Vitamin D is best known for helping keep bones strong, but it also plays an important role in the immune system.
Scientists have been studying whether this vitamin could also affect inflammatory diseases, including inflammatory bowel disease (IBD), a long-term condition that causes inflammation in the digestive tract.
IBD mainly includes two illnesses: Crohn’s disease and ulcerative colitis. Both conditions can cause stomach pain, diarrhea, weight loss, tiredness, and other symptoms that often come and go. Although medicines can help control the disease, many people still experience flare-ups, making it important to find other ways to support treatment.
A new study suggests that vitamin D levels may be closely linked to how much inflammation people with IBD have. The research was led by Dr. Antonia Topalova-Dimitrova from the University Hospital St. Ivan Rilski and the Medical University in Sofia, Bulgaria.
The researchers compared 92 people with inflammatory bowel disease with 14 healthy volunteers. They measured vitamin D levels in the blood and also checked several markers that show how much inflammation is present in the body.
The results showed that people with IBD had much lower vitamin D levels than healthy participants. On average, people with IBD had vitamin D levels of 16 nanograms per milliliter, compared with 26 nanograms per milliliter in the healthy group.
Vitamin D deficiency was very common among the patients. About one-third of people with IBD were deficient, while another two-thirds had vitamin D levels that were lower than recommended. Most healthy participants, on the other hand, had normal vitamin D levels.
The study also found that lower vitamin D levels were linked to higher levels of inflammation. People with less vitamin D tended to have higher white blood cell counts and higher levels of C-reactive protein, or CRP, a blood marker that doctors often use to measure inflammation.
These findings suggest that vitamin D may play a role in helping control inflammation. However, the researchers stressed that the study only found a link between the two. It does not prove that low vitamin D directly causes inflammation or that raising vitamin D levels will cure IBD.
Previous research has also shown that people with IBD who have low vitamin D levels are more likely to have disease flare-ups, respond more slowly to treatment, and may even be more likely to need surgery. Because of this, checking vitamin D levels has become an important part of care for many patients.
People can increase their vitamin D through foods such as oily fish, eggs, and fortified dairy products, by getting safe sunlight exposure, or by taking vitamin D supplements. For many people with IBD, supplements may be the most practical choice because some medications or skin problems can make spending time in the sun more difficult.
The researchers say more studies are needed to learn whether improving vitamin D levels can reduce inflammation and improve long-term health in people with IBD. If future studies confirm these benefits, vitamin D could become an even more valuable part of managing Crohn’s disease and ulcerative colitis alongside standard treatments.
The study was published in the journal Medicine.
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