Surprising ways vitamin-D affects Crohn’s and colitis

Staying on top of your vitamin D levels is important when you have Crohn's disease, ulcerative colitis, or microscopic colitis. Vitamin D deficiency is associated with worse disease outcomes while normalization of vitamin D may help improve outcomes and quality of life. In this article, we cover some of the surprising ways that Vitamin D affects IBD.

What is vitamin D?

Vitamin D is an essential vitamin and nutrient that your body needs to promote calcium and phosphate absorption. Vitamin D is found in some foods and may be added to others (such as milk or juice) but is more readily accessible as a supplement. Your body naturally produces Vitamin D when exposed to sunlight. 

What is a vitamin D deficiency?

A vitamin D deficiency is when your body does not have enough of vitamin D to function properly which may lead to loss of bone density, osteoporosis, and fractures. Studies have reported that 30-40% of people with IBD may be deficient in vitamin D¹ and that approximately 68% of people are vitamin D deficient at diagnosis². Compared to healthy people, those with Crohn’s or colitis are 64% more likely to have a vitamin D deficiency³. 

What happens if you’re deficient in vitamin D?

In people with Crohn’s disease and ulcerative colitis, a vitamin D deficiency has been associated with⁴

• Longer duration of active disease
• Higher levels of certain tests that measure inflammation (fecal calprotectin, ESR, CRP)
• Increased pain
• Hospital admissions
• Trips to the emergency room
• Surgery

Who’s at risk of a vitamin D deficiency?

If you have any of the following characteristics, you may be at an increased risk of having a vitamin D deficiency^1,5

• Non-white ethnicity
• Diagnosis of Crohn’s disease
• If you have active disease
• If you’ve had an IBD-related surgery
• If you’ve taken to steroids (prednisone)
• If you are female
• If you are pregnant

Benefits of normalizing vitamin D levels (supplementing vitamin D)

Studies suggest that bringing your vitamin D levels back to their recommended levels through supplementation may⁴:

• Reduce the risk for IBD-related surgery
• Improved quality of life
• Decrease health care utilization
• Improve anxiety and depression scores

Vitamin D may also help certain biologics work better

While more research is needed to draw any definitive conclusions, some research suggests that vitamin D may be associated with improved outcomes with certain biologics such as infliximab (Remicade). Recent studies suggest⁴:

• Vitamin D supplementation improved the efficacy of infliximab (Remicade) in Crohn’s disease patients (especially for those deficient in vitamin D).
• Crohn’s patients receiving high doses of vitamin D were less likely to need dose escalation of Infliximab.
• Vitamin D supplement while on biologics may decrease skin issues associated with biologic use.
• Vitamin D levels may be positively correlated with trough levels (level of medication in your body) in those on Infliximab.
• Adults and children with low vitamin D levels may be less likely to achieve clinical remission regardless of the biologic they’re on.

How to correct a vitamin D deficiency

Work with your Crohn's or colitis dietitian nutritionist to make sure you're meeting the recommended intake of vitamin D and prior to starting any supplement.