Vitamin D Deficiency: Symptoms, Causes, and Treatment

Do you know what’s at risk if you suffer from vitamin D deficiency? The “sunshine vitamin”, also known as calciferol, is essential for keeping our bones strong by helping us absorb calcium. It’s not just fundamental for the skeletal system, though – you also need it for healthy teeth and a strong immune system.

If you need more reasons to care about your vitamin D levels, there are plenty. Low vitamin D can impact your muscles – and the worst part is that vitamin D deficiency symptoms are hard to notice. That’s why we’re going to delve into the signs of vitamin D deficiency, what causes it, and how we can prevent or treat it.

Key Ideas

  • Your body can obtain vitamin D through sunlight, food, and dietary supplements. Even so, most of the population doesn’t get enough of this nutrient, which is fundamental to bone health.
  • Vitamin D deficiency is not always easy to diagnose, as the symptoms are rather non-specific. However, if you don’t spend much time in the sun and you don’t include oily fish in your diet, it’s completely plausible that you may have low vitamin D.
  • Supplements with liposomal formulas have been proven effective at providing the body adequate doses of vitamin D. They’re scientifically validated; once you try them out, you won’t want to go back!

Vitamin D Deficiency: What You Need to Know

You probably already know that when your skin is exposed to sunlight, it produces vitamin D. So is it enough to hit the beach during the summer? No! You should be getting sunlight every day of the year, though you can also obtain this nutrient through food. Better yet are supplements which securely prevent health problems. Let’s look at some questions you may have about this crucial vitamin.

girl on the beach
Your body can obtain vitamin D through sunlight, food, and dietary supplements. (Source: Jackson: v53qmbo25fs/ Unsplash.com)

What Are the Symptoms of Vitamin D Deficiency?

Often, low vitamin D levels don’t cause symptoms. In other cases, vitamin D deficiency can manifest in highly non-specific ways. In other words, it can be confused with other conditions like fibromyalgia, chronic fatigue syndrome, or even normal aging. Let’s look at some example symptoms:

  • Bone and joint pain
  • Exhaustion
  • Physical weakness
  • Muscle cramps
  • Headaches

The real problem with low vitamin D doesn’t lie with these symptoms, however! Its importance has to do with the potential to create long-term health problems, like osteoporosis (1, 2).

What Complications Can Vitamin D Deficiency Cause?

Some studies have linked low vitamin D with increased risk of tumours, autoimmune diseases, type 2 diabetes, heart disease, and high blood pressure, among other complications (3). These hypotheses still need to be confirmed by more viable studies. However, here’s what we do know vitamin D deficiency can lead to over time:

  • Rickets. When vitamin D deficiency affects small children, their bones weaken and become more prone to breaking (4). This produces bone deformities and delayed growth, among other signs.
  • Osteoporosis and Osteomalacia. These conditions may be a consequence of vitamin D deficiency for adults. Vitamin deficits can make the bones “softer”, more fragile, and more brittle. Osteoporosis can be painful and may increase the odds of breaking a bone (4).

What Are the Consequences of Vitamin D Deficiency?

This particular nutrient has been proven to benefit our bones, preventing fractures and falls (5). But it goes beyond that. The consequences of low vitamin D include (among others) (6):

  • Long-Term Risk of Osteoporosis. Vitamin D deficiency occurs frequently among older adults – especially in patients with osteoporosis (2, 7).
  • Respiratory Illness. Low vitamin D could lead to less control over asthma symptoms and certain respiratory infections.
  • Problems During Pregnancy. Vitamin D deficiency could lead to premature labour and low birth weight, to give just two examples.
  • Cardiovascular Diseases. Some studies have associated low vitamin D levels with higher cardiac risk (5).
  • Diabetes. Vitamin D supplements may reduce the risk of developing type 1 diabetes, though this finding is still awaiting further study (5).
  • Cancer. Certain types of cancer (including colon and breast cancer) are associated with vitamin D deficiency, though findings are still not definitive (2, 5).
  • Mental Illness. Some scientific studies have shown that insufficient vitamin D levels can make people prone to depression (5).
pregnant girl holding flowers
Mothers with low vitamin D may pass the deficiency onto their children, increasing the child’s risk of rickets. (Source: Mullins: y16sn3fcwiw/ Unsplash.com)

Who’s At Risk for Vitamin D Deficiency?

