Updated on: October 17, 2026
Written by: Adel Galal, Founder and Lead Writer at NextFitLife
Medical review status: This article has not been medically reviewed by a doctor, endocrinologist, pediatrician, registered dietitian, pharmacist, or other licensed healthcare professional.
Vitamin D deficiency disease develops when the body has too little vitamin D to maintain normal calcium, phosphorus, bone, and muscle health.
Mild vitamin D deficiency may cause no clear symptoms. Severe or long lasting deficiency can interfere with normal bone mineralization. In children, this can cause rickets. In adults, it can cause osteomalacia, which may lead to bone pain, muscle weakness, walking problems, and fractures.
The condition cannot be diagnosed from tiredness, aches, or low mood alone. Those symptoms have many possible causes. When testing is medically appropriate, the main blood test is 25 hydroxyvitamin D, often written as 25(OH)D.
Treatment usually involves vitamin D replacement, adequate calcium intake when needed, and correction of the reason vitamin D became low. Very high supplement doses should not be taken without medical guidance because excess vitamin D can cause dangerous high calcium levels.
This article is for general information and education. It does not replace medical advice, diagnosis, or treatment.
For a broader introduction to vitamin D, read Vitamin D. You can also compare this guide with Vitamin D Deficiency and review our Low Calcium Signs and Symptoms guide.
Table of Contents
- What vitamin D deficiency disease means
- 12 warning signs and effects
- Bone pain
- Muscle weakness
- Difficulty climbing stairs
- Walking changes
- Bone tenderness
- Fractures
- Rickets
- Osteomalacia
- Muscle cramps and twitching
- Growth problems in children
- Low bone density
- No obvious symptoms
- Main causes
- Who is at higher risk
- Rickets explained
- Osteomalacia explained
- Vitamin D and calcium
- The right blood test
- Testing and diagnosis
- Food and sunlight
- D2 vs D3
- Treatment
- Vitamin D toxicity
- Frequently asked questions
What Is Vitamin D Deficiency Disease?
Vitamin D deficiency disease refers to health problems caused by too little vitamin D.
Vitamin D helps the body absorb and regulate:
- Calcium
- Phosphorus
These minerals help bones become hard and strong.
Vitamin D also supports:
- Muscle function
- Nerve function
- Normal immune function
When vitamin D becomes severely low, bone mineralization can fail.
This can result in:
- Rickets in children
- Osteomalacia in adults
Vitamin D Deficiency Is Not the Same as Osteoporosis
This distinction matters.
Osteomalacia means bone tissue is not mineralized properly, so the bones become softer.
Osteoporosis means bone strength and density are reduced, making fractures more likely.
A person can have:
- Vitamin D deficiency without osteoporosis
- Osteoporosis with normal vitamin D
- Both conditions at the same time
Read Osteoporosis for a full explanation.
12 Warning Signs and Effects of Vitamin D Deficiency Disease
1. Bone Pain
Severe vitamin D deficiency can lead to poor mineralization of bone.
This can cause deep, aching bone pain.
Common areas include:
- Lower back
- Pelvis
- Hips
- Ribs
- Legs
- Shoulders
Bone pain has many other causes, so it should not be diagnosed from symptoms alone.
2. Muscle Weakness
Muscle weakness is an important feature of severe deficiency and osteomalacia.
The weakness may be most obvious around the:
- Hips
- Thighs
- Shoulders
This is called proximal muscle weakness.
It can make normal daily tasks harder.
3. Difficulty Climbing Stairs
Weak muscles around the hips and thighs can make climbing stairs difficult.
Some people also struggle to:
- Rise from a chair
- Get up from the floor
- Walk uphill
- Carry out normal daily movement
This pattern deserves medical assessment when it is new or worsening.
4. Changes in Walking
Osteomalacia can make walking painful or tiring.
Weakness around the hips can change a person's gait.
Some people may:
- Walk more slowly
- Take shorter steps
- Avoid walking far
- Develop a waddling gait
Many neurologic, muscular, and joint conditions can also affect walking, so the cause needs evaluation.
