Join the Loyalty Program for Discounts

The Silent Disease of Vitamin D Deficiency

Article at-a-glance:

  • Vitamin D deficiency is a serious health threat that needs to be on everyone’s radar.
  • Vitamin D regulates the functions of more than 200 genes and is one of the most important molecules for our health.
  • Vitamin D is so important to health that a 2008 study found low blood levels were associated with double the risk of death overall.

by Dr. John Neustadt

Vitamin D regulates the functions of more than 200 genes and is one of the most important molecules for our health—so important that the human body produces its own supply daily from the ultraviolet B (UVB) spectrum of sunlight.1 And yet vitamin D deficiency is rampant in children and adults alike.2,3 According to two studies that evaluated vitamin D levels in 11,000 people, about 40% of adults and 70% of children are deficient in this crucial nutrient.4,5 People with malabsorption issues, such as Crohns disease, Ulcerative Colitis and Celiac, and the elderly have even higher risks for vitamin D deficiency.

Since vitamin D affects so many genes, it’s not surprising that vitamin D helps protect us from a whole host of problems. Vitamin D can help us fight infections; help protect against diabetes, heart disease, cancer, asthma, depression, autoimmune diseases like multiple sclerosis (MS) and rheumatoid arthritis (RA); and generally boosts your immune system. Vitamin D increases our absorption of critical vitamins and minerals, including calcium and magnesium. Strong, healthy bones depend on vitamin D. Unfortunately, deficiency of vitamin D is often a “silent disease” with very few obvious symptoms. 

Why Low Vitamin D is So Common

There are several reasons that can explain why so many people are deficient in vitamin D. These days we just don’t get enough steady sunlight, and when we do, we’re either covered up or we slather ourselves with sunblock, preventing UVB from penetrating our skin. To prevent Vitamin D deficiency, it takes fifteen to twenty minutes of sunshine daily with more than 40% of your skin exposed.6

If you live in the northern hemisphere above 37 degrees north latitude, in the winter the sun never gets high enough to stimulate our own vitamin D production.7 

Where exactly is that? Thirty-seven degrees is an imaginary line that passes through California (near Santa Cruz), Nevada, southern Utah, northern Arizona, along the Colorado/New Mexico border, and through the Kansas/Oklahoma border, Missouri, southern Illinois, Kentucky and Virginia. So if you live in those areas, or north of them, in the winter your risk for vitamin D deficiency is higher than your neighbors to the south.

Darker skin, which contains relatively more melanin than lighter skin, slows the production of vitamin D. Similarly, aging reduces skin vitamin D production. Common glass in home or car windows and clothing all reduce UVB radiation exposure, even in summer months.

One Powerful Nutrient

Vitamin D deficiency is a serious health threat that needs to be on everyone’s radar. Vitamin D deficiency not only causes rickets among children but also osteoporosis among adults and causes the painful bone disease osteomalacia. Vitamin D deficiency has been associated with increased risks of deadly cancers, cardiovascular disease, multiple sclerosis, depression, schizophrenia, rheumatoid arthritis, and type 1 diabetes mellitus.8,9

Inflammation and Autoimmune Diseases

Studies show that vitamin D helps render the immune system more tolerant and less reactive, reducing the levels of pro-inflammatory molecules produced by immune cells. Since inflammation fuels the “fire” of autoimmune disease, vitamin D can be helpful.10 

Clear connections can be seen between vitamin D deficiency and numerous autoimmune disorders like multiple sclerosis, Crohn’s disease and diabetes.11,12 A review of ten studies on vitamin D found that the vitamin improves insulin resistance and lowers the risk of diabetes.13

In those who suffer from Crohn’s disease, it has long been recognized that vitamin D deficiency is likely because of malabsorption, but more recently studies have suggested that deficiency can contribute to the disease and that supplementation is beneficial. A study in 2016 of 94 Crohn’s patients who were in remission found that vitamin D supplementation slashed the relapse rate; a second study found that “leaky gut” was improved in those who took vitamin D.14  Vitamin D has also been found beneficial in multiple sclerosis in Caucasians—a study of 148 MS patients and 296 healthy individuals found that the risk of MS significantly decreased as levels of vitamin D increased.15


Research indicates vitamin D deficiency has been associated with increased risk for dying from cancers, including breast, uterine, prostate and colon cancers, as well as for getting heart disease, stroke, autoimmune diseases, birth defects, periodontal disease and infections.16,17

Vitamin D is so important to health that a 2008 study found low blood levels were associated with double the risk of death overall.18 This trend was confirmed by a larger study that showed a significant reduction in cancer mortality with vitamin D3 supplementation.19 