As I’m sure you know, the skin produces vitamin D when exposed to the sun, but it can also be obtained through food and dietary supplements. Who’s at risk for low levels of this nutrient? Let’s check off the list (1):

  • Those who don’t get enough sun. However, many variables influence sunlight’s effectiveness: the time of day, season, altitude, and altitude. You can also influence its effects with the clothes you wear, whether you use sunscreen, your skin colour, and your age. Plus, older adults’ skin can produce up to 75% less vitamin D than young people’s.
  • Those who don’t get enough in their diet. With the exception of oily fish, most foods have relatively low vitamin D content. That even includes dairy products artificially fortified with vitamin D. Vitamin D supplements are a safe fix (8), but sadly, vitamin D deficiency often goes undiagnosed.

What’s the Daily Recommended Dose of Vitamin D?

The daily intake you need will depend significantly on your age. Check the following table of the NHS’s recommended intake (9):

AgeRecommended Dietary Allowance (RDA)
Infants (0-12 months)8.5-10 mcg (340-400 UI)*
Children (1-13)10 mcg (400 UI)
Adolescents (14-18)10 mcg (400 UI)
Adults10 mcg (400 UI)
*The RDA is measured in micrograms (mcg) and International Units (IU).

How Can I Tell if I Have Low Vitamin D?

You can find out by visiting your doctor and having them perform a blood test to determine the amount of vitamin D in your body. All of these groups are at higher risk for vitamin D deficits (1):

  • People with conditions that hinder nutrient absorption. A common example is coeliac disease.
  • People with limited sun exposure. Older adults and small children are at increased risk, since they stay home more and are exposed to sunlight less.
  • People with renal insufficiency (kidney problems). When your kidneys don’t work properly, you may have trouble maintaining vitamin D reserves within healthy range. On top of that, vitamin D deficiency can aggravate kidney disease.
  • Pregnant and breastfeeding women. Mothers with low vitamin D may pass the deficiency onto their children, increasing the child’s risk of rickets (6).
  • People with intestinal or stomach problems. Any condition which affects the state of the intestinal tract can hinder vitamin D’s absorption.
girl takin a sun bath
If you don’t spend much time in the sun and you don’t include oily fish in your diet, it’s completely plausible that you may have low vitamin D. (Source: Om: 17415579/ 123rf.com)

How to Treat (and Prevent) Vitamin D Deficiency

Severely low vitamin D levels should always be treated by a doctor. Nevertheless, we can ensure we’re not prone to deficiency in the first place. This can be done by spending time in the sun, changing our eating habits, or using dietary supplements. And if you’ve read about liposomal supplements, you’ll know that they’re a revolutionary step forward!

Liposome Supplements

Let’s begin by explaining what liposomes are: small vessels made up of phospholipids, or molecules whose structure resembles our own cell membranes. They stably transport nutrients like vitamin D to the intestines, allowing for better absorption (10, 11).

Pharmaceutical research has long provided evidence of liposomes’ effectiveness when taking medications. Now, it’s also been demonstrated for nutritional supplements (12). In fact, research has shown all of these effects:

  • Greater bioavailability. A liposomal supplement can bring more active nutrients to their destinations in the body than traditional supplements (12).
  • Less stomach pain. Research has confirmed that liposomal formulas may lower the risk of gastrointestinal distress (13). Because the nutrient itself is isolated inside the liposome capsule, it cannot affect the walls of your digestive tract.
  • Cost-to-effectiveness value. Because the bioavailability is greater, the cost-benefit value of liposomal formulas is enormous. They’re far more efficient than other types of supplements.

Changing Your Eating Habits

Vitamin D is found naturally (though only in moderate amounts) in oily fish and egg yolks. If you’re looking to increase your reserves of this nutrient, we suggest you make changes to your diet. This table will show you some examples of foods with vitamin D, as well as their concentrations (6).