5. Bone Tenderness
Severely undermineralized bone can become tender.
A clinician may find tenderness over areas such as the:
- Shins
- Ribs
- Pelvis
- Spine
Persistent bone tenderness should not be assumed to be ordinary muscle soreness.
6. Fractures
Weak or poorly mineralized bones can fracture more easily.
Osteomalacia may contribute to:
- Stress fractures
- Fractures after minor trauma
- Bone pain that later proves to be a small fracture
Older adults may also have osteoporosis at the same time, which adds further fracture risk.
Read Fracture Prevention for a broader bone safety plan.
7. Rickets in Children
Rickets occurs when growing bones do not mineralize normally.
Vitamin D deficiency is an important cause, although low calcium, low phosphorus, and inherited disorders can also cause rickets.
Possible signs include:
- Bowed legs
- Delayed growth
- Bone pain
- Muscle weakness
- Swelling near the wrists
- Skeletal deformity
- Delayed tooth development
A child with possible rickets needs medical evaluation.
8. Osteomalacia in Adults
Osteomalacia is the adult disorder of poor bone mineralization.
Common features include:
- Bone pain
- Muscle weakness
- Walking difficulty
- Difficulty climbing stairs
- Fractures
Vitamin D deficiency is one of the most common causes.
9. Muscle Cramps, Tingling, or Twitching
Severe vitamin D deficiency can sometimes lead to low calcium.
When calcium falls, symptoms may include:
- Tingling around the mouth
- Finger tingling
- Muscle cramps
- Twitching
- Muscle spasms
These symptoms are more closely related to the calcium disturbance than to vitamin D itself.
See Low Calcium Signs and Symptoms for more detail.
10. Growth Problems in Children
Children need normal bone mineralization while they grow.
Severe vitamin D deficiency and rickets may cause:
- Slower growth
- Short stature
- Skeletal deformity
- Delayed motor development in severe cases
Growth problems have many causes and should be evaluated professionally.
11. Low Bone Density or Increased Fracture Risk
Vitamin D deficiency can contribute to poor bone health because the body cannot handle calcium normally.
However, bone density also depends on:
- Age
- Hormones
- Genetics
- Calcium intake
- Exercise
- Smoking
- Alcohol
- Medicines
- Body weight
Vitamin D is part of the picture, not the whole picture.
12. You May Have No Clear Symptoms
Many people with low vitamin D have no obvious symptoms.
This is why a symptom checklist cannot confirm the diagnosis.
People may discover low vitamin D during testing for:
- Bone disease
- Malabsorption
- Low calcium
- Repeated fractures
- Other medical conditions
Symptoms That Do Not Prove Vitamin D Deficiency Disease
| Symptom | Why It Is Not Specific |
|---|---|
| Fatigue | Can come from anemia, thyroid disease, poor sleep, infection, depression, diabetes, medicines, and many other causes |
| Low mood | Mood symptoms have many medical and psychological causes |
| Hair loss | Common causes include genetics, iron deficiency, thyroid disease, hormones, stress, and scalp disorders |
| Joint pain | Arthritis, injury, tendon problems, gout, and other conditions are common causes |
| Frequent colds | Frequent respiratory infections do not diagnose vitamin D deficiency |
What Causes Vitamin D Deficiency Disease?
Vitamin D levels can become low for several different reasons.
1. Not Getting Enough Vitamin D From Food
Few foods naturally contain large amounts of vitamin D.
This means diet alone may provide too little when fortified foods and supplements are not used.
Food sources include:
- Fatty fish
- Egg yolks
- Some mushrooms
- Fortified milk
- Fortified plant milk
- Some fortified cereals
2. Limited Sunlight Exposure
The skin can produce vitamin D when ultraviolet B radiation reaches it.
Production may be lower in people who:
- Spend most of the day indoors
- Cover most of their skin
- Live in places with limited useful ultraviolet exposure during part of the year
- Have little outdoor activity
The amount of vitamin D produced from sunlight varies too much for a single universal minute target to work for everyone.
