Malnutrition and Dehydration

How does IBD affect nutrition?

People with Crohn’s or colitis are at risk for a variety of complications related to nutrition. When there is any stress related to illness, the body has to work harder to maintain good nutrition. You may be at risk of becoming malnourished and dehydrated if you are not getting the nutrition you need.

When you have a poor appetite, vomiting, diarrhea, cramping, gas, bloating or abdominal pain, it is clear why you may not feel like eating. These symptoms can make you feel tired and drained of energy. You may avoid eating and drinking for fear of worsening your symptoms. This reduced nutritional intake can cause weight loss and growth impairment, specifically in children.  

When you are not eating well, and the nutrients you are eating are not being absorbed properly because of Crohn’s or colitis, you may experience nutritional deficiencies. People with IBD typically experience nutrient losses, such as B12, calcium, vitamin D, and iron, due to poor food intake, malabsorption that occurs during digestion, and loss of blood during bowel movements. When the body does not receive or absorb the necessary amounts of nutrients, it has more nutritional requirements to keep it in good health. 

Nutrition can affect changes in mood, energy, hydration, skin, hair and nail health. Other factors, like certain medications or surgery, and the gut microbiome can change the way the body absorbs specific nutrients.

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Iron deficiency is one of the most common deficiencies in people with Crohn’s or colitis resulting from malabsorption as well as blood loss. Iron helps carry oxygen throughout the body. A lack of iron can cause anemia, low energy, weakness, and fatigue. 

Iron is found in animal sources like lean beef, oysters, chicken, and turkey. It is also found in beans, lentils, tofu, cashews, dark green leafy vegetables, and whole-grains. In addition to diet and oral supplements, intravenous supplements are being used more frequently if anemia is severe.  

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Zinc plays a role in intestinal function, particularly in rapidly improving diarrhea. Zinc deficiency is known to contribute to diarrhea and decrease the body’s ability to reduce inflammation. 

Zinc is needed for the body's defensive (immune) system to properly work. It plays a role in cell division, cell growth, wound healing, and the breakdown of carbohydrates. It is also needed for the senses of smell and taste. People with diarrhea lose zinc in their stools, so diarrhea increases the risk of having low zinc levels.

High amounts of zinc are found in meats, fish, and shellfish – especially the liver and kidney of beef and poultry, and in oysters. Other common sources of zinc – in lesser amounts – include eggs, dairy products, beans, lentils, nuts, and whole grain cereals. 

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Vitamin D

Vitamin D helps the body absorb calcium, making it important for bone health. Without calcium and vitamin D, the risk of osteoporosis – weaker bones – is possible. Vitamin D also plays an important role in strengthening the immune system, decreasing inflammation, and a protective role by possible reducing the risk of colon cancer. 

Vitamin D is produced naturally when the skin is exposed to sunlight. It can be found in food sources such as fish, eggs, and dairy products. Common sources of vitamin D include salmon, sardines, tuna, shitake mushrooms, egg yolk, milk, yogurt, cheeses and breakfast cereals. In addition to diet, oral supplements are frequently prescribed for IBD. 

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Curcumin is a bright yellow chemical derived from the spice turmeric and is known to have anti-inflammatory properties which is why it can be a useful supplement for those with IBD. Small studies have shown that 2 and 3g supplementation of curcumin beneficially helped to increase the duration of remission in those with ulcerative colitis, however, more studies are required.

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Omega-3, a type of fat often found in fish oil, walnuts and ground flax seeds is known to have anti-inflammatory properties and therefore can help with reducing symptoms related to IBD. At this current moment in time, there is no available data showing a clear benefit of omega-3 supplementation beyond the recommended intake.

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