Vitamin D Deficiency

Vitamin D Deficiency is something that can affect anyone despite age, gender, or ethnicity.  The likelihood of it developing does depend on several factors, however.  It is said that someone is Vitamin D Deficient when the amount of Vitamin D is inadequate which may have health consequences (Yale, 2025).  Vitamin D is important for the process of the body, including bone, to absorb Calcium, phosphorus, and Magnesium.  Vitamin D Deficiency causes these to not be absorbed well.  Vitamin D also plays an essential role in the nervous, musculoskeletal, and immune systems (Cleveland Clinic, 2022).  Vitamin D Deficiency can also be linked to  increased risk of:

• Cancer
• Heart Disease
• Stroke
• Depression
• Muscular Sclerosis
• Type 2 Diabetes (Watson, 2024)

Several things may contribute to someone developing Vitamin D Deficiency.  These include:

• Not enough exposure to sunlight
• Darker skin Pigment
• Malnutrition
• Kidney or Liver failure
• Certain medications
• Certain cancers
• Family history of  Vitamin D Deficiency or Childhood Rickets
• Chorn's Disease, Cystic Fibrosis, and Celiac Disease
• Obesity
• Weight Loss Surgery (Yale, 2025)(Watson, 2024)

There are also some risk factors for developing Vitamin D Deficiency including:

• Age - 65 years old or older
• BMI greater than or equal to 30
• Melanated skin
• Smoking
• Not eating foods fortified with Vitamin D (Watson, 2024).

Although he signs and symptoms may be more obvious in kids, there are also signs and symptoms in adults  In kids, signs and symptoms include:

• Weak, sore, painful muscles
• Incorrerct growth (bowed or bent legs)
• Muscle weakness
• Bone pain
• Joint deficiencies (Watson, 2024)

In adults, signs and symptoms include:

• Fatigue
• Bone and joint pain
• Muscle weakness, aches, or cramps
• Increased sensitivity to pain
• "Pins and needles" sensations in hands and feet
• Muscle spasms
• Waddling while walking due to muscle weakness i n hips and legs
• History of broken bones
• Mood changes (Yale, 2022)(Watson, 2024)

You may be wondering how much vitamin D people need each day.  Well, it is age dependant.

• Birth to 12 months - 400 IU
• 1-13 years - 600 IU
• 14 - 18 years - 600 IU
• 19 - 70 years - 600 IU
• 71 - older - 800 IU
• Breastfeeding or pregnant - 600 IU (Medline Plus, 2024)

Who are individuals who may be at risk for Vitamin D Deficiency?

• Breastfed infants - breast milk is low in vitamin D.  Infants who are sole breast fed should be given a vitamin D supplement equal to 400 IU every day.
• Older adults - skin does not make vitamin D as efficient as it did when someone is younger.  Also, Kidneys do not convert vitamin D to its active form as well.
• People with increased melenation (darker skin) - darker skin has decreased ability to produce vitamin D when exposed to sunlight.  
• People dealing with Obesity - body fat binds sone vitamin D which decreases the amount available in the blood stream.  Increased body fat binds more vitamin D removing more vitamin D from bloodstream.
• People who have had Gastric Bypass Surgery - this surgery bypasses part of small intestine where vitamin D is absorbed.  Having part of the small intestine bypassed affects absorption of vitamin D.
• People with Chronic Kidney or Liver Dizease - affects ability to change vitamin D into active form.
• People taking certain medications - certain cholesterol, anti-seizure and weight loss medications can affect vitamin D level. 
• People with Cystic Fibrosis, Chrohn's Dizease, and Celiac Disease - these conditions prevent vitamin absorption in intestines.
• People who do not spend a lot of time in the sun.  (Medline Plus, 2024)(Cleveland Clinic, 2022)

There is a blood test that can be done to determine vitamin D levels.  Those individuals who are at risk for Vitamin D Deficiency can have a 25 - hydroxyvitamin D [25(OH)D] blood test done (Watson, 2024).

Once Vitamin D Deficiency has been diagnosed, there are ways that it can be treated.

• Foods that naturally have vitamin D include:
• Fatty Fish - salmon, tuna, markel and sardines
• Rainbow Trout
• Beef liver
• Mushrooms
• Egg yolks
• Cod liver oil
• Foods that are often fortified with vitamin D include:
• Cow's, soy, almond and oat milk
• Breakfast cereals
• Orange juice
• Dairy products
• Vitamin D supplements may be taken.

Your healthcare provider should be consulted to determine the best way to increase vitamin D levels if deficient (Medline Plus, 2024).

What happens if you have too much vitamin D?

Although not common, it is possible to concume too much vitamin D, primarily through supplements.  Signs and symptoms of vitamin D toxicity include:

• Nausea
• Increased thirst and urination
• Poor Appetite
• Constipation
• Weakness
• Confusion
• Ataxia - impaired balance or coordination
• Dysarthria - unclear speech
• Irregular heartbeat
• Kidney Failure (Medline Plus, 2024)

Cleveland Clinic, (2022)  Vitamin D Deficiency.  Cleveland Clinic.  Retrieved from https://my.clevelandclinic.org/health/diseases/15050-vitamin-d-vitamin-d-deficiency#diagnosis-and-tests

Medline Plus. (2024)  Vitamin D Deficiency.  Medline Plus.  Retrieved from https://medlineplus.gov/vitaminddeficiency.html

Watson, L. (2024)  Vitamin D Deficiency.  WebMD.  Retrieved from https://www.webmd.com/diet/vitamin-d-deficiency

Yale. (2025) Vitamin D Deficiency.  Yale University.  Retrieved from https://www.yalemedicine.org/conditions/vitamin-d-deficiency