3. Darker Skin
Melanin reduces vitamin D production from sunlight.
People with darker skin may therefore have a higher risk of low vitamin D under some conditions.
This does not mean deliberate tanning or sunburn is recommended.
4. Older Age
The skin becomes less efficient at making vitamin D with age.
Older adults may also spend less time outdoors and may have other conditions that affect nutrition or vitamin D metabolism.
5. Malabsorption
Vitamin D is fat soluble.
Conditions that reduce nutrient or fat absorption can increase deficiency risk.
Examples include:
- Celiac disease
- Crohn disease
- Some cases of ulcerative colitis
- Pancreatic disorders
- Other malabsorption conditions
6. Bariatric Surgery
Some bariatric procedures reduce absorption of vitamin D, calcium, iron, vitamin B12, and other nutrients.
People who have undergone these procedures often need long term monitoring.
Read Bariatric Surgery for a broader overview.
7. Obesity
Vitamin D is fat soluble.
People with obesity often have lower circulating vitamin D concentrations.
This does not mean every person with obesity is deficient, but it can increase risk.
8. Kidney Disease
The kidneys convert vitamin D into its hormonally active form.
Chronic kidney disease can interfere with:
- Vitamin D activation
- Calcium balance
- Phosphorus balance
- Parathyroid hormone regulation
This creates a more complex mineral disorder than simple dietary deficiency.
9. Liver Disease
The liver converts vitamin D into 25 hydroxyvitamin D.
Severe liver disease can interfere with this step and contribute to abnormal vitamin D metabolism.
10. Certain Medicines
Some medicines can alter vitamin D absorption or metabolism.
Examples include selected:
- Anti seizure medicines
- Steroids
- Weight loss medicines
- Other drugs that affect absorption or vitamin metabolism
Do not stop a prescribed medicine because you are worried about vitamin D.
Who Is at Higher Risk?
People at higher risk can include:
- Breastfed infants without recommended vitamin D supplementation
- Older adults
- People with darker skin
- People with very little sun exposure
- People with malabsorption
- People with obesity
- People who have had gastric bypass or other bariatric procedures
- People with chronic kidney disease
- People with chronic liver disease
- People taking medicines that affect vitamin D
- People with osteomalacia
- People with rickets
- People with recurrent fractures or other bone disease
What Exactly Is Rickets?
Rickets affects growing bones in children.
The bones fail to mineralize normally at the growth plates.
Vitamin D deficiency is an important cause, but rickets can also result from:
- Low calcium
- Low phosphate
- Inherited phosphate disorders
- Inherited vitamin D metabolism disorders
- Kidney disorders
This is why a child with suspected rickets needs proper testing rather than vitamin D alone without evaluation.
Possible Signs of Rickets
Signs may include:
- Bowed legs
- Bone pain or tenderness
- Swollen wrists
- Slow growth
- Muscle weakness
- Delayed tooth eruption
- Skeletal deformity
Severe disturbances of calcium may also cause spasms or seizures.
What Exactly Is Osteomalacia?
Osteomalacia means adult bone is not mineralizing normally.
This makes the bone softer and weaker.
Possible symptoms include:
- Diffuse bone pain
- Hip or pelvic pain
- Back pain
- Rib pain
- Muscle weakness
- Difficulty walking
- Difficulty climbing stairs
- Fractures
Rickets vs Osteomalacia vs Osteoporosis
| Condition | Main Problem | Typical Group |
|---|---|---|
| Rickets | Poor mineralization of growing bone | Children |
| Osteomalacia | Poor mineralization of adult bone | Adults |
| Osteoporosis | Reduced bone strength and increased fracture risk | Most common in older adults |
How Vitamin D Controls Calcium and Phosphorus
Vitamin D helps the intestine absorb calcium.
It also supports normal phosphorus balance.
When vitamin D becomes severely deficient, calcium absorption can fall.
