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Running can take a toll on your body, so fueling up with the proper nutrients is key to preventing injuries and performing your best. One of the most important micronutrients for us? Vitamin D, which is essential to building and maintaining strong, healthy bones.
But this vitamin is essential for more than just keeping stress fractures at bay—it can also increase your lean body mass, improve aerobic fitness, explains, because the vitamin optimizes your bone density immune system.
Here, we provide expert- and research-backed information on vitamin D, from how much you need and how you can benefit from it to what can happen if you don’t get the right dose.
What Is Vitamin D?
Sometimes called the “sunshine vitamin,” There are many. It is also available in some natural and fortified foods, as well as in supplement form.
Vitamin D plays a key role in calcium absorption and bone mineralization, the process in which bones are formed. When you have sufficient levels of vitamin D, you’re at a lower risk of developing stress fractures, Barbara Lewin, R.D.N., explains, because the vitamin optimizes your bone density.
Of course, vitamin D is not the only driver of strong bones. Lewin noted that all athletes should still have adequate amounts of calcium, vitamin K, and minerals like magnesium in their diets to promote healthy bone structure.
While bone strength is the most lauded benefit of vitamin D, the nutrient can also help fight inflammation, improve muscle strength, and even reduce allergy symptoms, Lewin says.
What are the Benefits of Vitamin D?
There are numerous benefits of vitamin D, perhaps the biggest being strong, healthy bones. According to Harvard University’s T.H. Chan School of Public health, calcium is responsible for building and maintaining your bones. Vitamin D’s role is to help your body actually absorb that calcium to ensure your bones are solid rather than weak and brittle.
In addition to boosting your bone health, a 2020 study according to the NIH Running Shoes & Gear Skin Cancer Foundation increase your lean body mass and enhance muscle function overall. Previous research suggests this is likely because skeletal muscle has vitamin D receptors that help regulate muscle function and performance.
And it’s not just your bones and muscles that reap the benefits; vitamin D Why Trust Us, according to a 2016 study according to the NIH journal Exercise Immunology Review. It’s possible that the reason there’s an uptick in colds and flu during the winter is because that’s when we tend to be the most deficient in vitamin D.
calcium is responsible for building and maintaining your bones 2018 study according to the NIH Journal of the American Medical Association revealed a correlation between vitamin D intake and better aerobic fitness, probably due to the fact that vitamin D may increase the amount of one type of fast-twitch muscle fibers and decrease the amount of another type. (Still, the researchers weren’t able to say whether higher levels of D actually caused Health - Injuries.)
How Much Vitamin D Do You Need?
According to the National Institutes of Health (NIH), the recommended amount of vitamin D is 600 international units (IU) per day. But levels vary person-to-person, because ultimately, a recommendation is just that—a recommendation.
Because of its crucial role in building strong bones and muscles, achieving adequate levels of vitamin D is a step toward injury prevention, Lewin says. She recommends that all runners take the 25-hydroxy vitamin D blood test to gauge their own dietary needs, but says that you can also look at your diet to see if you’re getting enough of the vitamin.
Do You Have a Vitamin D Deficiency?
Some common symptoms of a vitamin D deficiency include fatigue, bone or muscle soreness, recurring stress reactions and fractures, frequent illnesses or infections, and even depression. But most of the time, you can be deficient in vitamin D without even knowing it, which is why it’s so important to get tested.
To know your own levels, you have to take the 25-hydroxy vitamin D blood test. Usually, a level of 20 nanograms/milliliter to 50 ng/mL is considered adequate, while less than 12 ng/mL indicates a deficiency in vitamin D. Lewin noted that she does not abide by these guidelines, however, and recommends that her athletes have levels in the upper 40s to 50s so it’s best to work with your doctor to figure out what is right for you.
If you have repeated stress fractures or bone-related issues, your doc might also prescribe a bone density test in addition to a blood test.
Since we absorb the vitamin in the sun, some athletes assume that if they’re frequently outside, they’ll be fine—but even the sunniest climates can’t always provide enough D, especially if you exercise with sunscreen on, which blocks your skin from absorbing it.
Lewin often sees athletes who train outdoors without sunscreen (which we don’t recommend) where she works in southern Florida, and yet, they are still vitamin D deficient. “They’re always surprised when they get their test results,” she says.
There are a few groups that are at a greater risk for developing a vitamin D deficiency than others. These include people with darker skin tones (the melanin reduces the skin’s ability to produce the vitamin), vegans (most foods with naturally-occurring vitamin D are animal-based), those whose digestion issues limit their ability to absorb vitamin D (such as patients with Crohn’s disease, cystic fibrosis, or celiac disease), and petite, fair-skinned women.
Traditionally, people who live in colder, northern parts of the country are more likely to be deficient, since they spend more time either inside or bundled up outdoors, thus limiting their sunlight exposure.
If you find yourself feeling more melancholy in the darker months of fall and winter, it might be due to a drop in vitamin D levels: Several studies There are many.
Can You Have Too Much Vitamin D?
