Vitamin D Deficiency: Symptoms, Treatments, Causes, and More

Written by Resurchify | Updated on: April 16, 2022

Have you ever heard people suggesting you to sit under the morning Sun because you’ll get vitamin D from it? Or have you heard that Vitamin D is important for our bones? But how?

Let’s understand what vitamins are; these are nutrients that we need in a very small amount. We cannot produce on our own, but we need them for regular growth and development. Vitamin D is one of the four fat-soluble vitamins- A, E, D and K. So what does this being fat-soluble mean? It means that vitamin D can be stored in our body as our body cells are surrounded by fatty layers, which easily allows the movement of these vitamins into the cell, making them easy to be stored. So, where do we get these vitamins? You’ll be surprised to know that maximum vitamin D comes from the UVB rays of the sun, for which it is also called the ‘sunlight vitamin.’ It is also found in fish, eggs, and fortified milk.

Let us understand this fat-soluble vitamin in a better way. Vitamin D is an important nutrient that helps our body to retain calcium and phosphorus, making it vital for building bones. Studies have also proven that it helps to boost immunity, reduces inflammations and supports other vital functioning of the body. The two forms of the vitamin are ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) which are present naturally and also in the form of supplements. The only difference is that D2 is produced in plants and fungi, and D3 in animals, including humans. When sunlight falls on our skin, the body starts to synthesize vitamin D, which gets stored in the fats present in our body and then released in the absence of sunlight.

But many times, the body does not fulfil the amount of vitamin D; one of the prime reasons is lack of sun exposure, which can result in weak bones or low bone density and, in extreme cases, osteoporosis and fractures (broken bones). This can be easily treated by supplements or good exposure to sunlight.

This article will educate us on the various symptoms caused due to vitamin D deficiency and the ways to treat them.

Why Is Vitamin D So Important For Living Beings?

You might have heard a lot about immunity and the ways to boost them during the COVID-19 pandemic. But how is the immune system regulated? The answer is vitamin D. It helps to regulate the body’s immune system and other cellular functioning of the body. Its antioxidant, anti-inflammatory and neuroprotective properties support brain cell activity and muscle functioning. Vitamin D also metabolizes glucose, stimulates calcium absorption in the intestine and maintains the serum calcium and phosphate concentrations, which helps in bone growth and prevents the sudden involuntary muscle cramp and spasm- hypocalcemic tetany. This makes Vitamin D vital for our overall growth and development.

How does Vitamin D synthesise?

As we read earlier, the major source of vitamin D is sunlight. The first step toward vitamin D synthesis in the skin from precursor to active. However, we also get some of them from the food we eat in a minimum quantity.

So when we get exposed to UV light, it triggers the conversion of cholesterol that is present under our skin surface, the epidermis called the 7D-hrdrocholestrol and converted it into cholecalciferol, also called Vitamin D3. This inactive vitamin D3- cholecalciferol now flows in our bloodstream and ultimately gets into our liver. In our liver, cholecalciferol comes across an enzyme called the 25-hydroxylase and gives 1 hydrogen to the 25th carbon of the cholecalciferol molecule. It turns it into 25- hydroxycholecalciferol, also called calcifediol. It then moves to the kidney, and one across another enzyme called one alpha-hydroxylase. This enzyme gives one hydrogen to the first carbon of calcifediol, giving a molecule 1, 25-dihydroxycholecalciferol, also called Calcitriol. Now we have an active form of vitamin D.

This is the way our body synthesizes vitamin D from sunlight. When we intake animal and plant products, the process is a slightly different one. It doesn’t have to come all the way from our skin; instead, it goes to our blood. We get it in the form of cholecalciferol or vitamin D3 when we ingest it from animal products like fish or liver. It enters the bloodstream via the same pathway mentioned above. However, if we ingest them through plant products, one of the main sources are the UV-activated mushrooms; we get ergocalciferol, otherwise called the vitamin D2, which travels to the liver and other the hydroxylation process through 25-hydroxylase, moving via calcifediol and moving to the kidneys and continues the further process.

So how does the doctor know if you are Vitamin D deficient or not? When you go for a blood test to check your vitamin D level, you are not testing Calcitriol or 1, 25-dihydroxycholecalciferol. You are actually testing calcifediol. You are always going to be producing that at all times, which is a good indicator of your baseline vitamin D, at least precursor.

But what does calcifediol do? It increases calcium in the blood and is needed to increase phosphate in the blood. This is stimulated, and calcium and phosphate level are too low, which means the thing that stimulates one alpha-hydroxylase is going to be low calcium and low phosphate. Low phosphate directly stimulates one-alpha-hydroxylase to activate (indirectly activated by low calcium). If the calcium level in the body is low, it travels to the parathyroid gland, located next to the two thyroid gland lobes in the neck. The parathyroid gland produces the parathyroid hormone (PTH) after being triggered by low calcium, which further triggers one alpha-hydroxylase. Now that we have active vitamin D, whose work is to increase the calcium and phosphate level, as the stimulus was a drop. It does this by increasing the absorption of calcium and phosphate in the gastrointestinal tract. It also increases the re-absorption of calcium and phosphate in the kidneys, throwing it back into the blood. Another important thing it does is that it increases osteoclast activity, which causes the release of calcium into the blood.