The parathyroid glands may respond by increasing parathyroid hormone, or PTH.
This helps defend blood calcium but can increase calcium release from bone and alter phosphorus handling.
Over time, normal bone mineralization can fail.
Can Vitamin D Deficiency Cause Low Calcium?
Yes.
Severe deficiency can contribute to hypocalcemia.
Symptoms of low calcium may include:
- Tingling around the lips
- Tingling in the fingers
- Muscle cramps
- Twitching
- Spasms
Severe hypocalcemia can cause seizures or dangerous heart rhythm changes.
What Is the Best Blood Test for Vitamin D?
The main blood test is:
25 hydroxyvitamin D, or 25(OH)D.
This reflects vitamin D obtained from:
- Food
- Supplements
- Vitamin D made by the skin
Why Not Test Active Vitamin D Instead?
The active hormone is called 1,25 dihydroxyvitamin D, or calcitriol.
It is not usually the right test for routine vitamin D status.
Its level can sometimes remain normal or even rise despite low vitamin D stores because the body tightly regulates it.
Doctors use it for selected kidney, calcium, parathyroid, or rare metabolic conditions.
Should Every Healthy Adult Get a Vitamin D Test?
No.
The 2024 Endocrine Society guideline advises against routine 25(OH)D screening in healthy adults who do not have an established reason for testing.
Testing can be more appropriate when there is:
- Rickets
- Osteomalacia
- Low calcium
- Malabsorption
- Bariatric surgery
- Kidney disease
- Liver disease
- Repeated fractures
- Another strong clinical reason
What Other Tests May Be Needed?
If vitamin D deficiency disease is suspected, clinicians may also check:
- Calcium
- Phosphate
- Alkaline phosphatase
- Parathyroid hormone
- Magnesium
- Kidney function
- Liver function
Children with suspected rickets or adults with suspected osteomalacia may also need imaging or other specialist tests.
What Vitamin D Level Counts as Deficient?
This question is more complex than many online charts suggest.
Laboratories and professional groups may use different labels such as:
- Deficient
- Insufficient
- Sufficient
- Possible toxicity
The 2024 Endocrine Society guideline no longer endorses one universal outcome based blood threshold for healthy people.
This means a result should be interpreted with:
- The reason the test was ordered
- Symptoms
- Bone health
- Calcium
- Kidney function
- Risk factors
- Your laboratory's reference range
How Much Vitamin D Do People Need?
| Age or Group | General Daily Intake |
|---|---|
| Birth to 12 months | 400 IU |
| Children and teens age 1 to 18 | 600 IU |
| Adults age 19 to 70 | 600 IU |
| Adults age 71 and older | 800 IU |
| Pregnancy | 600 IU |
| Breastfeeding | 600 IU |
These are general dietary reference amounts.
They are not treatment doses for confirmed vitamin D deficiency disease.
Vitamin D Rich Foods
Few foods naturally contain much vitamin D.
Fatty fish
- Salmon
- Trout
- Mackerel
- Sardines
- Tuna
Egg yolks
Egg yolks contain some vitamin D, although generally less than fatty fish.
Mushrooms
Some mushrooms provide vitamin D, particularly when exposed to ultraviolet light.
Fortified foods
Depending on the country and product, vitamin D may be added to:
- Milk
- Plant milk
- Breakfast cereals
- Yogurt
- Some juices
Check the nutrition label because amounts vary.
Can Food Alone Treat Vitamin D Deficiency Disease?
Mild low intake may improve with dietary changes, but confirmed deficiency often requires supplementation because relatively few foods contain large amounts of vitamin D.
The required dose depends on:
- Severity
- Age
- Body size
- Malabsorption
- Kidney function
- Liver function
- Medicines
- Whether rickets or osteomalacia is present
Can Sunlight Treat Vitamin D Deficiency?
Sunlight helps the skin make vitamin D, but the amount produced varies greatly.
Important factors include:
- Season
- Latitude
- Time of day
- Skin pigmentation
- Age
- Clothing
- Cloud cover
- Air pollution
This makes simple claims such as “10 minutes in the sun fixes vitamin D” unreliable.
