Vitamin D is best known for helping the body build strong bones and teeth, but scientists are learning that this important nutrient does much more than that.
It also helps the immune system work properly and may play a role in controlling inflammation. A new study has added to growing evidence that vitamin D could be especially important for people living with inflammatory bowel disease, often called IBD.
The research was published in the journal Medicine and was led by Dr. Antonia Topalova-Dimitrova from the University Hospital St. Ivan Rilski and the Medical University in Sofia, Bulgaria. The researchers found a strong connection between low vitamin D levels and higher levels of inflammation in people with inflammatory bowel disease.
Inflammatory bowel disease is not a single illness. It mainly includes Crohn’s disease and ulcerative colitis. Both are long-term conditions that cause the body’s immune system to attack parts of the digestive system by mistake. This leads to ongoing inflammation that can damage the intestines.
People with IBD often experience stomach pain, diarrhea, tiredness, weight loss, poor appetite, and sometimes bleeding. Symptoms may improve for a while and then suddenly return during what doctors call a flare-up. Living with IBD can affect work, school, family life, and mental health.
Vitamin D comes from sunlight, certain foods, and dietary supplements. Fatty fish, egg yolks, fortified milk, and fortified breakfast cereals are common sources. After vitamin D enters the body, it helps control calcium levels for healthy bones. Scientists now know that vitamin D also affects many immune cells, which has raised interest in whether it can influence inflammatory diseases.
To explore this question, the researchers studied 92 people with inflammatory bowel disease and compared them with 14 healthy volunteers. Blood samples were collected to measure vitamin D levels as well as markers that show how much inflammation was present in the body.
The results showed a large difference between the two groups. People with inflammatory bowel disease had an average vitamin D level of only 16 nanograms per milliliter, while healthy participants averaged 26 nanograms per milliliter.
More than 98 percent of the people with IBD had vitamin D levels that were either too low or clearly deficient. Around one-third had a vitamin D deficiency, while about two-thirds had levels that were below the recommended healthy range. In comparison, more than one-third of the healthy volunteers had normal vitamin D levels.
The researchers also discovered that lower vitamin D levels were linked with higher levels of inflammation.
People with less vitamin D tended to have higher white blood cell counts and higher levels of C-reactive protein, a blood marker that increases when inflammation is present. This pattern suggests that vitamin D may be closely connected with disease activity in inflammatory bowel disease.
It is important to understand what this study can and cannot show. This was an observational study. That means the researchers found a relationship between vitamin D and inflammation, but they could not prove that low vitamin D directly causes inflammation or makes flare-ups happen.
It is also possible that people with more severe disease develop lower vitamin D levels because their damaged intestines absorb nutrients less effectively or because they spend less time outdoors.
Even so, the findings are important because vitamin D deficiency is already common among people with inflammatory bowel disease. Poor nutrient absorption, reduced food intake, less sunlight exposure, and some medicines may all contribute to lower vitamin D levels.
Earlier studies have also suggested that low vitamin D may be linked with a greater chance of disease relapse, a weaker response to some biologic medicines, and a higher risk of surgery.
Although more research is still needed, checking vitamin D levels may become an important part of routine care for many people with inflammatory bowel disease.
If levels are low, doctors may recommend eating more vitamin D-rich foods, spending safe amounts of time outdoors, or taking vitamin D supplements. People should not start high-dose supplements without medical advice because too much vitamin D can also be harmful.
This study adds to the growing understanding that vitamins are not only important for preventing deficiencies but may also influence the way the immune system works.
For people living with inflammatory bowel disease, paying attention to vitamin D levels could become one simple step that supports overall treatment alongside medicines and regular medical care. Future studies will help scientists learn whether improving vitamin D levels can directly reduce inflammation and improve long-term health.
If you care about gut health, please read studies about how probiotics can protect gut health ,and Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
For more health information, please see recent studies about how food additives could affect gut health, and the best foods for gut health.
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