The Secrets of Vitamin D – What Causes Vitamin D Deficiency?

What Causes Vitamin D Deficiency?

There are actually several causes of vitamin D deficiency. The main problem is that vitamin D deficiency is not always easy to spot. You need to know what the symptoms are so that you can detect it. This probably explains why the experts think that more than a billion people across the globe have a deficiency in vitamin D.

We will discuss the symptoms of vitamin D deficiency in detail in the next section. Here we will look at some of the most common causes of vitamin D deficiency.

Your Diet can cause a Deficiency in Vitamin D

If you do not eat the types of food that enable the development of vitamin D then this can cause you to be deficient in the vitamin. The foods that help to develop vitamin D are animal-based and include:

  • Beef liver
  • Fish
  • Egg yolk
  • Fish oils
  • Fortified milk products

Vegans are more prone to vitamin D deficiency as they do not consume any of these foods. There are supplements available that vegans can take to make up for the vitamin D that they are losing out on.

You have Very Dark Skin

If you have very dark skin then the pigment or melanin can prevent the formation of vitamin D when you are out in the sun. This can apply if you have a tan as well as if your skin is naturally dark.

The bottom line here is that the darker your skin is, the less chance it will have to form vitamin D with exposure to direct sunlight. Even if you spend a lot of time sunbathing this can still be a problem.

You have a Problem with your Digestive Tract

Some people have a problem with their digestive tract which means that they cannot absorb dietary fat or vitamin D. If you have a medical condition such as cystic fibrosis, celiac disease, or Crohn’s disease these can limit the ability of your intestines to absorb the vitamin D that youconsume.

These medical conditions can restrict the absorption of dietary fats as well and because vitamin D is fat-soluble, this can result in the same problem occurring.

You are not getting enough Sunlight

Your skin can only make vitamin D when you are exposed to direct sunlight. If you do not venture outdoors very often, your chances of being deficient in vitamin D will rise significantly.

You may work a job that prevents you from getting much sunlight or you could be homebound. If you live in a northern latitude country youcan be deprived of enough sunlight. Wearing head coverings and robes for religious purposes can also limit exposure to the sun.

Living in an area that has a lot of pollution or smog can also restrict your sunlight exposure. Where you live can really make a difference as can the season and the time of day that you venture out into the sun. In some parts of the US such as Cleveland, Ohio, there will be no UV-B light for 6 months of the year due to the sun’s position and the ozone layer.

Please be aware that the sun is strongest between 10am and 3pm.

You are Overweight / Obese

Being overweight or obese can leave you vitamin D deficient. If you have a body mass index of 30 or more then your fat cells may not be efficient enough to extract the required vitamin D from your blood and circulate it around your body.

Your Kidneys cannot process Vitamin D properly

Your kidneys play an important role in the conversion of vitamin D into an active form. If your kidneys are damaged or diseased, or have slowed down due to age, they may be unable to perform the conversion process properly which will result in vitamin D deficiency.

You are an Older Person

It is more difficult for our skin to create vitamin D from sunlight as we get older. As you age, your kidneys tend to slow down as well, so there may be sufficient vitamin D in your blood but your kidneys are unable to perform the conversion process as efficiently as they used to.

You take Specific Medications

Unfortunately, there are many medications that can lead to a deficiency in vitamin D. If you take laxatives then you run the risk of the vitamin D, as well as other nutrients, being flushed from your digestive system before they can be absorbed. Taking steroids can also be a problem as they tend to reduce the absorption of calcium and this impairs the metabolism of vitamin D.

Vitamin D is derived from cholesterol, so if you are taking medications that lower cholesterol such as colestipol or satins this can lower vitamin D synthesis in your body.

Some weight loss drugs like orlistat can lower the levels of vitamin D absorption in your body. Vitamin D levels in your body can also be

affected by taking seizure control medication such as phenobarbital and phenytoin. In addition to this, thiazide diuretics such as indapamide and HCTZ (hydrochlorothiazide) will usually lower urinary calcium excretion. If you take vitamin D supplements with these thiazide

medications then you could be at risk of hypercalcemia.

In the next section, we will discuss vitamin D deficiency symptoms…

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