Should You Tan to Raise Vitamin D?
No.
Sunburn and deliberate tanning are not safe vitamin D treatments.
Ultraviolet exposure can damage skin and increase skin cancer risk.
Food and supplements provide more controlled vitamin D intake when treatment is required.
Vitamin D2 vs Vitamin D3
Two common forms are:
- Vitamin D2, or ergocalciferol
- Vitamin D3, or cholecalciferol
Both can increase blood vitamin D.
D3 may maintain levels more effectively in some situations, but either form may be prescribed.
Check all supplements so you do not accidentally take vitamin D from several products at the same time.
How Is Vitamin D Deficiency Disease Treated?
The basic approach is to replace vitamin D and treat the cause.
Treatment may include:
- Vitamin D supplements
- Adequate calcium intake
- Treatment for malabsorption
- Medicine review
- Kidney specific treatment
- Liver disease management
- Follow up testing when appropriate
Rickets and osteomalacia may require more careful calcium and mineral management than simple mild vitamin D deficiency.
Should You Take a Huge Weekly Vitamin D Dose?
Do not copy someone else's prescription.
Doctors sometimes use specific replacement schedules for documented deficiency, but the right dose depends on the clinical situation.
For adults age 50 and older who have an indication for vitamin D treatment, the 2024 Endocrine Society guideline favors daily lower dose vitamin D over occasional large doses.
How Long Does Treatment Take?
There is no single recovery timeline.
Vitamin D blood levels may begin changing within weeks.
Bone pain, weakness, and osteomalacia can take longer to recover.
Recovery depends on:
- The starting vitamin D level
- The treatment dose
- Calcium intake
- Absorption
- Kidney function
- Liver function
- The underlying cause
- How advanced the bone problem is
When Should Vitamin D Be Rechecked?
Routine repeated testing is not needed for every healthy person taking ordinary dietary amounts.
If you are being treated for documented deficiency or a deficiency disease, your healthcare professional may repeat 25(OH)D after enough time has passed to assess the response.
People with malabsorption, kidney disease, severe deficiency, unusual dosing, or persistent symptoms may need closer monitoring.
Vitamin D Deficiency Disease in Pregnancy
Vitamin D is important during pregnancy for maternal and fetal health.
The 2024 Endocrine Society guideline suggests empiric vitamin D supplementation during pregnancy because trials suggest potential benefits for several pregnancy outcomes.
This does not mean taking megadoses.
A prenatal supplement and individualized medical advice are safer than self prescribing large amounts.
Vitamin D Deficiency Disease in Babies
Breast milk contains little vitamin D.
Infants who are mainly breastfed are therefore at risk unless appropriate vitamin D supplementation is provided.
Severe deficiency in infancy can lead to rickets.
Parents should follow pediatric recommendations for infant vitamin D rather than estimating doses themselves.
Vitamin D in Adults Over 75
The 2024 Endocrine Society guideline suggests empiric vitamin D supplementation for adults older than 75 because of a potential mortality benefit.
This is a prevention recommendation.
It is different from treating severe vitamin D deficiency disease.
Vitamin D and Osteoporosis
Vitamin D supports calcium absorption and bone health.
But osteoporosis treatment may also involve:
- Adequate calcium
- Strength training
- Weight bearing activity
- Fall prevention
- Smoking cessation
- Reduced excess alcohol
- Prescription osteoporosis medicine
Vitamin D alone is not a complete osteoporosis treatment.
Read Osteoporosis Treatment.
Can Vitamin D Cure Fatigue?
No.
If deficiency is contributing to weakness or tiredness, correcting it may help.
But fatigue can also be caused by:
- Iron deficiency
- Vitamin B12 deficiency
- Thyroid disease
- Sleep apnea
- Poor sleep
- Diabetes
- Depression
- Infection
- Medicine effects
Persistent fatigue should be investigated rather than blamed automatically on vitamin D.
