A proper diet can help prevent malnutrition and avoid nutrient deficiencies. Eating well will improve energy levels, help with symptom management, enhance immunity and the body’s ability to heal, and improve overall quality of life. It is important to focus on meeting energy and nutrient needs as individuals with ulcerative colitis may be at risk of becoming malnourished.
Malnutrition occurs when the body is lacking nutrients – from suboptimal intake through diet, from malabsorption or loss of nutrients in the gastrointestinal tract. When malnutrition occurs common side effects are rapid or unintentional weight loss, and worsened fatigue. There are a few reasons individuals with ulcerative colitis may be at risk for malnutrition. For one, it is common to experience a loss of appetite with the disease whether it comes from a general sense of feeling unwell during a flare, or a fear that eating anything will worsen symptoms. This decrease in appetite often leads to a decrease in food intake. Another common issue with ulcerative colitis is that individuals may have a variety of food intolerances that greatly restrict usual intake. Other factors that may put patients with the disease at risk for malnutrition include increased nutrient and caloric requirements from the state of chronic disease itself, side effects of medications, blood loss from the intestine, and malabsorption of nutrients - especially when inflammation is present.
It is important to first understand the general process of digestion before realizing the effects of ulcerative colitis on nutrient digestion and absorption. Digestion can be defined as the process of food being converted into substances that can be absorbed by the body. The body absorbs nutrients from food to function properly. Most absorption of nutrients occurs in the duodenum or jejunum, the first two portions of the small intestine, with the exception of vitamin B12 which is absorbed in the ileum. Watery food residue and undigested secretions pass into the large intestine, or colon, where water is recycled. Solid, undigested food mixes with bacteria living in the large intestine to form bowel movements. In ulcerative colitis, the small intestine is not affected. However, the inflamed colon may cause urgency and does not recycle water properly, leading to diarrhea. Nutrient deficiencies mostly occur from intestinal blood loss with inflammation and from increased losses with frequent bowel movements and diarrhea.
There are many nutrients at risk of deficiency with ulcerative colitis especially when there’s a decrease in food intake. However, certain nutrients are at a higher risk of deficiency. The degree of which certain nutrients are at risk often depends on the severity of inflammation. The macronutrient at largest risk is protein. Bowel protein loss is correlated to the extent of intestinal inflammation – when more inflammation is present there are more protein losses from the bowel, and extra attention should be placed getting enough protein in the diet. Folate may be at risk when being treated with methotrexate and sulphasalazine as they specifically increase folate requirements. If folic acid supplements are taken for a prolonged period of time, it is important to monitor vitamin B12 levels as folic acid can mask a vitamin B12 deficiency. Calcium and vitamin D are at risk when using steroids over a prolonged period of time, and possibly from decreased intake if lactose intolerance is an issue. Minerals at risk include iron, zinc and magnesium – primarily due to intestinal blood loss and chronic diarrhea.
Suggested Article: Practical Strategies for Optimal Nutrition
Below is a chart summarizing nutrients at a higher risk of deficiency with ulcerative colitis, and dietary sources of these nutrients:
For more information on how to avoid malnutrition and meet energy and nutrient needs, we also have an article on “Practical Strategies for Optimal Nutrition".