Vitamin D: A Pharmacist’s Guide to Why It Matters for Your Health

Sunshine vitamin, my favorite kind of vitamin D! Did you know your skin produces vitamin D?! It sure does and it’s my favorite way of getting vitamin D. But as we all know too much of a good thing can be bad for us. Too much sunshine leads to skin damage, aging skin, and possible skin cancer. And your skin can only make so much vitamin D for your body. Let’s dive into what vitamin D is, what it does for our health, and why some people may need vitamin D supplements. 

1. What is Vitamin D?

Vitamin D is a fat soluble vitamin that is found naturally in some foods, can be added to foods like milk, can be taken as a supplement, and can be produced by the skin from sunlight. 

2. What does Vitamin D do for our bodies?

Vitamin D helps with absorption of calcium and phosphorus, two minerals that help maintain bone health in our bodies. Low vitamin D levels often lead to low calcium, which in turn can weaken bones and lead to osteoporosis, increased risk of falls and possible fractures. Vitamin D also plays a role in immune function.

There are claims that vitamin D helps with disease like cancer, heart disease, and mental health disorders, but as of now data has not proven benefit. 

3. What are the differences between Vitamin D2 and Vitamin D3?

Vitamin D3 = Cholecalciferol

• Cholecalciferol is a form of Vitamin D that can be formed by the skin when exposed to sunlight. You can also get it from some foods and dietary supplementation.
• Found in animal-sourced foods:
  • Fatty Fish (trout, salmon, tuna) and Fish oil
  • Liver
  • Egg yolk
  • Butter

Vitamin D2 = Ergocalciferol

• Ergocalciferol is synthetic and often fortified in milk, infant formula, breakfast cereal, and other foods
• Found in plant-sources:
  • Mushrooms (grown in UV light)
  • Fortified foods
  • Dietary supplements

4. Who is at risk for Vitamin D deficiency?

• Breastfed Infants
• Elderly
• Obesity
• People who have had gastric bypass surgery
• Kidney Disease
• Liver Disease
• Lack of sun exposure depending on age, sunscreen use, geographical location

5. What are some signs of Vitamin D deficiency?

Vitamin D deficiency can be hard to diagnose based on symptoms. I don’t know about you, but I am tired all of the time and have had mood changes for the last four years with being pregnant and nursing. To diagnose low vitamin D your doctor can recommend a blood test to see where your level is at.

Signs of Vitamin D deficiency include:

• Fatigue
• Bone pain
• Muscle weakness, muscle aches/cramps
• Mood changes (depression)

6. Vitamin D needs to be converted into an active, usable form before the body can use it.

Taking a vitamin D supplement or getting it from your diet provides inactive vitamin D. Your liver and kidneys convert vitamin D to an active, usable form for your body. That is why people with liver and/or kidney disease are usually vitamin D deficient. 

7. Are both Vitamin D2 and D3 equally effective?

No, they are not. Although both are absorbed equally into the body, the liver converts them a little differently. Vitamin D2 is converted to a less active form than Vitamin D3. Most studies have shown that D3 is more effective at raising vitamin D levels in your body compared to D2.

With that being said, vitamin D3 supplements are more readily available.

8. Why are there two different measurements on a Vitamin D bottle?

You may have noticed that some labels of Vitamin D, along with Vitamins A and E, have two different units of measure, international units (IU) and metric units (micrograms – um). This is because back in 2016 the FDA changed their labeling requirements on nutrition and supplement labels. All labels are required to show the dose in metric units (ex: micrograms), but do not have to show the dose in IU’s.

• 1 microgram = 40 international units

9. Over-the-counter supplements

Over-the-counter supplements are not regulated by the Food and Drug Administration (FDA) like prescription medications are. Prescription medications have to go through years of testing to ensure quality, safety, and efficacy. The FDA doesn’t test what is in supplements. Oftentimes herbal products contain more than what the label specifies.

When buying supplements look for the following on a label:

• National Sanitation Foundation (NSF)
• United States Pharmacopeia (USP)
• Natural Products Association (NPA)

As always, ask your friendly pharmacist for recommendations or help finding a trustworthy supplement. Also, ask your doctor for a recommended dose. Sometimes if someone’s vitamin D level is extremely low your doctor may prescribe a weekly, high dose vitamin d supplement for a few months before taking a lower, daily supplement.

Vitamin D is a fantastic vitamin that does wonders for your body and bone health. Getting your daily dose of vitamin D from the sun is great, but remember to lather on that sunscreen and wear a hat to prevent sun damage, aging, and possible skin cancer. After talking with your doctor and deciding if vitamin D supplements are needed, head over to your local pharmacy and talk with your pharmacist about safe, trustworthy vitamin D supplements. Always ask your doctor about an appropriate dose.

Disclaimer: As always this information is not meant to be medical advice, but to help educate you and give you resources. If you have any health related concerns please talk with your doctor about them.