Can Vitamin D Deficiency Cause Joint Pain?
Vitamin D deficiency can cause bone and muscle symptoms, but it does not explain every painful joint.
Joint pain more commonly comes from:
- Osteoarthritis
- Inflammatory arthritis
- Gout
- Tendon disorders
- Bursitis
- Injury
See How to Relieve Joint Pain.
Can Vitamin D Deficiency Cause Knee Pain?
Low vitamin D may contribute to general bone or muscle symptoms, but most knee pain has another cause.
Common knee problems include:
- Osteoarthritis
- Meniscus injury
- Ligament injury
- Patellofemoral pain
- Tendon problems
- Gout
Vitamin D does not repair damaged cartilage or a torn ligament.
Read How to Get Rid of Knee Pain Fast.
Can Vitamin D Deficiency Cause Low Calcium?
Yes, especially when the deficiency is severe.
Vitamin D is needed for efficient calcium absorption from the intestine.
If calcium becomes significantly low, symptoms can include tingling, cramps, twitching, spasms, and in severe cases seizures or abnormal heart rhythm.
Can Too Much Vitamin D Cause Disease?
Yes.
Too much vitamin D from supplements can cause vitamin D toxicity.
The main problem is excessive calcium in the blood.
This is called hypercalcemia.
Vitamin D Toxicity Symptoms
Possible symptoms include:
- Nausea
- Vomiting
- Poor appetite
- Constipation
- Weakness
- Weight loss
- Confusion
- Excessive thirst
- Frequent urination
Severe toxicity can damage the kidneys and cause abnormal heart rhythms.
Can Sun Exposure Cause Vitamin D Toxicity?
No.
Vitamin D toxicity is usually caused by excessive supplement intake.
The skin regulates vitamin D production from sunlight, so ordinary sun exposure does not cause vitamin D poisoning.
However, excessive ultraviolet exposure can still damage the skin.
Common Vitamin D Deficiency Disease Myths
| Myth | Better Explanation |
|---|---|
| Fatigue proves vitamin D deficiency | Fatigue has many causes and cannot diagnose deficiency alone. |
| Everyone needs an annual vitamin D test | Routine testing is not recommended for every healthy adult. |
| More vitamin D is always better | Too much can cause hypercalcemia and kidney injury. |
| Sunbathing is the safest treatment | Deliberate tanning increases skin damage and is not a controlled treatment dose. |
| Vitamin D cures every ache | Pain has many possible causes unrelated to vitamin D. |
| Osteoporosis and osteomalacia are the same | Osteomalacia is poor mineralization. Osteoporosis is reduced bone strength and density. |
A Practical Vitamin D Deficiency Disease Action Plan
- Do not diagnose deficiency from fatigue or aches alone.
- Ask whether there is a medical reason to test vitamin D.
- Use 25 hydroxyvitamin D as the main vitamin D status test.
- Check calcium and phosphorus when bone disease is suspected.
- Consider PTH when calcium or mineral balance is abnormal.
- Look for malabsorption when deficiency keeps returning.
- Review kidney and liver health when appropriate.
- Review medicines that can affect vitamin D.
- Use vitamin D rich or fortified foods.
- Use supplements in an appropriate dose.
- Make sure calcium intake is adequate when medically appropriate.
- Avoid megadose treatment without supervision.
- Recheck levels when your treatment plan calls for it.
- Seek medical assessment for bone pain, weakness, fractures, rickets, or osteomalacia.
When Should You See a Doctor?
Arrange medical assessment if you or your child has:
- Persistent bone pain
- Significant muscle weakness
- Difficulty climbing stairs
- Difficulty walking
- Repeated fractures
- Possible rickets
- Possible osteomalacia
- Known malabsorption
- Bariatric surgery history
- Chronic kidney disease
- Chronic liver disease
- Symptoms after very high vitamin D supplement doses
When Is It an Emergency?
