This article was written by one of our contributors; specialist dietitian – Kaitlin Colucci
Inflammatory bowel disease (IBD) is a chronic, long-term condition involving inflammation of the gut. The two main forms of IBS are Crohn’s Disease or Ulcerative Colitis (UC):
- Crohn’s disease can affect any part of the digestive tract from the mouth to anus (bottom)
- Ulcerative Colitis is limited to the colon and rectum only
The main symptoms of IBD include, but are not exclusive to:
- abdominal pain
- abdominal cramping
- rectal bleeding
- weight loss
Symptoms of IBD will come and go. People suffer with ‘flare-ups’ with heightened symptoms, and then periods of remission with no symptoms. Treatment will depend on the severity of symptoms with the aim to relieve symptoms and prevent them returning. This can include medicines, specific diet, or lifestyle changes, and in severe cases surgery.
Which nutrients are important in IBD?
Due to inflammation in the gut, IBD may stop the absorption of enough vitamins and minerals from food. Eating a healthy, balanced diet may help improve these levels. However, if blood tests show levels are low despite this, it may be recommended to take supplements to restore levels.
Having low levels of iron is common in people with IBD. Possible causes include a lack of iron in the diet, blood loss and problems absorbing iron from food. Lack of iron can lead to anaemia.
Common symptoms of anaemia include:
- feeling tired and lacking in energy
- feeling short of breath
- fast or irregular heartbeat
- pale skin
It can help to eat more iron-rich foods to increase the amount of iron in the diet. These include green leafy vegetables, cereals, and bread fortified with iron, eggs, meat and pulses like peas, beans, and lentils. It’s harder for the body to absorb and use iron from non-meat foods but having some vitamin C at the same meal can help. For example, having a glass of orange juice with a fortified breakfast cereal. Drinking lots of tea or coffee can make it harder for the body to absorb iron from food.
Vitamin B12 & folate
Most people can get enough Vitamin B12 from their diet, especially in foods such as meat, fish, milk, cheese, eggs, and some breakfast cereals with added vitamin B12. However, if following a vegetarian or vegan diet, eating only plant-based foods, then it is recommended to take a Vitamin B12 supplement. Folate works with vitamin B12 to produce red blood cells.
Both Vitamin B12 and folate are absorbed in the last part of the small intestine called the terminal ileum. For those who have inflammation in that area, or have had surgery to remove the terminal ileum, you may not be able to absorb vitamin B12. This can lead to low levels of vitamin B12 in the body, causing fatigue and tiredness. It may be recommended to have Vitamin B12 injections every three months to prevent levels of B12 dropping too low.
The only way the body can make vitamin D is when the skin is exposed to sunlight. There is some vitamin D in foods such as oily fish, egg yolks and foods with added vitamin D, like margarine and breakfast cereals, however this doesn’t tend to be enough alone to meet Vitamin D levels during the winter months (October-March). People with IBD are at risk of having low levels of vitamin D due to less absorption in the gut, which if left untreated, can put some people at risk of bone pain.
Calcium is important for strong bones and teeth. Calcium is found in foods such as dairy foods, fish with bones, like sardines, and foods with added calcium, like breakfast cereal and bread. Some people with IBD may develop lactose intolerance and therefore are unable to eat dairy foods so it may be recommended to start a calcium supplement.
For those on steroid treatment, it may also be necessary to take a calcium and vitamin D supplement as steroids can increase the risk of bone thinning over time.
For some people, during a flare-up they may need to follow a lower fibre diet to help remove certain foods that can irritate an inflamed bowel, worsen symptoms of IBD, or obstruct narrowed parts of the bowel.
Typically, foods to be removed on a lower fibre diet will include:
- nuts, seeds & pips
- fruit & vegetable skins
- skins of beans, pulses, lentils
- dried fruit
During remission, it is important to reintroduce some fibre back into the diet, as fibre is beneficial for gut health as well as overall health.
Lactose is a sugar found in dairy products, such as milk and yogurt. Lactose is broken down in the gut by an enzyme called lactase. People with Crohn’s disease can become at risk of lactose intolerance as the lactase enzyme is produced in the lining of the small intestine. If this part of the gut is inflamed, this may affect the production of lactase enzyme and you may not be able to produce enough to break down lactose in the gut. Symptoms of lactose intolerance wind, bloating, nausea, and diarrhoea. Following a low-lactose or lactose-free diet may help manage these symptoms.
If buying lactose-free dairy products or plant-based alternatives, ensure to always choose ones that are fortified with calcium. Even if you develop a lactose intolerance, you may be able to digest small amounts of lactose, such as a little milk in a cup of tea.
Lactose intolerance can often be transient, meaning that once the lining of the gut is healed, you can start producing lactase enzyme again and your tolerance to lactose can increase.
Special diets for IBD
No diet has been proven to help people with IBD, except for exclusive enteral nutrition in Crohn’s disease. This is a special liquid only diet that is sometimes used to induce remission during a flare up. It needs to be strictly adhered to for up to 4-8 weeks. The liquid diet provides all the nutrition needed, and therefore needs to be closely supervised by a dietitian. Exclusive Enteral Nutrition (EEN) is the most rigorously supported dietary intervention, but it is challenging to sustain long term. Sometimes ‘partial enteral nutrition’ is used in combination with whole foods.
However, some people find that specific diets may work for them. For example, there is evidence that the low FODMAP diet can help with symptoms such as abdominal pain, constipation and diarrhoea in people with inactive Crohn’s or Colitis. But it also cuts out some types of food that may be helpful in managing the conditions.
If you decide to follow any diet to help with your Crohn’s or Colitis, it’s important to discuss it with your IBD team first.
People with IBD are at risk to develop a number of nutrient deficiencies including iron, vitamin B12 and several other nutrients. This will depend on the type of IBD, the severity of the disease, and the person’s diet.
If you need further support, speak to your GP or IBD team.