Crohn's disease, a nutritional guide

Crohn's disease is a relapsing systemic inflammatory disease, primarily affecting the gastrointestinal tract with associated extraintestinal manifestations and immune disorders. Along with ulcerative colitis, they are the two main components of inflammatory bowel disease.

It is a disease that primarily affects the gastrointestinal tract and frequently presents with abdominal pain, fever and clinical signs of intestinal obstruction or diarrhea with passage of blood or mucus or both.

What are the causes?

Genetics

Family aggregation has been known for over 70 years. To date, genomic association studies and computerized meta-analyzes have identified and confirmed 71 susceptibility loci for Crohn's disease on 17 chromosomes.

Environmental factors

In addition to genetics, several causes are possible, mainly related to lifestyle. The importance of the environment is suggested by the increase in incidence rates in previously less affected ethnic groups such as Asians and Hispanics and in immigrants from low-incidence regions moving to areas with traditionally high incidence.

Exposure to air pollution, a Western diet with excessive consumption of ready-to-eat foods (often containing high amounts of sugar and polyunsaturated fats) and increased use of tobacco are some of the factors most implicated.

Crohn's disease often occurs after infectious gastroenteritis and in people who have intestinal dysbiosis.

In addition, scientific research on animals suggests that viral infections - as an environmental factor - could convert genetic susceptibility to the evolution of the disease.

Microbiota and intestinal health

Crohn's disease appears to result from an altered interaction of the gut microbiota which is normally in a state of symbiotic reciprocity with the human host.

Smoke

Crohn's disease patients must stop smoking. Smoking promotes an aggravated course of the disease and a suboptimal response to medical therapy.

Nutrition

Following an alteration of the intestinal mucosa, nutritional deficiencies may often be present, and therefore it is necessary to be careful and be corrected. Let's analyze in detail the various food families.

Cereals

Research suggests that a high-fiber diet can reduce the risk of developing intestinal inflammation (IBD).

But once a diagnosis of IBD is received and the disease is active, fiber can be a problem. Insoluble fiber, found in the peels of fruit and vegetables, seeds, dark leafy vegetables, and whole grain products, can increase diarrhea and abdominal pain.

According to the Crohn's and Colitis Foundation of America (CCFA), people with Crohn's disease could benefit from a low-fiber, low-residue meal plan to help manage bowel constriction or acute symptoms.

Fruits and vegetables

Such foods can cause problems for the same reason as whole grains: high in insoluble fiber.

Not necessarily, however, it is necessary to eliminate all fruits and vegetables from the diet, but to limit some such as:

• apples with peels
• broccoli
• cabbage
• cauliflower
• artichokes
• cherries
• peaches
• plums

Protein and meat

Protein selection should be based on fat content, therefore meats with a higher fat content should be avoided such as:

• Red meat
• sausages

Dairy products

People with Crohn's disease should limit dairy products or avoid them altogether. This is because lactose intolerance tends to coincide with IBD.

Lactose, the sugar in milk, can increase the risk of gas or abdominal pain and diarrhea.

Drinks

Considering the nature of Crohn's disease, it is generally a good idea to drink more fluids. The best drink is undoubtedly natural water. Remember that dehydration is often a risk in chronic diarrhea. Avoid drinking, however:

• coffee
• tender
• wine, liquor and beer

Spices

Spicy foods can act as irritants for some and make symptoms worse. As a general rule, you should avoid anything that is too spicy. On the other hand, turmeric (or curcumin) has been linked to minimizing Crohn's disease flare-ups in preliminary studies.

Crohn's new research areas include:

• the use of probiotics
• the intake of omega-3 present in fish and flaxseed oil
• fish
• fibrous foods such as psyllium that are not digested up to the colon
• medium chain triglycerides found in coconut
• a low-FODMAP diet

It's important to consider that it's not just what you eat that can aggravate symptoms. How you cook and process your food can also make a difference. Fried and fatty foods are commonly reported to be culprits of flare-ups, so it's best to opt for baked and grilled foods instead.

Bibliography

• Prof Daniel C Baumgart et al. (2012). "Crohn's disease". Lancet, Volume 380, Issue 9853
• A Franke, DP McGovern, JC Barrett, et al. (2010). "Genome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease and susceptibility loci" Nat Genet
• A Dignass, G Van Assche, JO Lindsay, et al., The European Crohn's and Colitis Organization (ECCO). "The second European evidence-based Consensus on the diagnosis and management of Crohn's disease: current management" J Crohn's Colitis, 4 (2010)
• Cox et al. (2017). "Fermentable Carbohydrates [FODMAPs] Exacerbate Functional Gastrointestinal Symptoms in Patients With Inflammatory Bowel Disease: A Randomized, Double-blind, Placebo-controlled, Cross-over, Re-challenge Trial." ). J Crohns Colitis.
• Lirong Zeng et al. (2017). "Macronutrient Intake and Risk of Crohn's Disease: Systematic Review and Dose – Response Meta-Analysis of Epidemiological Studies" Nutrients