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Can Vitamin D help treat Crohn's and Ulcerative Colitis?

Updated: Jan 2

Crohn's and Ulcerative Colitis are chronic inflammatory bowel diseases that can cause prolonged diarrhea, soft, watery, or frequent bowel movements, spasmodic abdominal pain, fever, and sometimes bleeding in the gastrointestinal tract. These diseases are characterized by periods of flare-up and then remission.

During the flare-up phase, many patients often feel severe fatigue because of the disease itself or the medication they are taking. There might be a loss of appetite and decreased food intake, which results in eating a limited variety of foods, while, the nutritional need for nutrients, vitamins, and minerals is increasing.

Vitamin D deficiency in Crohn's and Colitis patients

Vitamin D is a common nutritional deficiency in most of the population and is insufficient in about 60-70% of patients with Inflammatory Bowel Diseases. Most of the vitamin in the body is created through sun exposure. However, there are foods that contain the vitamin in certain amounts:

Sources from the plant ( D2 form): Dried shiitake mushrooms.

Animal sources ( D3 form ): fish liver oil, fish (salmon, herring, tuna, mackerel, sardines), dairy products and eggs.

It is important for Crohn’s and Colitis patients to monitor vitamin D levels annually because they tend to suffer from its deficiency due to malnutrition and not enough sun exposure.

The role of Vitamin D in our body

Vitamin D participates in numerous processes in our body. It is one of the most important compounds for building and preserving bones. Patients with inflammatory bowel disease who take steroids for long periods of time are at risk of a decrease in bone density.

Vitamin D affects the composition of bacteria in the digestive system and helps reduce intestinal permeability. It also plays a significant role in regulating the activity of the immune system and that can affect the process of Inflammatory disease.

Vitamin D strengthens the gut barrier and protects it from immune disbalances and infectious conditions. It also encourages the prosperity of friendly bacteria in the gut, which in turn has positive outcomes for Crohn's and Ulcerative colitis diseases.

The normal levels of vitamin D in the blood should be higher than 30 ng/ml, if it is less than that, it is recommended to take it as a supplement, after discussing the dosage with your practitioner. The improvement in blood test values ​​is not immediate, and the results should be monitored over a period of several months.

Studies- The effect of vitamin D supplementation on Crohn's and Ulcerative colitis

Many studies have been done to assess the effect of vitamin D on chronic digestive disorders and to find out whether it can help treat Crohn's and Ulcerative Colitis.

A clinical study from 2015 examined whether it might affect fatigue and quality of life in Crohn's patients. The study was attended by 27 Crohn's patients whose disease was in remission. Half of them received vitamin D supplements at a dose of 2,000 international units per day and the rest received a placebo.

Before the start of the study and at the end of three months, the researchers measured the levels of vitamin D in the patient's blood using blood tests. They also measured their fatigue and quality of life using questionnaires and the strength of their hands - a measure that reflects muscle strength.

It was found that at the end of the three months the vitamin levels increased in the group that received the supplement and decreased in the group that received the placebo, compared to the levels measured before the start of the study.

In participants who received vitamin D supplements, the grip strength of both hands improved significantly, compared to those who received a placebo.

It was also found that patients who received the supplement and had vitamin D levels higher than 30 ng/ml had significantly higher quality of life and lower levels of physical, mental, and general fatigue, compared to patients who had lower levels of the vitamin in the blood and to patients taking placebo.

Another study open-controlled pilot study from 2016 was designed to examine the effect of taking a vitamin D supplement on gut bacteria and immune activity. Taking Vitamin D supplements has been found to lead to an increase in the variety of bacteria and a decrease in harmful bacteria in the upper gastrointestinal tract (stomach, duodenum), In the lower parts of the gastrointestinal tract, vitamin D was found to maintain less inflammatory environment and thus contribute to improving the bacterial composition in the gut. These fascinating findings may explain the beneficial effect of vitamin D in digestive disorders such as inflammatory bowel diseases and other bacterial infections.

So, if you are dealing with Crohn’s, Ulcerative colitis or any other chronic health condition it is always important to make sure your vitamin D levels are intact.

Note that the use of any food supplement should be under professional supervision, as with any medication.

Go get some sun!

The best way to top up your vitamin D levels is by sun exposure. Take advantage of sunny days and try to expose as much of your body as possible to the sun for about 20 minutes (this is usually when you start feeling the tingling feeling on your skin which means that it is absorbing the vitamin). Don’t use sunscreen or sunglasses (our eyes also absorb vitamin D), but make sure you are not exposed for too long. Getting burned is not part of the plan!

These are my favorite vitamin D supplements from Iherb:

Vitamin D and gut health
Vitamin D



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