FoodIU Per ServingMcg Per ServingPercent Recommended Dietary Allowance (RDA)
Salmon (cooked) (85 grams)57014.2114%
Swordfish (cooked) (85 grams)56614.1113%
Cod liver oil (1 teaspoon)45011.290%
Canned sardines in oil (1 cup)2887.258%
Canned tuna (85 grams)681.714%
1 egg (cooked)441.19%
Slice of beef liver (81 grams)401.08%

Vitamin D3 is the main form of vitamin D found naturally in animal products and the oils from animal fats. It’s also found in many commercial vitamin supplements. Vitamin D2 (ergocalciferol) is naturally present in certain plants and mushrooms, and is used in supplements less often (6).

Don’t Forget to Get Some Sun!

You already know that sunlight stimulates vitamin D production – but how much sun should you get? And why is sunshine so important? We’ll explain it all, so take notes (14, 15)!

  • Why is sunshine important? The vitamin D produced by sunlight plays an important role in increasing how much calcium and phosphorus we absorb from food. Plus, it has crucial functions for bone development, immune system functioning, and blood cell formation.
  • How much time should I spend in the sun? Five to fifteen minutes, two to three times per week during the summer. Your hands, arms, and face should be exposed to direct sunlight. But of course, always remember to wear sunscreen when needed.
  • What problems are associated with it? We should note that the skin’s vitamin D production while exposed to the sun lessens with age. Lifestyle changes, including wearing different clothes and being active outdoors, are the determining factors there. You probably wouldn’t have guessed it, but air pollution is also an important variable which can lower vitamin D levels. Another issue, which I’m sure you’re familiar with, is that sun exposure accelerates the aging process and causes both wrinkles and skin cancers. Keep the risks in mind!

Our Conclusions

Have you been struggling with fatigue and achy bones? If you have, run to get a blood test and confirm your body has all the vitamin D it needs. And if you’re looking to prevent a deficiency in the first place, we suggest taking Sundt Nutrition’s liposomal supplements with a doctor’s approval. It’s a cutting-edge formula to meet your vitamin D needs.

Liposomal formulas ensure you can absorb optimal amounts of nutrients in a completely natural way. Sundt Nutrition products are gluten-free and sugar-free. But the best part is that, because they all use liposomes, their nutrients will enter your body intact. Worry no more about not getting enough sun in the winter!

If you liked this article, feel free to share it or leave us a comment with your questions. We can’t wait to hear your thoughts!

References(15)

