptides, especially cathelicidin. These small peptides demonstrate a broad spectrum of antimicrobial activity against bacteria and are capable of triggering specific defense responses as well.

According to one study, the connection between Vitamin D and cathelicidin has evolved over millions of years to efficiently promote healthy immune systems. The study stressed the importance of Vitamin D and its ability to regulate anti-bacterial proteins like cathelicidin.

So, what does this mean for immune health?

Research has demonstrated the importance of Vitamin D for immune system health. The study mentioned above credits cathelicidin as being more than just a regulator of microbes — it also prompts your body to activate the immune system when harmful invaders are present.

Heart Health

As we age, it is important to support your heart with the proper vitamins, minerals, and nutrients. Although the proper nourishment for your heart is required at any age, its importance becomes magnified with each passing year.

According to the American Heart Association, 67 percent of adults between 60-79 years of age are impacted by cardiovascular disease. Once you hit 80, that number balloons to roughly 84 percent. Therefore, it becomes increasingly important to take care of your heart with age, and now is the right time to start.

Multiple studies show a correlation between Vitamin D deficiency and heart trouble. One notable study from 2014 analyzed data gathered from nearly 150,000 people in Europe and North America. The findings suggest that as Vitamin D levels increase, the odds of developing high blood pressure decrease. And that is just the beginning of the evidence for keeping your Vitamin D levels up to protect your heart. More and more studies are being undertaken to examine the role Vitamin D can play in cardiovascular health.

Bone Strength

Nutrients, a peer-reviewed scientific journal, published an article entitled “Vitamin D and Bone Health; Potential Mechanisms” to highlight how Vitamin D positively impacts bone health. This analysis stressed the importance of Vitamin D and made it clear that it is essential for bone health. They went on to summarize that without insufficient Vitamin D intake could lead to increased bone metabolism destabilization and increased risk of bone fracture.

The need for adequate supplementation of Vitamin D increase with age according to Nutrients. Although genetics, physical activity, nutrition, and lifestyle factors all impact our bone health, the average person obtains peak bone mass by the third decade of life. However, age-related bone loss occurs just 10 years after from peak bone mass, making Vitamin D all the more important. Sadly, this trend continues on with age and could lead to weakened bones and an increase in fracture risk. On top of its impact on bone mass and bone mineral density, research suggests that Vitamin D enhances muscle function, which leads to a decreased number of falls among the elderly.

The findings in this analysis clearly indicate the importance of Vitamin D when it comes to bone health.

Joint Function

Joint health is another area to focus on as we age. And while Vitamin D is not really thought of as a joint nutrient, researchers found that being deficient in Vitamin D could lead to discomfort in your knees and hips. This particular clinical study monitored adults aged 50-80 years over the course of 5 years using linear regression while taking age, gender, body mass, and season into consideration. Further adjustments were made for discrepancies in bone structure including radiographic osteoarthrosis, bone marrow lesions, defects, and muscle strength.

The results of the study showed that Vitamin D deficiency worsened knee pain over 5 years and intensified hip pain in half the amount of time.

Brain Health and Positive Mood

Two additional benefits of Vitamin D to keep tabs on are brain health and mood. A great deal of emerging research has elevated Vitamin D into the conversation for its role in cognitive function and daily mental outlook. For example, a recent analysis of low Vitamin D and its association with cognitive impairment examined the vitamin’s anti-inflammatory, antioxidant, and neuro-protective properties and the role it plays in brain health. The investigation notes that Vitamin D increases neurotropic factors that promote brain health.

Evidence from cellular studies suggest that Vitamin D is present throughout our central nervous system and could be involved in future approaches to brain disorders. Furthermore, the 2020 investigation cited multiple cross-sectional and cross-control studies as confirmation that low Vitamin D levels are associated with increased risk of cognitive decline.

Clinical studies continue to make strides with Vitamin D and its association with brain health and have helped the vitamin trend in the right direction.

As for Vitamin D and its role in promoting a positive mood, research has shown the sunshine vitamin to be a potential key factor in regulating mood in obese and overweight individuals. A randomized, double blind trial published in the Journal of Internal Medicine tested 441 obese subjects aged 21-70 years at the University Hospital of North Norway.

The results indicated that subjects with greater Vitamin D supplementation “scored significantly higher” than those who received a smaller dosage. Consequently, it appeared that supplementation of Vitamin D improved the mood in subjects. Further study hopes to yield the same conclusions for the wider population.

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How Much Vitamin D Should You Take?

Vitamin D deficiency is one of the most common nutrient deficiencies, as over 40% of the U.S. population falls into this category. And like other vitamins and minerals, the recommended intake of Vitamin D varies by individual. Therefore, it is extremely important to familiarize oneself with recommended intakes.

