This Is How Much Vitamin D You Really Need Every Day

Vitamin D is essential to our health and existence, but depending on where you live or what you do for a living, you might not be getting enough of it. Though we know it's a fundamental part of our well-being, what most of us really know about the nutrient is relatively limited. How can we be sure we're getting our daily dose? New York Magazine's Science of Us recently consulted two experts to weigh in on just how much vitamin D is actually needed.

Vitamin D is a "uniquely important vitamin" because it controls hundreds of genes and is involved in the endocrine system and immune system, says Chris D'Adamo, PhD, an assistant professor at the University of Maryland School of Medicine. He also notes that the main way people get vitamin D is through sun exposure, which registered dietitian Brigitte Zeitlin adds is like "human photosynthesis." The average recommended daily dose for adult males and females is 600 IU (15 micrograms), or 10 to 15 minutes of uncovered sun exposure.

You can also up your vitamin D intake through certain foods like salmon, tuna, and sardines, as well as fortified milk. Being sure to spend some time outdoors each day and eating a well-rounded nutrient-packed diet are the best ways to ensure you're getting enough vitamin D, but the only way to know for sure is through a blood test (which you'll likely get during your annual physical). Individuals with vitamin-D deficiencies don't often have symptoms, though they can experience fatigue, muscle aches, and migraines. D'Adamo recommends geting a vitamin-D test to be sure.

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