Experts say vitamin D can decrease symptoms of the lung disease, but people should make sure they need more of the mineral first.

People with chronic obstructive pulmonary disease (COPD) can reduce some symptoms by taking regular doses of vitamin D.
That’s according to a new study published in the journal Thorax.
“Vitamin D has two important effects on the immune system that could explain why it reduces symptoms of COPD,” Adrian Martineau, PhD, clinical professor of respiratory infection and immunity at the Blizard Institute at the University of London and co-author of the study, told Healthline.
“It boosts immune responses to respiratory viruses that commonly trigger COPD attacks. It also dampens down harmful inflammatory responses, thereby accelerating recovery and potentially limiting damage to the architecture of the lung,” Martineau said.
Vitamin D has another benefit for people with COPD, said David G. Hill, MD, a pulmonologist with Waterbury Pulmonary Associates in Connecticut and a medical spokesperson at the American Lung Association.
“In COPD, it makes sense to look for vitamin D deficiency because people are at risk for osteoporosis, and they don’t want fractures on top of their lung disease,” Hill told Healthline.
Barbara Yawn, MD, chief science officer for the COPD Foundation, agreed.
“In addition to possible triggers for attacks, people with COPD are at increased risk of osteoporosis, and calcium and vitamin D may provide some help,” Yawn told Healthline.
How do you know if you need vitamin D?
Hill explained that without medical testing and a doctor’s assessment, it’s difficult to determine signs or symptoms of vitamin D deficiency, such as fatigue, muscle and back pain, and increased infections.
“You need to be tested,” said John Linnell, who has stage 4 COPD. He’s a patient advocate and the COPD Foundation’s state captain for Wisconsin.
Linnell shared his concerns about people with COPD seeing headlines about the study and rushing out to get vitamin D without understanding the full picture that taking it won’t help if you don’t have a deficiency.
“It’s true that probably 25 percent of people with COPD are low in vitamin D,” Linnell told Healthline.
“If you live in a northern climate, you’re more apt to be low because you’re not getting as much sunshine. If you usually stay indoors or are housebound, you’re not getting sunlight and you’re more apt to be low in vitamin D,” he said. “If you’re obese, you tend to be lower in vitamin D because it stores in fat and doesn’t circulate throughout your body.”
For Linnell, supplementation without a deficiency is, simply put, doing nothing more than “creating expensive urine.”
Vitamin D has many benefits for a number of health conditions, but there are some risk factors from overdoing it.
“Vitamin D toxicity is a risk,” Yawn said. “Serious vitamin D toxicity isn’t common, but it can elevate calcium levels and cause negative effects on the bone, muscles, and kidneys,” she said. “No one should take large doses of vitamin D without medical supervision. If vitamin D is taken, it’s seldom necessary to take more than 400 to 600 IU daily.”
Hill said that vitamin D is relatively harmless. Even if a person has adequate levels, he or she isn’t likely to be harmed by taking a vitamin D supplement.
“You’d have to go out of your way to overdose on it,” he said.
Hill agreed with the study’s findings that taking vitamin D when your levels aren’t low won’t be beneficial. People with COPD can reduce this risk by talking to their doctors and coming up with an appropriate treatment approach.
“COPD is different for everyone,” Linnell said. “Some people have more emphysema or chronic bronchitis. Some rarely have flare-ups. Others are hospitalized three or four times a year for attacks. COPD needs to be treated individually, and it’s important for people to sit down with their doctors to create a personalized action plan.”
Once people with COPD know if they have a vitamin D deficiency, they have a few options.
“The most effective method is light exposure,” Yawn said, “but this can be supplemented by foods with added vitamin D, such as milk and certain brands of orange juice, and if required, vitamin D tablets or a multivitamin that includes vitamin D in the appropriate amount.”
“Taking vitamin D tablets should be discussed with your doctor before buying them or taking advice from someone selling vitamin D outside of the pharmacy.”
When it comes to lack of exposure to sunlight or inadequate dietary intake, Hill said oral vitamin D supplementation is the best method. He also explained that people who are deficient may be advised to take a higher dose than what’s recommended on product labels.
“People typically take a higher dose of vitamin D for the first couple months, then they go down to a maintenance level once their vitamin D levels are normal,” Hill said. “This is because a person who’s deficient in vitamin D will likely continue to have inadequate levels due to lack of sun exposure and dietary intake.”
On the other hand, Linnell said he’s “not a big vitamin person.” His approach is to uncover the reason for the underlying the deficiency and try to fix that first.
“Two things come to mind: Am I low in vitamin D and do I need this? And if so, why?” he said. “Does it automatically mean I need a supplement? Maybe I need to lose some weight because it’s being stored in my fat. Maybe I need to get outside and be more active, which could help in a number of ways.”