I'm A Registered Dietitian & This Is The Biggest Nutrition Myth I See All The Time
At team mbg, we're always happy to pop our food and nutrition questions over to our director of scientific affairs Ashley Jordan Ferira, Ph.D., RDN (who welcomes all of our ruminations with open arms, we should add!). What's up with the new Dietary Guidelines for Americans? What's the deal with vitamin K2? What's the best form of zinc to take? And most recently: Are there any nutrition myths you see online that make you cringe?
"Most of the myths I see have to do with vitamin D," she says with zero hesitation on the mindbodygreen podcast. Let's debunk the coveted nutrient, shall we?
The biggest myth about vitamin D, explained.
Vitamin D is one of the most well-documented players for immune support—an "old-school" nutrient, if you will.* However, it skyrocketed in popularity this past year, after cross-sectional studies found vitamin D deficiency was higher in COVID patients than the control groups. As such, vitamin D finally got the recognition it deserves—although, says Ferira, it's important to truly digest what you're reading online.
"We're all deficient in vitamin D," says Ferira. She states that 92.5% of Americans don't even get 400 IU a day of vitamin D in their diet, whereas "we actually need a minimum of 2,000 to 3,000 IU daily," so you do the math. A huge gap—and yet, most health media outlets provide a single solution: Eat vitamin-D-rich foods.
"That's a huge myth that I'd like to bust," Ferira notes. (She explains her reasoning further, in case you're curious). "Telling someone to meet their vitamin D requirement through food is like giving you a quart of paint to go repaint your entire house."
Vitamin D is naturally found in small amounts in a handful of foods—which are helpful for preventing extreme vitamin D deficiency and related ailments like rickets or osteomalacia. For example, 1 cup of milk contains 100 IU of vitamin D. But when it comes to ramping up and maintaining healthy vitamin D status for life, those modest intake levels alone just won't cut it.*
What to do about it.
Daily immunity shield to strengthen your body’s natural defenses*
Sufficient blood levels of 25(OH)D, the measure of vitamin D status, are considered to be greater than 20 to 30 ng/mL. As Ferira explains, "In fact, those are the cutoffs for vitamin D insufficiency/deficiency so not goals to aim for but rather minimums to avoid."
To consistently achieve a 25(OH)D blood level greater than 30 ng/mL, research shows you need a minimum of 2,000 to 3,000 IU of vitamin D3 every day. That's because 100 IU of vitamin D3 daily raises your 25(OH)D level by about 1 ng/mL. Ferira adds, "By the way, this rule-of-thumb applies to individuals with a healthy weight; those struggling with overweight or obesity will need two to three times more vitamin D3 daily." You can now see why it's pretty difficult to get through food alone.
That's why Ferira is a fan of targeted daily supplementation for vitamin D3 specifically: She personally takes 5,000 IU vitamin D3 softgels every day, but she also touts a high-quality multivitamin and daily immune-centric supplement as a great way to simultaneously get your fill of other critical nutrients you may be missing.* "Talk about filling the gaps—that's a strategic way to do it," she says.*
"I'm glad that the pandemic brought micronutrients like [vitamins] C, D, and zinc back to the forefront," says Ferira. But we do have to be smart about what we read and/or hear through the grapevine. When it comes to vitamin D, getting sufficient levels oftentimes takes more than fridge staples.*