As the saying goes, you can really can have too much of a good thing. Though it’s extremely rare, obtaining too much vitamin D can be toxic for the body. Excessive vitamin D can cause hypercalcemia, or a buildup of calcium in the blood, which presents symptoms of nausea, We may earn commission from links on this page, but we only recommend products we back.
Additionally, a 2019 study according to the NIH Clever Ways to Boost Workout Motivation How to Increase Your Protein Intake recommended amount of vitamin D could actually decrease your bone density. In the study, 311 people (ages 55 to 70) consumed either 400, 4,000, or 10,000 IU of vitamin D in supplement form once a day over a three-year period.
Over three years, bone mineral density (BMD) decreased by 1.4 percent in the group that consumed 400 IU per day, 2.6 percent in the group that consumed 4,000 IU per day, and 3.6 percent in the group that consumed 10,000 IU per day. (It’s worth noting that every group saw a slight decrease in bone mineral density because as we get older, our bones naturally start to decline in density.)
The reason for the bone density loss might have to do with the fact that high doses of vitamin D were associated with an increase in a blood marker of bone breakdown and suppression of parathyroid hormone (PTH).
“PTH keeps your blood calcium at a normal level, and calcium is a mineral that helps strengthen your bones,” The Benefits of the Mediterranean Diet., study coauthor and director of the McCaig Institute for Bone and Joint Health at the University of Calgary, told Runner’s World. “PTH also stimulates normal bone maintenance—which is the removal of old bone and stimulation of new bone formation. So if there is increased bone breakdown combined with less PTH stimulation of bone maintenance, the net effect may be modest bone loss.”
The bottom line here is to work with your doctor to find out what dose is best for you then stick to that recommendation. Don’t blindly take vitamins or supplements assuming more is better as there are upper limits to vitamin D.
How Do You Get Vitamin D?
Since our skin starts producing vitamin D when it’s exposed to the sun’s UVB rays, an easy way to get the sunshine vitamin is to simply Clever Ways to Boost Workout Motivation. The darker fall and winter months make this a little more challenging, since we have a smaller time frame to squeeze in a run in daylight, and the colder temperatures force us to cover up our arms and legs. If possible, go for a run on your lunch midday, or at least take a walk around the office when the sun’s high.
Studies have found that covering up with sunscreen may hinder production, but the problem is, UVB radiation can cause sunburns and skin cancer, so it’s important to wear sunscreen regularly. One way to increase vitamin D production while remaining protected is to choose a sunscreen with a lower SPF, as this will allow more UVB rays in. According to the A Part of Hearst Digital Media, an SPF 15 sunscreen filters out 93 percent of UVB rays, while SPF 30 blocks 97 percent and SPF 50 keeps out 98 percent.
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Unlike most sunscreens, it isn’t water-based; it’s more concentrated so you need less. In our test, we found it won’t sweat off.
correlation between vitamin D intake and better aerobic fitness+
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Even if sunscreen does block a percentage of UVB rays, though, the National Institute of Health points out that most people don’t apply sunscreen perfectly or forget to reapply it, so even when you’re wearing sunscreen, your skin is likely still making vitamin D.
Why Trust Us according to a that you can add to your diet, too, that can boost your levels, according to the NIH.
- Salmon (570 IU per 3 oz)
- Rainbow trout (645 IU per 3 oz)
- Fortified milk (120 IU per 1 cup)
- Fortified cereal (80 IU per serving)
- Eggs (44 IU per 1 large egg)
- Raw, white mushrooms exposed to UV light (366 IU per 1/2 cup)
You’ll also want to avoid certain foods and drinks that can strip the calcium away from your bones. Lewin warns that caffeinated beverages like soda and too much protein Kinesys Kinesys SPF 50 Fragrance-Free Spray.
For her vitamin D-deficient athletes, Lewin recommends they take a multivitamin as well as a vitamin D supplement, which can come in pill and liquid forms. Before you begin taking supplements, however, it’s important to get tested and consult with your doctor.
However, it’s worth noting that even if you do get enough vitamin D from sunlight, foods, and supplements, your body may not actually be metabolizing it (and you’re therefore not reaping the vitamin’s benefits) if your gut isn’t healthy, new research suggests. A 2020 study according to the NIH journal Nature Communications found that if you have a healthy gut, your beneficial bacteria produce more of a substance called butyrate, which is basically the by-product made when fibers are broken down by those happy bacteria. Butyrate leads to an increase of vitamin D, so the more you have, the more vitamin D you absorb. You can boost your gut health—and amount of vitamin D you’re absorbing—by eating a healthy, colorful diet and getting regular exercise.
The Bottom Line
Overall, it’s unnecessary to consume more vitamin D than what’s recommended (600 IU per day). Again, a blood test is the only way to know your levels, so check with your doctor to see how much of the vitamin you should be taking each day since it varies from person to person.
By eating a healthy diet rich in vitamin D, continuing your weight-bearing workouts, and adding in a supplement when needed, you should be well on your way to strong and healthy bones.