  1. Vitamin D deficiency in adults: when to test and how to treat. Kurt A Kennel 1, Matthew T Drake, Daniel L Hurley Affiliations expand. PMID: 20675513 PMCID: PMC2912737 DOI: 10.4065/mcp.2010.0138. Review Mayo Clin Proc. 2010 Aug;85(8):752-7; quiz 757-8. doi: 10.4065/mcp.2010.0138. Available online:
  2. Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006;81:353-373 [PubMed] [Google Scholar]. Available online:
  3. Hossein-Nezhad A, Holick MF. Vitamin D for health: a global perspective. Mayo Clin Proc. 2013 Jul;88(7):720-55. Available online:
  4. Thacher TD, Fischer PR, Strand MA, Pettifor JM. Nutritional rickets worldwide: causes and future directions. Ann Trop Paediatr. 2006; 26 (1): 1-16 [PubMed] [Google Scholar]. Available online:
  5. Vitamin D Insufficiency. Tom D. Thacher, MD and Bart L. Clarke, MD. Mayo Clin Proc. 2011 Jan; 86(1): 50–60. doi: 10.4065/mcp.2010.0567. Available online:
  6. Global prevalence and disease burden of vitamin D deficiency: a roadmap for action in low- and middle-income countries. Daniel E. Roth, Steven A. Abrams, John Aloia, Gilles Bergeron,Megan W. Bourassa,Kenneth H. Brown, Mona S. Calvo, Kevin D. Cashman,Gerald Combs, Luz María De-Regil,9 Maria Elena Jefferds,Kerry S. Jones,a Hallie Kapner, Adrian R. Martineau,Lynnette M. Neufeld,Rosemary L. Schleicher,Tom D. Thacher, and Susan J. Whiting. Ann N Y Acad Sci. Author manuscript; available in PMC 2020 Jun 23. Published in final edited form as:Ann N Y Acad Sci. 2018 Oct; 1430(1): 44–79. Published online 2018 Sep 18. doi: 10.1111/nyas.13968 Available online:
  7. Vitamin D supplementation in the prevention and management of major chronic diseases not related to mineral homeostasis in adults: research for evidence and a scientific statement from the European society for clinical and economic aspects of osteoporosis and osteoarthritis (ESCEO. Luisella Cianferotti, Francesco Bertoldo, Heike A. Bischoff-Ferrari, Olivier Bruyere, Cyrus Cooper, Maurizio Cutolo, John A. Kanis, Jean-Marc Kaufman, Jean-Yves Reginster, Rene Rizzoli, Maria Luisa Brandi Endocrine. 2017; 56(2): 245–261. Published online 2017 Apr 7. doi: 10.1007/s12020-017-1290-9. PMCID: PMC6776482. Available online:
  8. Hathcock JN, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. I am J Clin Nutr. 2007; 85: 6-18. Available online:
  9. Informe del Comité Científico de la Agencia Española de Seguridad Alimentaria y Nutrición (AESAN) sobre Ingestas Nutricionales de Referencia para la población española. Available online:
  10. Keller B. Liposomes in nutrition. 2001. Available online:
  11. Bi Y et al. Liposomal Vitamin D3 as an Anti-aging Agent for the Skin. 2019. Available at:
  12. Liposomal-encapsulated Ascorbic Acid: Influence on Vitamin C Bioavailability and Capacity to Protect Against Ischemia–Reperfusion Injury. Janelle L. Davis, Hunter L. Paris, Joseph W. Beals, Scott E. Binns, Gregory R. Giordano, Rebecca L. Scalzo, Melani M. Schweder, Emek Blair and Christopher Bell. Journal ListNutr Metab Insightsv.9; 2016PMC4915787. Available online:
  13. Liposomes for Enhanced Bioavailability of Water-Insoluble Drugs: In Vivo Evidence and Recent Approaches. Mi-Kyung Lee. Pharmaceutics. 2020 Mar; 12(3): 264. Published online 2020 Mar 13. doi: 10.3390/pharmaceutics12030264 PMCID: PMC7151102 ArticlePubReaderPDF–2.9MCitation. Available online:
  14. The known health effects of UV. Newsroom. WHO TEAM Environment, Climate Change and Health. World Health Organization (Organización Mundial de la Salud u OMS, en español) Publicado el 16 de octubre de 2017.
  15. Vitamin D for Health: A Global Perspective Arash Hossein-nezhad, Michael F. HolickMayo Clin Proc. Author manuscript; available in PMC 2014 Jul 1.Published in final edited form as: Mayo Clin Proc. 2013 Jul; 88(7): 720–755. Published online 2013 Jun 18. doi: 10.1016/j.mayocp.2013.05.011PMCID: PMC3761874. Available online:

