Of course it’s easier to expose yourself to natural UV light from the sun during the summer when the days are long and the weather is more conducive to outdoor living. Whereas in the wintertime (depending on where you live), UV rays are seriously lacking, and everyone tends to hole up and hibernate inside—an inclination that makes it even harder for your body to get the vitamin D it craves. “Limited exposure to sunlight may lead to lower levels of active vitamin D that contributes to a healthy immune system,” says Mike Roizen, M.D., chief wellness officer at Cleveland Clinic and author of What to Eat When, who emphasizes how vital it is to get enough vitamin D—and generally find ways to support your immunity—all year long. While sunlight exposure is the most commonly thought of source of active vitamin D—it’s essential for turning the vitamin D produced by humans into active vitamin D2/3, Dr. Roizen explains—you can also find active vitamin D in healthy, accessible foods. Below are the five best vitamin D–rich foods you should be eating in every season, according to diet and nutrition experts, plus how to add them into your regular snack and meal rotation.
Vitamin D Foods
“I like adding herbs and spices to salmon and baking it to eat as a main dish or flaked with some breadcrumbs, egg, and chopped veggies to form a salmon burger patty,” says Berman. “Vitamin D is a fat-soluble vitamin that’s needed to maintain healthy bones,” Berman adds. “Its primary function is to absorb calcium and phosphorus during digestion. Calcium is the mineral needed to support bone health and proper nerve and muscle function.”
How Much Vitamin D Do You Need?
The National Institutes of Health (NIH) recommends that most adults consume between 600 to 800 IU of vitamin D per day, which is the Recommended Dietary Allowance (RDA). Berman agrees, adding that experts recommend getting about 600 IU. And though several foods—like salmon, eggs, and even fortified orange juice—are all common sources of vitamin D, many of us still don’t meet the recommended daily amount for optimal health. According to the NIH, data analysis from the 2015–2016 National Health and Nutrition Examination Survey (NHANES) found that the average daily intake of vitamin D was only 204 IU for men and 168 IU for women. “An issue for some of us is that there aren’t tons of foods that naturally contain vitamin D,” says Lewis. “To put this into perspective, 3 ounces of salmon contains 447 IU, a cup of milk contains 124 IU, and an egg contains 41 IU. Clearly, it’s not easy to reach the 600-800 IU recommendation every day, and most Americans do not get enough vitamin D through food alone.”
Vitamin D Deficiency
According to Lewis, long-term vitamin D deficiency can lead to osteomalacia (softening of the bones), which can cause symptoms of bone pain and muscle weakness. “The issue with these symptoms is they can be due to many different factors and/or can go unnoticed and undetected for a long period of time,” she adds. “Insufficient vitamin D intake is also associated with osteoporosis, cardiovascular disease, cognitive decline, diabetes, and various cancers.”
Do You Need a Vitamin D Supplement?
It’s fairly common for people to consider a vitamin D supplement—or for their doctor to recommend one—in order to meet their needs. But figuring out your body’s personal requirements for this vitamin is tricky. “What’s considered an optimal level of vitamin D is something of a controversy,” Lewis explains. “Some medical institutions think vitamin D deficiencies have been overestimated, while others feel they’ve been underestimated when it comes to the American population.” According to Lewis and Dr. Roizen, we should all be prioritizing healthy food sources to reach our vitamin D needs, whether or not we’re spending a sufficient amount of time outdoors. That said, if you find you’re still deficient, you may want to chat with your doctor and consider a vitamin D supplement, especially in winter months and when spending a surplus of time inside in isolation. However, neither expert recommends supplementing blindly; there’s a wide range of doses to choose from and the dose should be dependent on your baseline level, and how far away you are from the normal blood level range. The best starting place is getting a vitamin D test done to assess your baseline level prior to taking a supplement. This is especially helpful to do in the wintertime when levels tend to be lowest for Americans. Depending on your medical history and vitamin D levels in your blood, your doctor may recommend a vitamin D supplement. The dose you’ll need to maintain healthy blood levels depends on your diet, genetics, body size, and additional lifestyle factors.
