Vitamin D Supplementation. By Our Student Pharmacist, Paul Matheke.
A Guide to Vitamin D Supplementation
- Vitamin D is important for your bone health. Together with calcium, Vitamin D helps protect older adults from osteoporosis.[2] Most people do not consume enough vitamin D from their diet alone. That is why you may want to use a vitamin D supplement, especially if your vitamin D levels are running low.
- Vitamin D has evidence suggesting it to be effective with:
- Helping treat bone disorders.
- Helping prevent osteoporosis.
- Helping reduce the risk of multiple sclerosis. [3]
- Vitamin D is also being studied to assess its impact on cognitive health and preventing certain cancers. [3]
- If you are older than 70 your skin may not create vitamin D as efficiently as it used to. [2]
- In foods and dietary supplements, vitamin D comes in two forms:
- Vitamin D2 (ergocalciferol)
- Vitamin D3 (cholecalciferol)
- These two forms differ only slightly in their chemical structure.
- Both are safe and effective, however, some studies show that vitamin D3 is a bit more effective at raising and maintaining your vitamin D levels. [4]
- When you go to the doctor and they perform tests that can measure your vitamin D, here is what to look for:
- 25(OH)D is your vitamin D level. [2]
- These charts help you interpret your vitamin D levels and how much vitamin D you need every day.
- Not many foods naturally contain much vitamin D. Foods with some natural sources of vitamin D include:
- Fish (trout, salmon, tuna)
- Egg yolks
- Some mushrooms [2]
- Some foods, like milk, may be fortified to have vitamin D in them.
- Milk usually contains 120 IU/cup. [2]
- Of course, you also get vitamin D from the sun.
- The sun emits UV radiation that your skin uses to make vitamin D.
- However, depending on your location, the season, and how much time outside you spend, you may not get enough vitamin D from the sun alone–especially not here in Ohio!
- If you decide to get more time in the sun, make sure you wear enough sunblock! [2]
- If you decide that you want to use a vitamin D supplement, you should always consult with your doctor and pharmacist first.
- You have quite a few options with dosages of Vitamin D, as many brands provide different strengths and formulations.
- Dosages for the prevention of osteoporosis are typically in the range of 600-1,000 units.
- You may see higher doses, some as high as 4,000 units.
- You could take these doses, but be sure to get your vitamin D levels monitored as these are higher doses.
- Can I take too much vitamin D?
- Yes! And it could cause high calcium levels that hurt your bones and kidneys. [2]
- Fortunately, even if you take the highest doses available over-the-counter, like 4,000 IU daily, this is not a serious concern. Still, you should always keep your doctor in the loop about your supplementation and monitor your vitamin D levels to prevent excessive amounts.
- Symptoms of excessive vitamin D toxicity and high calcium are
- Confusion
- Fatigue
- Weakness
- Nausea and vomiting [5]
- Supplementation tips with vitamin D:
- Vitamin D can be taken with or without food.
- However, it is best taken with a meal, as this helps absorption. [5]
- Drug interactions with vitamin D
- Vitamin D can increase your risk of high calcium when taking a diuretic such as hydrochlorothiazide. [5]
- Vitamin D can be taken with or without food.
- You have quite a few options with dosages of Vitamin D, as many brands provide different strengths and formulations.
References:
[1] Pazirandeh S, Burns D. Overview of Vitamin D. UpToDate. September 23, 2021. Accessed November 15, 2021. www.uptodate.com
[2] NIH Health Information. Vitamin D. Accessed November 15, 2021 https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
[3] Mayo Clinic. Vitamin D. Accessed November 15, 2021. https://www.mayoclinic.org/drugs-supplements-vitamin-d/art-20363792
[4] Harvard University: The Nutrition Source. Vitamin D. Updated March, 2020. Accessed November 15, 2021. https://www.hsph.harvard.edu/nutritionsource/vitamin-d/
[5] Lexi Drugs: Ergocalciferol. Wolters Kluwer. Accessed November 15 2021. online.lexi.com.