Vitamin D decoded: latest insights on vitamin D testing and supplements
Emily Faltemier, MD, is a primary care physician board certified in family medicine who specializes in pediatrics, women’s health and primary care for adults. Dr. Faltemier sees patients at Family Medicine of Clifton/Centreville.
Have you ever wondered why sunshine makes you feel so good? It’s not just the light of the day or the warmth on your skin —it’s the boost of vitamin D. Known as the “sunshine vitamin,” this essential nutrient plays a vital role in keeping your bones strong, your immune system robust, and your mood elevated. As the days get shorter and we see less of the sun, it’s important to ensure you’re getting enough vitamin D. Whether it’s through your diet, supplements, or a few minutes of sun exposure, there are several ways to harness the power of this vitamin to help improve and maintain your overall health.
How can I boost my vitamin D?
During the winter months, when sunlight is scarce, you can turn to certain foods for extra nutrients, including: Fatty fish such as salmon, tuna and sardines
- Cereal, yogurt, milk, almond milk and orange juice (look for products fortified with Vitamin D)
- Eggs
- Beef liver
- Spinach
- Bananas
Spending more time in the sun for short periods without sunscreen — 10 or 15 minutes three or four days a week — can boost your vitamin D as well. It really does matter where you live, the time of day you go out and the time of year. In winter, you’re all covered up and your skin has less contact with the sun. In the summer, it is important to protect yourself when you’re outside in the sun for longer periods of time. Use sunscreen that has a minimum of SPF 15, along with high-SPF clothes, hats and sunglasses.
Who should be tested for vitamin D deficiency?
The United States Preventive Services Task Force (USPSTF) looks at studies and evidence to support its recommendations for certain preventive screenings and tests. The USPSTF does not recommend screening the general population for vitamin D deficiency because there is not enough evidence to support routine screening recommendations. The USPSTF does recommend screening for people at higher risk of vitamin D deficiency.
People who are at higher risk of vitamin D deficiency and who should be tested include:
- Individuals who have a body mass index higher than 30
- Women who are pregnant
- People with conditions such as chronic kidney disease, osteoporosis, inflammatory bowel disease, cystic fibrosis or celiac disease
Most insurance plans don’t cover the cost of a vitamin D test unless there is a medical need. If a patient without a medical need requests a test, Inova will provide a form that details the cost and how it’s managed through their health insurance.
Current guidelines for vitamin D supplements
The current guidelines are 600 international units (IU) daily for those ages 1 to 70 years and 800 IU daily for those over 70 years old.
When are vitamin D supplements recommended?
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Vitamin D supplements are recommended for individuals who:
- Show a deficiency, including pregnant and breastfeeding mothers
- Have trouble absorbing the vitamin, especially older adults
- Need treatment for osteoporosis
- Don’t get enough sun
- Have chronic kidney disease
- Have been diagnosed with obesity
How are vitamin D2 and D3 different?
Both vitamin D2 and D3 supplements will improve your vitamin D level. Vitamin D2 is only available by prescription, and can be prescribed when a patient’s levels are very low. Vitamin D3 is available over the counter and is more cost effective. It may also be better absorbed in the intestinal tract.
Vitamin D safety and side effects
Taken in recommended doses, vitamin D is considered quite safe, but taking too many supplements — anything in excess of 4,000 IU daily — may be harmful. Vitamin D is a fat-soluble vitamin, so it is not quickly passed through the body if you have too much. More is not always better and potential side effects include:
- A buildup of calcium, resulting in kidney stones or effects on the parathyroid hormone
- Heart rhythm issues
- Nausea and vomiting
- Weight loss
- Weakness
Vitamin D can help prevent and manage chronic disease
Individuals who are affected by osteoporosis or inflammatory bowel disease may benefit from supplements, but research has not clearly shown that taking vitamin D reduces the risk of chronic disease.
Obvious signs and symptoms of vitamin D deficiency
Not many people in the overall population are actually vitamin D deficient. However, most people who are deficient in vitamin D don’t show any signs or symptoms. If signs do appear, they may include:
- Significant fatigue
- Weakness
- Leg pain
- Aching bones (severely deficient)
If you are experiencing these symptoms, talk to your provider about whether you should consider increasing your vitamin D intake.
Schedule an appointment
Inova Primary Care offices offer appointments in the office and virtually. To set up a time to talk with your doctor, schedule an appointment through your MyChart patient portal, book an appointment online or call your doctor’s office.
Vitamin D in the correct amounts also helps the liver process fats. NIH research shows that to low or too high levels contribute to fatty liver.
I have developed a better understanding of Vitamin D than my general practitioner. Went thru a year of testing, prodding, poking, scans, etc. to be deficient.
I suggest you search Ninja Nerd Association Between Vitamin D Deficiency, learn how Vitamin D is created, and how the lack of it creates inflammation. You may start to think of (4) years ago. If one understands the Macrophages which increase Cathelicidins to cleave virus cells, help T-Cells turn into TH2 cells to produce TH4 & 5 to produce B-Cells to produce Plasma cells which produce antibodies which binds to compliment system, enhance the phagocytosis process, and bind to virus receptors. This anti-inflammatory reverses itself without Vit D and releases IL-10 which produces massive inflammation.
I would also suggest when a person has an aliment or condition, search condition vitamin D deficiency. You will be amazed at the studies in NIH related to most subjects.
You know more D is need than remediation, but I also understand if you recommend more you open yourself up to liability and, more importantly, scrutiny from Big Pharma and hospital leadership.
Haven’t felt this good in 10 years….
Article is Ok for 95% of individuals. It fails to mention optimal levels(think lifeguards and roofers) and is absent in mentioning those groups that do not metabolize D3 in sunlight(NHS study of 2017, vitamin deficiency in sub-genetic groups, University studies show that 65% of the Scot and UK population with red hair is affected)
How important is K2 with Vitamin D as I heard it increases the level of Calcium in the blood
This article covered salient points and was helpful. Thank you.
What time of day is best to take vitamin D? Can vitamin D interfere when taking other medications?
Loved reading your info on Vit D! So insightful! Thank You