Seek urgent medical help for:
- Seizure
- Severe muscle spasms
- Tetany
- Trouble breathing
- Fainting
- Severe confusion
- Serious abnormal heartbeat symptoms
- Severe vomiting or weakness after high dose vitamin D use
Conclusion: Treat Vitamin D Deficiency Disease Safely
Vitamin D deficiency disease is more than a low number on a laboratory report. Severe deficiency can disrupt calcium and phosphorus balance, weaken bone mineralization, cause rickets in children, and lead to osteomalacia, bone pain, muscle weakness, and fractures in adults.
The safest approach is to identify why vitamin D is low, use the right blood test when testing is appropriate, treat the deficiency at an appropriate dose, and address calcium, malabsorption, kidney disease, liver disease, or medicines when they contribute.
Do not chase a very high vitamin D number. The goal is adequate vitamin D and healthy bones, not megadosing.
If you have persistent bone pain, muscle weakness, repeated fractures, or another strong risk factor, ask your healthcare professional whether vitamin D testing and a full bone mineral assessment are appropriate.
References and Sources
- National Institutes of Health Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals.
Covers vitamin D metabolism, dietary needs, risk groups, food sources, deficiency, bone health, supplement safety, and toxicity.
https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/ - MedlinePlus. Vitamin D Deficiency.
Covers causes, risk groups, rickets, osteomalacia, food sources, supplements, recommended intake, and vitamin D toxicity.
https://medlineplus.gov/vitaminddeficiency.html - MedlinePlus. Vitamin D Test.
Covers 25 hydroxyvitamin D testing, indications for testing, deficiency risk, rickets, osteomalacia, low bone density, and treatment monitoring.
https://medlineplus.gov/lab-tests/vitamin-d-test/ - Endocrine Society. Vitamin D for the Prevention of Disease Clinical Practice Guideline.
The 2024 guideline covers routine testing, supplementation in children, pregnancy, adults over 75, and preference for daily lower doses in older adults when treatment is indicated.
https://www.endocrine.org/clinical-practice-guidelines/vitamin-d-for-prevention-of-disease - MedlinePlus. Rickets.
Covers vitamin D, calcium and phosphorus related rickets, growth problems, skeletal deformity, risk groups, testing, and treatment.
https://medlineplus.gov/rickets.html - MedlinePlus Medical Encyclopedia. Osteomalacia.
Covers adult bone softening, vitamin D deficiency, low calcium, causes, symptoms, testing, and treatment.
https://medlineplus.gov/ency/article/000376.htm - NHS. Rickets and Osteomalacia.
Covers bone pain, muscle weakness, walking difficulty, fractures, rickets, osteomalacia, testing, vitamin D, calcium, and treatment.
https://www.nhs.uk/conditions/rickets-and-osteomalacia/
Internal Links and Helpful NextFitLife Guides
- Vitamin D Deficiency: 11 Clear Signs and Safe Fixes
- Vitamin D: Benefits, Deficiency and Safe Use
- Low Calcium Signs and Symptoms
- Osteoporosis
- Osteoporosis Treatment
- How to Prevent Osteoporosis
- Best Way to Treat Osteoporosis Naturally
- Fracture Prevention
- How to Relieve Joint Pain
- Bariatric Surgery
- NextFitLife Health Hub
About the Author
Adel Galal is the Founder and Lead Writer at NextFitLife. He researches vitamin and mineral health, bone health, nutrition, metabolic health, healthy aging, and practical evidence based health guidance and turns current medical and public health information into clear explanations for everyday readers.
I am not a doctor or licensed healthcare professional, and this content does not replace professional medical advice, diagnosis, or treatment. I share information based on extensive research, real life experience, and consultation with healthcare providers. Always consult a qualified healthcare professional for diagnosis, treatment, or guidance about any health condition.
Learn more about Adel Galal, NextFitLife, and the site's editorial approach on the About Us page.
Frequently Asked Questions
What is vitamin D deficiency disease?
Vitamin D deficiency disease refers to health problems caused by too little vitamin D. Severe deficiency can disrupt normal bone mineralization and cause rickets in children or osteomalacia in adults.
