How Much Vitamin D Per Day Is Recommended?
According to the Institute of Medicine (IOM), the recommended dietary allowance for vitamin D is 15 mcg per day (or 600 International Units, aka IU) for men and women over 18. For older adults ages 70 and older, the recommended amount of vitamin D is set a little higher, at 20 mcg (or 800 IU). (3)
FYI: The amount of vitamin D can be expressed in micrograms or International Units (IU). One microgram of vitamin D is equal to 40 IU—so 10 micrograms of vitamin D would equate to 400 IU.
That said, recent research suggests higher doses may be helpful in supporting vitamin D levels—particularly for those of us experiencing those previously-mentioned lifestyle factors, or have darker skin—which is why we include 2,000 IU of vitamin D3 in our multivitamins.* (4)
Is Vitamin D Supplementation a Good Idea?
The short answer: Even if you live somewhere with plenty of rays, it’s certainly a smart way to shore up any gaps—especially when you consider national data, which shows that approximately 65% of us don’t get enough Vitamin D from diet and sun exposure combined.* (5)
Here’s the thing: Very few foods naturally contain vitamin D, much less in high dosages. The best sources of vitamin D are found in the flesh of fatty fish (salmon, trout, tuna, mackerel, sardines) and fish liver oil. Beef liver, egg yolks, cheese, and mushrooms also contain vitamin D in varying amounts. (3)
But incorporating vitamin D-rich foods—in the amount needed to meet optimal levels of vitamin D—is not as easy as it sounds: You’d have to eat a pretty considerable amount daily, and even then, it may not be a guarantee. “There can be variation depending on the type of salmon,” points out Dr. Michelle Davenport, PhD, a registered dietitian and member of Ritual’s Scientific Advisory Board. “Farmed salmon may contain as little as 25% of the D3 typically found in wild salmon.”* (6)
→ Essential reading: Vitamin D and Pregnancy: Here’s What to Consider