Advertising

Previous Vitamin D for Infants: How Much Do Babies Need? Next Vitamin C for the Skin
SCIENTIFIC ARTICLE
Vitamin D deficiency in adults: when to test and how to treat. Kurt A Kennel 1, Matthew T Drake, Daniel L Hurley Affiliations expand. PMID: 20675513 PMCID: PMC2912737 DOI: 10.4065/mcp.2010.0138. Review Mayo Clin Proc. 2010 Aug;85(8):752-7; quiz 757-8. doi: 10.4065/mcp.2010.0138. Available online:
Go to source
SCIENTIFIC ARTICLE
Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006;81:353-373 [PubMed] [Google Scholar]. Available online:
Go to source
SCIENTIFIC ARTICLE
Hossein-Nezhad A, Holick MF. Vitamin D for health: a global perspective. Mayo Clin Proc. 2013 Jul;88(7):720-55. Available online:
Go to source
SCIENTIFIC ARTICLE
Thacher TD, Fischer PR, Strand MA, Pettifor JM. Nutritional rickets worldwide: causes and future directions. Ann Trop Paediatr. 2006; 26 (1): 1-16 [PubMed] [Google Scholar]. Available online:
Go to source
SCIENTIFIC ARTICLE
Vitamin D Insufficiency. Tom D. Thacher, MD and Bart L. Clarke, MD. Mayo Clin Proc. 2011 Jan; 86(1): 50–60. doi: 10.4065/mcp.2010.0567. Available online:
Go to source
SCIENTIFIC ARTICLE
Global prevalence and disease burden of vitamin D deficiency: a roadmap for action in low- and middle-income countries. Daniel E. Roth, Steven A. Abrams, John Aloia, Gilles Bergeron,Megan W. Bourassa,Kenneth H. Brown, Mona S. Calvo, Kevin D. Cashman,Gerald Combs, Luz María De-Regil,9 Maria Elena Jefferds,Kerry S. Jones,a Hallie Kapner, Adrian R. Martineau,Lynnette M. Neufeld,Rosemary L. Schleicher,Tom D. Thacher, and Susan J. Whiting. Ann N Y Acad Sci. Author manuscript; available in PMC 2020 Jun 23. Published in final edited form as:Ann N Y Acad Sci. 2018 Oct; 1430(1): 44–79. Published online 2018 Sep 18. doi: 10.1111/nyas.13968 Available online:
Go to source
SCIENTIFIC ARTICLE
Vitamin D supplementation in the prevention and management of major chronic diseases not related to mineral homeostasis in adults: research for evidence and a scientific statement from the European society for clinical and economic aspects of osteoporosis and osteoarthritis (ESCEO. Luisella Cianferotti, Francesco Bertoldo, Heike A. Bischoff-Ferrari, Olivier Bruyere, Cyrus Cooper, Maurizio Cutolo, John A. Kanis, Jean-Marc Kaufman, Jean-Yves Reginster, Rene Rizzoli, Maria Luisa Brandi Endocrine. 2017; 56(2): 245–261. Published online 2017 Apr 7. doi: 10.1007/s12020-017-1290-9. PMCID: PMC6776482. Available online:
Go to source
SCIENTIFIC ARTICLE
Hathcock JN, Shao A, Vieth R, Heaney R. Risk assessment for vitamin D. I am J Clin Nutr. 2007; 85: 6-18. Available online:
Go to source
OFFICIAL DOCUMENT
Informe del Comité Científico de la Agencia Española de Seguridad Alimentaria y Nutrición (AESAN) sobre Ingestas Nutricionales de Referencia para la población española. Available online:
Go to source
SCIENTIFIC ARTICLE
Keller B. Liposomes in nutrition. 2001. Available online:
Go to source
SCIENTIFIC ARTICLE
Bi Y et al. Liposomal Vitamin D3 as an Anti-aging Agent for the Skin. 2019. Available at:
Go to source
SCIENTIFIC ARTICLE
Liposomal-encapsulated Ascorbic Acid: Influence on Vitamin C Bioavailability and Capacity to Protect Against Ischemia–Reperfusion Injury. Janelle L. Davis, Hunter L. Paris, Joseph W. Beals, Scott E. Binns, Gregory R. Giordano, Rebecca L. Scalzo, Melani M. Schweder, Emek Blair and Christopher Bell. Journal ListNutr Metab Insightsv.9; 2016PMC4915787. Available online:
Go to source
SCIENTIFIC ARTICLE
Liposomes for Enhanced Bioavailability of Water-Insoluble Drugs: In Vivo Evidence and Recent Approaches. Mi-Kyung Lee. Pharmaceutics. 2020 Mar; 12(3): 264. Published online 2020 Mar 13. doi: 10.3390/pharmaceutics12030264 PMCID: PMC7151102 ArticlePubReaderPDF–2.9MCitation. Available online:
Go to source
WHO OFFICIAL WEBSITE
The known health effects of UV. Newsroom. WHO TEAM Environment, Climate Change and Health. World Health Organization (Organización Mundial de la Salud u OMS, en español) Publicado el 16 de octubre de 2017.
Go to source
SCIENTIFIC ARTICLE
Vitamin D for Health: A Global Perspective Arash Hossein-nezhad, Michael F. HolickMayo Clin Proc. Author manuscript; available in PMC 2014 Jul 1.Published in final edited form as: Mayo Clin Proc. 2013 Jul; 88(7): 720–755. Published online 2013 Jun 18. doi: 10.1016/j.mayocp.2013.05.011PMCID: PMC3761874. Available online:
Go to source