What are the main symptoms of vitamin D deficiency disease?
Severe deficiency may cause bone pain, muscle weakness, difficulty walking, trouble climbing stairs, bone tenderness, fractures, rickets, or osteomalacia. Mild deficiency may cause no clear symptoms.
What disease is caused by vitamin D deficiency in children?
Severe vitamin D deficiency can cause rickets in children. Rickets causes weak, poorly mineralized growing bones and can lead to bone pain, growth problems, and skeletal deformity.
What disease is caused by vitamin D deficiency in adults?
Severe deficiency can cause osteomalacia in adults. Osteomalacia causes soft, poorly mineralized bones, bone pain, muscle weakness, walking difficulty, and fractures.
Is osteomalacia the same as osteoporosis?
No. Osteomalacia is poor bone mineralization, while osteoporosis is reduced bone strength and density. A person can have either condition or both.
What causes vitamin D deficiency disease?
Causes include low vitamin D intake, limited sunlight, darker skin, older age, malabsorption, obesity, bariatric surgery, kidney disease, liver disease, and medicines that affect vitamin D.
Can vitamin D deficiency cause low calcium?
Yes. Vitamin D helps the intestine absorb calcium. Severe deficiency can reduce calcium absorption enough to contribute to hypocalcemia.
What blood test checks vitamin D?
The main test is 25 hydroxyvitamin D, also called 25(OH)D. It reflects vitamin D from food, supplements, and skin production.
Should everyone get a vitamin D test?
No. Routine screening is not recommended for every healthy adult. Testing is more useful when there is rickets, osteomalacia, low calcium, malabsorption, bone disease, or another clinical reason.
What foods contain vitamin D?
Vitamin D sources include fatty fish, egg yolks, some mushrooms, and fortified foods such as certain milk products, plant milks, cereals, and yogurts.
Can food alone treat vitamin D deficiency disease?
Food helps, but confirmed deficiency often needs a vitamin D supplement because few foods naturally contain large amounts. Severe disease may also require calcium and treatment of the underlying cause.
Does sunlight treat vitamin D deficiency disease?
Sunlight helps the skin make vitamin D, but production varies greatly. Deliberate tanning or sunburn is not a safe or controlled treatment.
Is vitamin D3 better than vitamin D2?
Both vitamin D2 and D3 can raise vitamin D levels. D3 may maintain levels more effectively in some situations, but either can be used depending on the treatment plan.
How long does vitamin D deficiency take to improve?
Blood levels may begin improving within weeks, while recovery from bone pain, muscle weakness, or osteomalacia can take longer. The timeline depends on the cause and severity.
Can vitamin D deficiency cause fatigue?
Deficiency may contribute to tiredness in some people, but fatigue has many other causes and does not diagnose vitamin D deficiency on its own.
Can vitamin D deficiency cause joint pain?
Vitamin D deficiency can cause bone and muscle symptoms, but it is not the cause of every painful joint. Arthritis, gout, injury, and tendon problems are common alternatives.
Can children get rickets even if they take vitamin D?
Yes. Not all rickets is caused by simple vitamin D deficiency. Calcium deficiency, phosphate disorders, kidney conditions, and inherited problems can also cause rickets.
Can adults get rickets?
The adult disorder of poor bone mineralization is usually called osteomalacia. Rickets specifically affects growing bones in children.
Can too much vitamin D be dangerous?
Yes. Excess supplementation can cause high blood calcium, nausea, vomiting, weakness, confusion, kidney damage, excessive thirst, frequent urination, and abnormal heart rhythm.
When should vitamin D deficiency disease be medically evaluated?
Seek medical assessment for persistent bone pain, significant muscle weakness, walking difficulty, repeated fractures, suspected rickets or osteomalacia, malabsorption, kidney disease, liver disease, or symptoms after taking very high vitamin D doses.
Health & wellness writer with 30+ years of experience in nutrition, fitness, and healthy aging. Founder of NextFitLife.com — evidence-based health guidance.
