Crohn’s disease, a condition marked by inflammation in the lining of the digestive tract, can cause diarrhea, fatigue, weight loss and malnutrition, and affects an estimated 201 out of 100,000 American adults, according to the Centers for Disease Control and Prevention (CDC. While there’s no single treatment for Crohn’s disease (CD), and its exact causes are unknown, a study published Monday in the United European Gastroenterology journal suggests taking a daily vitamin D supplement may help prolong CD remission.

“For a long time, we’ve know that people with Crohn’s disease have a high risk of developing bone disease, like osteoporosis … there’s strong evidence now, including experimental work, that vitamin D affects the immune system and basically has anti-inflammatory effects,” senior study author Maria O’Sullivan, associate clinical medicine professor at the Trinity Centre for Health Sciences at St. James Hospital in Dublin, Ireland, told FoxNews.com.

Previous research has suggested that vitamin D may impact gut barrier function—determined in part by intestinal permeability— a factor thought to predict flare-ups and relapse from CD.

“It’s an interesting step if you could predict [CD] and reverse it, this could have a lot of therapeutic potential,” O’Sullivan said. The current pilot study is the first to use a randomized, placebo-controlled model to analyze vitamin D’s effect on gut barrier function, she added.

With first study author Tara Raftery, a PhD candidate at Trinity College Dublin, O’Sullivan recruited 27 study participants in clinical remission from CD. Thirteen patients received an active 2,000 IU vitamin D supplement and 14 patients received a placebo, and each group took two tablets every day for three months. Researchers collected the participants’ daily urine samples throughout the study period, and assessed their biomarkers associated with CD, inflammation, and gut barrier function at baseline and at the end of the study.

At the end of the study, Raftery and O’Sullivan saw reduced inflammation in patients who took the vitamin D supplement, and they observed that while intestinal permeability deteriorated in the placebo group, permeability levels were maintained in the supplement group.

“We saw the vitamin D group stayed the same; the ones who had the placebo got leakier guts. That’s why we’re clearly following this,” said O’Sullivan, who noted her team’s findings are limited due to the study group size and the three-month study period. “Anything in a small study needs to be approached with a degree of caution. It’s interesting for future work.”

O’Sullivan said her team has completed a follow-up interventional study examining vitamin D’s role in prolonging relapse from CD in 120 patients over a year, and they plan to announce their results in the next few months.

“I think from a clinic perspective, at the minimum we should be preventing deficiency. Beyond that, we can’t recommend it for treatment levels at the dose we used— we need to have a sufficient amount of evidence,” she said. “But we should be identifying deficiency and maintaining optimal levels [of vitamin D.]”

According to the Mayo Clinic, the recommended daily allowance (RDA) of vitamin D is 600 IU for healthy people ages 1 to 70 and pregnant or breastfeeding women, and 800 IU for people over age 71.  For osteoporosis patients, 100-200,000 IU of vitamin D2 or D3 is recommended by mouth daily or every two months for six months.