Supplement Savvy: Vitamin D

Vitamin D is an extremely important fat-soluble vitamin that has a crucial role in many vital processes in the body, yet Vitamin D insufficiency and deficiency are extremely common. As a matter of fact, Vitamin D deficiency is a global wide issue, with a billion or more people worldwide, and up to 42% of people in the US estimated to be Vitamin D deficient. But the good news here is that Vitamin D deficiency is treatable and preventable.

What Is Vitamin D and What Does it Do?

Vitamin D is known as the “sunshine vitamin” because your body produces Vitamin D when you are in the sun. It is a fat-soluble vitamin, meaning that it is stored in the body’s fat and liver, which keeps it in the body longer than water-soluble vitamins. Vitamin D is found as D2 (Ergocalciferol) which is plant based, and D3 (Cholecalciferol), which is animal based. Your body can more readily absorb D3 than it can D2.

Vitamin D helps you build healthy bones and keep them strong. You must have Vitamin D to absorb calcium from your small intestine, and calcium is a major part of your bones. Untreated Vitamin D deficiency can cause a condition called hypocalcemia, which means there is not enough calcium in your blood. This in turn can cause soft bones (Osteomalacia in adults or Ricketts in children) or brittle bones (Osteoporosis).  In one study, more than half of post-menopausal women with Osteoporosis had Vitamin D deficiency (“What Does Vitamin D Do?”, Cleveland Clinic Health, online, 2024).

Vitamin D also plays a role in helping your immune system. Having good levels of Vitamin D have been shown to help prevent infections, while low levels of Vitamin D are associated with a higher risk of infection, especially those that affect the respiratory system.  Vitamin D deficiency has also been linked to an increased risk of developing auto-immune diseases such as Lupus, Multiple Sclerosis, Rheumatoid Arthritis, IBS, and even certain cancers.

What are the Symptoms of Vitamin D Deficiency?

Some people are Vitamin D deficient or have insufficient intake of Vitamin D and have no symptoms, but other people may have:

• Mood Changes

• Bone Loss

• Muscle Cramps

• Bone and Joint Pain

• Fatigue

Why are People Deficient in Vitamin D?

There are several reasons why people are deficient or get an insufficient amount of Vitamin D. One reason is that they don’t get enough Vitamin D through diet or sunlight. Another reason is that they can’t absorb vitamin D because of certain medical conditions or medicines. 

There are foods that have Vitamin D in them including:

• Salmon 

• mushrooms

• egg yolks

•  fortified milk and cereal 

• Liver

But it is sometimes very difficult to get enough Vitamin D through food.

Wearing sunscreen, having darker skin, being older or not being outside much can affect how much Vitamin D you have.

Certain gut problems such as Crohn’s Disease, Celiac Disease, or history of gastric bypass surgery can affect absorption of Vitamin D. In addition, there are a lot of drugs that can affect Vitamin D absorption. Statin drugs for cholesterol, PPI drugs such as Omeprazole for gastric reflux, certain diuretics, laxatives, some seizure drugs, some blood pressure medications and Orlistat which is a weight loss medicine are a few, but there are others.

How Do You Know If You Are Vitamin D Deficient?

The best way to know if you are Vitamin D deficient is to have a blood test. Always discuss any supplements or over-the-counter medications with your own healthcare provider. Many people do need Vitamin D supplementation, but because Vitamin D is fat soluble it is possible to get too much, and Vitamin D does have some drug interactions, so it is important to always discuss this with them.  If it is determined that you do need a supplement, your provider may give you a prescription for D2 (Ergocalciferol) or may suggest a D3 supplement over the counter.

How Much Vitamin D Do You Need? 

The recommended daily amount of Vitamin D for adults is 600 IU (International Units) for adults up to age 70, then 800 IU for adults over 70 (Mayo Clinic, Online, 2024). There are times when this might be more, depending on what is recommended by your healthcare provider.  When choosing an over the counter supplement or vitamin, always look for a company that does third party testing and that has good reviews.