Healthy Mood

Globally, it’s estimated that 350 million people suffer from depression.20 While depression is a complex condition with many potential causes, including low iron, low testosterone and poor sleep, supplementation with vitamin D has been found beneficial for those who have a diagnosis of clinical depression.21 A 2013 study found more than twice the risk of depression in those with low vitamin D levels compared to the general population.22 Mood can be boosted as well by supplementing with vitamin D in those with fibromyalgia, diabetes, obesity or even simply old age.23-25  

Heart Health

Low vitamin D is linked to heart disease. Vitamin D deficiency has been linked to vascular dysfunction; arterial stiffening; hypertension, and high cholesterol—as well as a greater risk of cardiovascular problems and death.26 Coronary artery disease to heart attack, heart failure, atherosclerosis and hypertension are linked to vitamin D deficiency.27,28 Research shows that vitamin D plays a critical role in preserving and even restoring the function of the endothelium—the protective inner lining of our blood vessels, from our largest artery to our smallest capillary.29

Bone Health and Fractures

When most people think about an osteoporosis dietary supplement they right away think of calcium and vitamin D. In fact, the FDA has approved calcium and vitamin D to “reduce osteoporosis risk.” The most dangerous risk with osteoporosis is fracturing a bone. Fortunately, adequate levels of vitamin D are associated with increased bone mineral density and a reduced risk of bone fracture, especially as we age.30 

Several studies have evaluated how powerful vitamin D and calcium are for reducing fractures. One study found a modest 16% reduction in fracture risk over 3 years in 2532 community-dwelling residents (average age, 73 years; 59.8% female) who supplemented with 400 IU vitamin D3 and 1000 mg calcium daily.29

Vitamin D Testing and Optimal Levels

Far too many of my patients suffered from low vitamin D levels, but most didn’t realize their vitamin D was low. Because I know how crucial this vitamin is to optimal health, testing vitamin D was commonly done in my clinical practice. Vitamin D testing is as easy as a simple blood draw, often available alongside other routine blood work or testing. 

Oral supplementation of 2,000-5,000 IU/day (50-125 micrograms per day) is generally well-tolerated.31 In 2011 the Institute of Medicine suggested the level needed for good bone health for most individuals is 20 nanograms per mL (ng/mL).32

However, other researchers have concluded that higher levels are even better. To reduce the risks for falls and fractures, a person’s Vitamin D blood concentration should be 30-44 ng/mL. Above 30 ng/mL, nonvertebral fractures decrease by 20% and hip fractures by 18%. Similarly, the greatest decrease in the risk for falling is seen when someone’s vitamin D level is about 30 ng/mL, and dying from any cause was reduced when the blood level was 40-48 ng/mL.33

If You Liked This, You May Also Enjoy

Vitamin K and Fractures

Tired? Breathless? RLS? Iron Deficiency Might be the Cause

What’s in Your Milk? Top Reasons to Rethink Dairy


1Naeem Z. Vitamin d deficiency- an ignored epidemic. Int J Health Sci (Qassim). 2010;4(1):V-VI. 

2Wilson LR, Tripkovic L, Hart KH, et al. Vitamin D deficiency as a public health issue: using vitamin D 2 or vitamin D 3 in future fortification strategies. Proceedings of the Nutrition Society. 2017 Aug;76(3):392-9.

3Holick MF. The vitamin D deficiency pandemic: approaches for diagnosis, treatment and prevention. Reviews in Endocrine and Metabolic Disorders. 2017 Jun 1;18(2):153-65. 

4Parva NR, Tadepalli S, Singh P et al. Prevalence of vitamin D deficiency and associated risk factors in the US population (2011-2012). Cureus. 2018 Jun 5;10(6):e2741. 

5Melamed ML, Kumar J, Muntner P et al. Prevalence and associations of 25-Hydroxyvitamin D deficiency in children and adolescents in the United States: Results from NHANES 2001-2004. Pediatrics, 2009 Sep;124(3):e362-70 

6Naeem Z. Vitamin d deficiency- an ignored epidemic. Int J Health Sci (Qassim). 2010;4(1):V-VI. 

7Time for more vitamin D. Harvard Women’s Health Watch.  September 2008.

8Holick MF. Vitamin D: importance in the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis. Am J Clin Nutr. 2004;79(3):362-371.

9Holick MF. Vitamin D Deficiency. N Engl J Med. 2007;357(3):266-281.

10Prietl B, Treiber G, Pieber TR, et al. Vitamin D and immune function. Nutrients. 2013 Jul 5;5(7):2502–21. 