Back in 2003, Dr. John Cannell founded the Vitamin D Council to educate the public about this critical deficiency. Although his goal was to inform the public on Vitamin D, sun exposure, and general wellbeing, many Americans thought they were already getting enough of the sunshine vitamin and were hesitant to take dietary supplements that appeared to contain heavy doses. However, scientific evidence, including this 2007 clinical review, has debunked this school of thought. In fact, someone standing in the midday summer sun would make about 10,000 IU of vitamin D in about an hour. No one has been diagnosed with Vitamin D poisoning from spending just one hour in the sun, so fears of overdosing have cooled down.

And really, who is sitting in the sun for an hour… That is, unless they have slathered on the recommended sunscreen. And while sunscreen is very important for skin health and protection, it does cancel out the UV light required to spur Vitamin D synthesis. So, you can see how getting enough Vitamin D solely from the sun could be difficult — even more so for the office worker or people in less sunny climes, especially during the winter.

Dr. Cannell went on to state that supplementing with 5,000 IU of Vitamin D per day would help move people towards a more sufficient Vitamin D level. According to Dr. Cannell, “The Vitamin D Council arrived at this recommendation very simply {as a way} to reproduce natural vitamin D from sun exposure. We know that natural vitamin D levels for lifeguards and roofers and hunter-gatherers from modern-day Tanzania are about 50 ng/mL. Until all the studies are done and all the science is completed, the safest thing for you to do is to maintain a natural vitamin D level.”

Although it is quite difficult to consume an excess amount of Vitamin D, it is still important to find a healthy balance. However, this blog is for informational use only. We advise you to consult with your doctor or other medical professional to determine the right amount of Vitamin D to consume per day.

Sources of The Sunshine Vitamin

As discussed, our bodies use sunlight to produce Vitamin D. According to Healthline, sun exposure is the best way to boost Vitamin D levels. Simply put, your skin produces Vitamin D from cholesterol when exposed to sunlight. This process is kickstarted once the ultraviolet B rays from the sun reach the cholesterol in your skin cells. In turn, this provides enough energy for Vitamin D synthesis to occur.

Midday, especially during the summer months, is the best time to soak in sunlight, according to Healthline. But you may question whether the risk of getting too much sun outweighs the reward in the form of Vitamin D — and you wouldn’t be alone. A 2010 study published in the Journey of Investigative Dermatology examined the recommendations on limitation of sunlight exposure to prevent skin issues and how it may conflict with requirements to promote health through adequate Vitamin D levels.

A key takeaway from this study is that the sun is at its highest point at noon. Its UVB rays are most intense at this stage of the day, which means your body requires less time in the sun to produce a sufficient amount of Vitamin D. As always, remember to perform this activity in a responsible manner and use plenty of sunscreen, remain hydrated, and utilize shady areas.

However, you can nourish your body with plenty of nutritious sources of Vitamin D without having to step outside (not that we advocate staying inside all the time — we are big outdoor buffs). The U.S. Department of Health and Human Services published a list of foods containing Vitamin D. Seafood took the top three spots on the list, as 1 tablespoon of cod liver oil contains 1,360 IU per serving, while 3 ounces of cooked trout yields 645 IU of Vitamin D. Plus, a 3 ounce serving of cooked salmon has 570 IU of Vitamin D. For those who prefer other options, you can’t go wrong with the 366 IU of Vitamin D found in one ½ cup of sliced mushrooms.

Although seafood dominates the top of the list, sources of dairy are scattered throughout as well. For instance, 1 cup of 2% milk contains 120 IU per serving, but 1 ounce of cheddar cheese has just 12 IU of Vitamin D.

Even the top options on this list aren’t exactly loaded with Vitamin D. That is why supplementing with Vitamin D — either in specialty formulas or a daily multivitamin — may serve as your best bet.

Sunsetting Thoughts On Vitamin D

Vitamin D intake is most closely associated with sun exposure. Although the sun is strongest in the summer, that doesn’t mean you should stop seeking an adequate amount of Vitamin D in the form of food and dietary supplements every day to support your immune system response, heart, bones, joint, and brain. So, be sure to consume plenty of the sunshine vitamin all year long!

References

https://pubmed.ncbi.nlm.nih.gov/21310306/

https://www.hsph.harvard.edu/nutritionsource/vitamin-d/

https://www.heart.org/idc/groups/heart-public/@wcm/@sop/@smd/documents/downloadable/ucm_483970.pdf

https://www.healthline.com/nutrition/vitamin-d-from-sun#skin-color

https://www.jpmph.org/journal/view.php?doi=10.3961/jpmph.16.111

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2821804/

https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/

https://pubmed.ncbi.nlm.nih.gov/18290725/

https://pubmed.ncbi.nlm.nih.gov/20072137/

https://pubmed.ncbi.nlm.nih.gov/21310306/

https://pubmed.ncbi.nlm.nih.gov/23595144/