So the work of vitamin D is to release calcium and phosphates into the bloodstream together, and jointly they mineralize into the bone. So we absorb it in the gastrointestinal tract, go into the blood, and reabsorb it from the kidneys to the blood. The whole process carries on; some are in the blood, and some go back into the bones, deposit in the bone, and strengthen them.

But what if we don’t have vitamin D and only the Parathyroid hormone? The calcium level increases in the blood, but phosphate gets excreted through urine, disturbing the Calcium-phosphate bond and actually breaking down the bones, indicating Vitamin D deficiency.

Too Less Vitamin D

Vitamin D is a worldwide issue. Almost 50% of the world’s population is affected by this, and the major reason is the lack of sun exposure. An amazing fact is that the colour of our skin changes the amount of vitamin D our body produces. People with lighter skin produce five times more vitamin D as compared to those with darker skin. Let us know the reasons behind vitamin D deficiency-

Less sunlight exposure- People who live away from the equator are more likely to have vitamin D deficit than those who live near the equator, for obvious reasons- the amount of sunlight. People who are homebound keep their heads and exposed body parts to protect themselves from the sun and are prone to vitamin D deficiency. Winters are also one of these reasons.
Not consuming the recommended amount of products having Vitamin D- Now, people are slowly moving toward vegan products, which means they avoid all types of animal products, including milk and milk products. Most of the natural sources of Vitamin D are animal-based, like fatty fishes like tuna, mackerel, salmon, cheese, egg yolk, and liver. So it is essential to keep a balanced diet and maintain an adequate amount of food on your plate.
The digestive tract does not absorb vitamin D sufficiently- Due to conditions like celiac disease, cystic fibrosis, and Crohn’s disease, the digestive tract tends to absorb less vitamin D from ingestion. Dark skin caused is due to a pigment called melanin, which reduces the skin’s ability to absorb the UV light from the sun and synthesize vitamin D.
Obesity- Fat cells remove Vitamin D from the blood, altering its release into circulation. So people with BMI (body mass index) above 30 are likely to have less vitamin D in the blood.
Fat absorption- As we know by now, vitamin D is a fat-soluble vitamin that requires fats to be absorbed from the guts to the lymphatic system, then to the bloodstream and then to the tissues and organs. Suppose the absorption of the fat is less, caused due to some issues in the bile or intestinal tract, which does not allow absorption of the fats we intake. This can cause serious problems and diminishes vitamin D in the body.

So by the above points, we understood the reason behind less vitamin D in the body. But how much vitamin D does the body need? If a person is less than 1years, they need 600 IU, 1-70 years need 600 IU, and people above 70 years of age need 800 IU. Anything less than this at a particular age can trigger a medical condition caused due to vitamin D deficiency.

Symptoms Your Body Needs Vitamin D

For normal and healthy growth, vitamins are a must, and vitamin D is one of them. Certain vitamin deficiencies can take a toll on your health and cause massive health issues. But how would you know if you have less amount of this particular vitamin? The body starts to react and show symptoms which we need to pay attention to on time. The various signs of vitamin D deficiency are-

Bone Pain- Bone growth stops once a person reaches adulthood; however, new ones replace old bone tissues regularly. Vitamin D helps the body absorb new bone tissue development, and less vitamin can cause the bones to soften and pain. This condition is called osteomalacia or adult rickets.
Muscles Ache- Vitamin D plays an important role in the functioning of muscles. When metabolized, it promotes and ensures proper muscle contractions. It is also important for building muscle strength. If you notice any such muscle pain without exertions or have chronic muscle pains that do not respond to treatments, it might indicate that you have less vitamin D in your body.
Low Immune System- If you notice catching a cold and cough frequently, it may be a sign that your body needs Vitamin D. Vitamin D keeps our immune system strong, so it combats various infections and allergies.
Fatigue- This is another sign of vitamin D deficiency. But people often tend to ignore them as they associate them with various other factors. Vitamin D helps to produce energy and keep us going. If you are vitamin D deficient, you will feel tired and sluggish the whole day.
Hair Loss- Vitamin D stimulates healthy hair follicle growth. When hair follicles are healthy, they maintain good hair volume. If the body has less vitamin D, it can affect hair growth as well and cause hair to fall off. However, this isn’t the case for those who face hair loss due to ageing or have it in their genes.
Slow Healing Process- Vitamin D is vital for rebuilding the skin cells, and if it reduces, the healing process becomes much slower. It can cause issues after surgery and provoke deeper scars.
Mood Swings- Vitamin D is important for the brain’s functioning and your mood as well. Lower levels of Vitamin D can make you irritated low and dressed as well. Recent studies have proven that vitamin D improves the Neurotransmitters in the brain called monoamines, which include feel-good substances like dopamine and serotonin.

Illnesses caused due to vitamin D Deficiency

The bones are majorly affected if our body lacks vitamin D in. Bone softening is one of them causing rickets in children and osteomalacia in adults. Inadequate bone mineralization could be due to deficient or impaired vitamin D, calcium, and phosphate metabolism.