11Vanherwegen A-S, Gysemans C, Mathieu C. Regulation of immune function by vitamin D and its uses in immunity. Endocrinol Metab Clin North Am. 2017 Dec;46(4):1061–94.

12Munger KL, Levin LI, Hollis BW, et al. Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis. JAMA. 2006 Dec 20;296(23):2832–8.

13Effect of vitamin D supplementation on insulin resistance and glycaemic control in prediabetes: a systematic review and meta-analysis. Diabet Med. 2016 Mar;33(3):290-9.

14White JH. Vitamin D deficiency and the pathogenesis of Crohn’s disease. J Steroid Biochem Mol Biol. 2018 Jan;175:23–8. 

15Munger KL, Levin LI, Hollis BW. Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis JAMA. 2006 Dec 20;296(23):2832-8.

16Calvo MS, Whiting SJ, Barton CN. Vitamin D intake: a global perspective of current status. J Nutr. 2005;135(2):310-316.

17Zhang R, Naughton DP. Vitamin D in health and disease: current perspectives. Nutr J. 2010;9:65.

18Melamed ML et al. 25-hydroxyvitamin D levels and the risk of mortality in the general population. Arch Intern Med. 2008 Aug 11;168(15):1629-37. 

19Bjelakovic G, Gluud LL, Nikolova D, et al. Vitamin D supplementation for prevention of mortality in adults. Cochrane database of systematic reviews. 2014(1).

20World Health Organization [WHO], DEPRESSION: A Global Crisis World Mental Health Day, October 10 2012.

21Shaffer JA, Edmondson D, Wasson LT, et al. Vitamin D supplementation for depressive symptoms: a systematic review and meta-analysis of randomized controlled trials. Psychosom Med. 2014 Apr;76(3):190–6.

22Anglin RES, Samaan Z, Walter SD, et al. Vitamin D deficiency and depression in adults: systematic review and meta-analysis. Br J Psychiatry. 2013 Feb;202:100–7.

23Armstrong DJ, Meenagh GK, Bickle I, et al. Vitamin D deficiency is associated with anxiety and depression in fibromyalgia. Clin Rheumatol. 2007 Apr;26(4):551–4. 

24Jorde R, Sneve M, Figenschau Y, et al. Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial. J Intern Med. 2008 Dec;264(6):599–609. 

25Okereke OI, Singh A. The role of vitamin D in the prevention of late-life depression. J Affect Disord. 2016 Jul 1;198:1–14. 

26Mheid IA, Quyyumi AA. Vitamin D and cardiovascular disease. State-of-the-Art-Review. Journal of the American College of Cardiology 2017 (70):1: 89-100.

27Rai V et al. Role of vitamin D in cardiovascular diseases.Endocrinol Metab Clin North Am. 2017 Dec;46(4):1039-1059.

28Brinkley DM, Ali OM, Zalawadiya SK et al. Vitamin D and heart failure. Curr Heart Fail Rep. 2017 Oct;14(5):410-420.

29Khan A, Dawoud H, Malinski T. Nanomedical studies of the restoration of nitric oxide/peroxynitrite balance in dysfunctional endothelium by 1,25-dihydroxy vitamin D3 – clinical implications for cardiovascular diseases.Int J Nanomedicine. 2018 Jan 19;13:455-466.

30Cranney A, Horsley T, O’Donnell S, et al. Effectiveness and safety of vitamin D in relation to bone health. Evid Rep Technol Assess . 2007 Aug;(158):1–235.

31Tayem Y, Alotaibi R, Hozayen R, et al. Therapeutic regimens for vitamin D deficiency in postmenopausal women: a systematic review. Przeglad menopauzalny= Menopause review. 2019 Apr;18(1):57.

32AAFP. IOM Updates Guidance on Vitamin D, Calcium. 2010.

33Bischoff-Ferrari HA, Shao A, Dawson-Hughes B, Hathcock J, Giovannucci E, Willett WC. Benefit-risk assessment of vitamin D supplementation. Osteoporos Int. Jul 2010;21(7):1121-32.

3-Steps to Eating Healthy for Life

3-Steps to Eating Healthy for Life

People often ask me what my diet is like. How I and my family eat. In my clinical practice and lecturing, I’ve helped thousands of people learn my simple system for revamping their eating to a dietary pattern that promotes health. With every bite of food, you’re...

Top Adaptogenic and Calming Herbs for Sleep

Top Adaptogenic and Calming Herbs for Sleep

Article at-a-glance: Healthy sleep is crucial for healthy memory, energy, mood, healthy blood sugar, blood pressue and much more.  Supporting healthy sleep is directly related to our ability to handle stress The body’s innate stress response system, the hypothalamic...

Share This