Research underscoring the importance of vitamin D continues to mount. Vitamin D was long thought to be beneficial for mainly bone health, but it turns out it’s helpful for so much more. It’s strikingly clear that vitamin D, one of the most misunderstood nutrients, offers hundreds of benefits to human health, and many of those benefits have yet to be discovered. It’s so beneficial that even mandatory fortification of food with vitamin D is beginning to see some serious discussion in Europe. With healthcare costs rising worldwide, could adding such a necessary (and inexpensive) nutrient be helpful? Many experts believe so, but it comes down to the quality of the fortification that will make sense and will provide the most benefit.
Vitamin D Deficiency is More Concerning Than You Think
An estimated 75% of people have insufficient levels of serum vitamin D, and this number is probably far more than generous.  Vitamin D is responsible for over a hundred biological processes, including regulating immune system status, modulating proper blood sugar, supporting memory and overall mental health, keeping metabolism in check, and much more. It’s clear that a vitamin D deficiency is contributing to the spiraling costs of medications, possible preventative medical procedures, and various therapies. Europe is slowly but surely coming around to the idea of using fortification programs to help fight vitamin D deficiency. The question is: are health officials going to use the appropriate form of vitamin D?
Finland adopted a vitamin D fortification program in 2003-2004 that expanded on fortified dairy products. Most developed countries have vitamin D added to milk, but some countries, like Finland and Sweden, are fortifying oils, packaged foods, and beverages. The issue with nutrient fortification programs is the quality of the nutrient used. For most dairy products, vitamin D3–the quality of which may be questionable–is used. D3 is the form that actually has a beneficial effect on serum levels, whereas vitamin D2 is lower quality synthetic and not as useful.  Some dairy-free milk alternatives only include D2, offering no real benefit.
Vitamin D Deficiency Symptoms
Some of the most common symptoms of vitamin D deficiency are bone pain and muscle weakness, but these symptoms can go undetected in the initial stages. 
In adults Vitamin D deficiency can lead to osteoporosis, a condition that makes your bones weak and more and more prone to break. In children, this deficiency can cause rickets, a disorder that leads to softening of and weakening of the bones.
Who’s at Risk of Vitamin D Deficiency?
- Older adults
- People with limited sun exposure
- People with dark skin
- People suffering from inflammatory bowel disease (IBD)
- People who are obese 
Benefits of Vitamin D
To fully understand the impact vitamin D deficiency can have on your health, you need to know about the many benefits vitamin D holds for the body. Did you know without proper vitamin D levels, for example, you could raise the risk for dementia?  There are many surprising benefits of vitamin D, and according to Harvard School of Public Health, vitamin D provides these benefits :
- Blood sugar support
- Bone health
- Immune system support
- Cardiovascular health
- Cholesterol support
Vitamin D may also be helpful for supporting a healthy mood and for regulating sleep patterns. When you shun the sun, whether intentionally or not, you’re setting yourself up for a host of issues. Balancing levels by getting out in the sun or supplementing could be helpful for getting your health back on track.
SEE also Vitamin D Medicine
The Best Type of Vitamin D
One of the simplest interventions you can take right now in your own health is simply stepping outside. The sun supports all life on this planet, and it’s available–free of charge–for you to take advantage of its rays. While you should certainly take precautions to protect your skin from overexposure to sunlight (particularly the face), getting a few minutes’ worth of sun exposure on as much as your skin as possible can be the best bet for producing vitamin D. Depending on your current vitamin D status, you may have to spend more or less time out in the sun compared to the next person.
For the autumn and winter months, sunlight exposure can be a bit more tricky. That’s when supplementation comes in, but it’s important to choose one that is vegan friendly, as many vitamin D3 supplements are produced from sheep wool. Although some foods do contain vitamin D, such as egg yolks and cod liver oil, it’s not a reliable source for those who are severely deficient. Before supplementing with vitamin D, work with a knowledgeable medical practitioner who can test your levels and guide you toward the correct supplementation pattern.
- Adit A. Ginde, MD, MPH; Mark C. Liu, MD; Carlos A. Camargo Jr, MD, DrPH. Demographic Differences and Trends of Vitamin D Insufficiency in the US Population, 1988-2004. Arch Intern Med. 2009;169(6):626-623. doi:10.1001/archinternmed.2008.604.
- Lisa A. Houghton and Reinhold Vieth. The case against ergocalciferol (vitamin D2) as a vitamin supplement. Am J Clin Nutr October 2006 vol. 84 no. 4 694-697.
- “Vitamin D — Health Professional Fact Sheet.” National Institute of Health. 2015. 1 Jun. 2016.
- Cynthia Balion, PhD, Lauren E. Griffith, PhD, Lisa Strifler, BSc, et al. Vitamin D, cognition, and dementia: A systematic review and meta-analysis. Neurology. 2012 Sep 25; 79(13): 1397-1405. doi: 10.1212/WNL.-b-13e31826c197f.
- Harvard T.H. Chan. School of Public Health Vitamin D and Health. Harvard T.H. Chan. School of Public Health. The Nutrition Source.