Both rickets in children and osteomalacia show symptoms like diffuse bone and joint pain, proximal muscle weakness, bone fragility high risk of fracture. Symptoms like muscle pain, spasm and numbness can also appear.

Symptoms of Rickets

Craniotabes- soft and thin skull bones
Delay Fontanelles closure
Genu Verum- Bow leg, where the legs curve outward at the knees
Prominent frontal bone and protruded abdomen
Rachitic rosary- This is an increase of the anterior rib ends at the costochondral junctions. It looks like little bumps on the chest.

Symptoms of Osteomalacia

Extreme pain in bones and muscles in the ribs, lower back, pelvis, hips and legs
Pain in joints while walking
Muscle cramps and spasm

Treatment

If someone is homebound for a long time, there might be chances of being a Vitamin D deficit. If you notice any such signs for prolonged time, it is suggested to get yourself checked and treated.

Go outdoors more often and allow your body to absorb sunlight and synthesize Vitamin D; early morning sunlight is suggested.
Eat food enriched with vitamin D, especially animal products like – liver, red meat, oily fish like salmon, sardines, herring and mackerel, Soy drinks, Orange juice, egg yolks and fortified foods – such as some fat spreads and breakfast cereals. Dietary supplements are also a good source of Vitamin D.
Vitamin D supplements are also a good way to help the body get it back.

Too much Vitamin D

Yes, you read that right! If there can be less vitamin D, it can get too much at times (more than 100 nanograms (ng) per mL), causing Hypervitaminosis D. People start to consume supplements to retain the lost vitamin D if they suffer from disorders like osteomalacia or rickets in children, as it’s the best way. But there are risks of overdosing on this nutrient, which is very toxic for the body to tolerate. If you notice a loss of appetite, high blood pressure and heart irregularities, too much urination, nausea, vomiting, constipation, diarrhoea, fatigue, dizziness, hallucinations, or confusion while you are consuming the vitamin D supplements over the course of time, it might be that you’ve overdosed the supplements. Let’s have a look at what can Hypervitaminosis D lead to:-

Stones- An increased amount of calcium can lead to calcium-based kidney stones.
Bone pains- Too much vitamin D causes hypercalcemia and cause pain in the bones and joints.
Abdominal Pain- When there is too much vitamin D floating in your blood, it starts to contract the smooth muscles of the abdomen, causing an unusual pain in the abdomen area.
Psychic groans- Too much calcium blocks the ability of neurons to function properly, causing depression in the nervous system.

Now you might be thinking, can excessive sun exposure cause vitamin D overdose? The answer is No, as the body knows how much vitamin D it needs. However, extreme sun exposure can surely cause skin-related issues and premature ageing. If you find yourself taking too many vitamin D supplements and face such overdose symptoms, it is suggested to stop them right away.

Conclusion

In the above article, we discussed the importance of vitamin D and how our body synthesis it. There are many ways our body can get Vitamin D, so an adequate amount of supplements are okay for the body, especially for those who live in areas getting less sunlight. But remember, too much of anything is toxic, and the same goes with any nutrient. Hence, it is advised to take such supplements with the doctor’s consultation after being diagnosed with less vitamin D.

Frequently Asked Questions

Can rickets affect adults?

Rickets is more common in small children cause due to lack of vitamin D. Adults face soft and deformed bones due to the same.

Can vitamin D help in weight loss?

Yes, some studies from the University of Milan have proven that vitamin D helps to lose weight for those who are overweight due to vitamin D deficiency. It is obvious as it promotes metabolism. But before any supplement consumption, get the check-up done.

How much is vitamin D too much and too less?

The recommended amount of Vitamin D intake per day is 20 micro gms. But above 100 micrograms (4,000 IU) for adults and 50 micrograms (2,000 IU) for children of 1-10years of age is too much. 12 ng/mL and below that is less for the body and causes vitamin D deficiency.

I am sweating excessively and experiencing unexpected weakness. Am I vitamin D deficit?

Excessive sweating, and unexpected weakness without any exertion can be visible signs of vitamin D deficiency. Get yourself tested and take the necessary medication.

Can pregnancy cause Vitamin D deficiency?

Yes, vitamin D deficiency is common during pregnancy but is preventable. Consult your doctor and maintain a healthy diet.

I am a vegan; can I be a Vitamin D deficit?

This may not be true in all cases. No matter what type you are, vegan, vegetarian or non-vegetarian. You can be vitamin D deficient and may need supplements. However, studies have proven that a vegan diet offers lesser vitamin D as compared to meat and milk diets.

What are the foods enriched in vitamin D?

Products like liver, red meat, oily fish like salmon, sardines, herring and mackerel, Soy drinks, Orange juice, egg yolks and fortified foods – such as some fat spreads and breakfast cereals are rich in vitamin D.

Why people who live in the extreme north are vitamin D deficient?

People who live in the northern area get very few chances of being exposed to sunlight, especially during the winter. The sunlight is the main source of Vitamin D. Therefore, northern latitudes dwellers are at significant risk of vitamin D deficiency during the winter season.

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