Inflammatory Bowel Disease
What is it?
Inflammatory bowel disease (IBD) is the term given to a group of disorders that cause inflammation or ulceration in the small and large intestines. IBD is divided into two major categories: ulcerative colitis and Crohn's disease. Ulcerative colitis appears to be slightly more common than Crohn's disease. The rate of IBD is increasing in Western cultures whereas it is virtually unknown in countries where people eat less refined foods. IBD can occur at any age but it is most common in those aged from 15 to 35.
Symptoms of inflammatory bowel disease
Ulcerative colitis causes inflammation and ulceration of the inner lining of the large bowel. The most common early symptoms are constipation with passage of blood or mucus in the stools. It may be months or years before diarrhea and abdominal pains develop.
Crohn's disease may affect any part of the upper and lower intestine, but most commonly the last part of the small intestine and/or parts of the large bowel. In Crohn's disease, the inflammatory reaction spreads throughout the entire thickness of the bowel wall. The symptoms of Crohn's disease are abdominal pain, especially in the right lower area of the abdomen, and diarrhea. There may also be rectal bleeding, weight loss and fever. The onset of Crohn's disease is often slow and insidious.
The most common complication of Crohn's disease is blockage of the intestine due to thickening of the bowel wall. In more severe cases, communicating passages known as fistulas, may develop between the affected bowel and other parts of the bowel, bladder, vagina or skin. Other complications include arthritis, skin problems, inflammation in the eyes and mouth, kidney stones and gallstones. Inflammatory bowel disease is a chronic condition that can recur at various times during a person's life. Some people have periods of remission, which can last for years, when they are free of the symptoms; and there is often no way to predict when the symptoms will return. IBD can be particularly serious in children as it can severely affect growth and development. Crohn's disease is also likely to increase the risk of gastrointestinal cancer.
Causes of inflammatory bowel disease
There are various theories about the causes of IBD. Genetic factors, modern diets high in sugar and refined foods, and viral and bacterial triggers may contribute to the disease. Smoking may also play a role. As IBD is increasingly prevalent in countries where diets are high in refined foods and low in fruit, vegetables and fiber, diet is likely to play a part in the cause and progression of the disease.
In an effort to understand some of the dietary factors which may be involved in the development of IBD, researchers involved in a 1997 study examined the pre-illness diets of 87 patients with recent IBD (54 ulcerative colitis and 33 Crohn's disease) and compared these with 144 healthy people. The results showed that a high sucrose consumption was associated with an increased risk for IBD. Lactose consumption showed no effect while fructose intake decreased the risk of IBD. A high fat intake was associated with an increased risk for UC; this was particularly marked for animal fat and cholesterol. A high intake of fluids, magnesium, vitamin C, and fruits also decreased the risk. Most of the findings were similar in ulcerative colitis and Crohn's disease except for potassium and vegetable consumption, which only seemed to decrease the risk for Crohn's disease.1 Increased sensitivity to yeast, food intolerances and immune abnormalities may play a role; although it is often unclear whether these are a cause or a result of the disease. Psychological factors are said to play a part in the progression of the disease.
Treatment of inflammatory bowel disease
Therapy for Crohn's disease aims to correct nutritional deficiencies and control inflammation, abdominal pain, diarrhea and rectal bleeding. Drugs are often used to control symptoms such as abdominal cramps and diarrhea. These include sulfasalazine drugs, corticosteroids and immunosuppressive drugs, many of which have adverse side effects if taken for long periods. The wide variety of treatments gives an indication of the inadequacy of drug therapy for curing the disease. In severe cases, surgery may be used to remove diseased sections of bowel and 50 per cent of people need more than one operation. Parenteral nutrition may also be used in severe cases.
Inflammatory Bowel Disease and diet
Nutritional deficiencies are common in sufferers of IBD. In a 1998 study, Dutch researchers evaluated nutritional status in 32 patients with Crohn's disease. They measured body composition, dietary intake, biochemical indexes of nutrition, and muscle strength. The results showed that daily intakes of fiber and phosphorus were significantly lower in Crohn's disease patients than in healthy people. Serum concentrations of beta carotene, vitamin C, vitamin E, selenium, magnesium, vitamin D and zinc, and activity of the enzyme, glutathione peroxidase were also significantly lower in Crohn's disease patients. Percentage body fat and hamstring muscle strength were significantly lower in male Crohn's disease patients than in healthy people.2
The aim of dietary therapy in IBD is to improve nutritional support and diminish inflammatory processes. It centers around high fiber and low refined sugar diets. However, wheat is a common allergen and wheat fiber may not be suitable for use in IBD patients. It is important to be aware that raw fruit and vegetables may be irritating during an active phase of the disease.
It is very likely that food allergies and intolerances play a role in IBD, and identifying and eliminating offending foods is likely to be useful in any treatment program. This applies particularly to wheat and dairy products. Lactose intolerance may be particularly prevalent in IBD sufferers. Elemental diets are often used to treat Crohn's disease and consist of all the essential nutrients, with protein provided as pre-digested or free-form amino acids. However, most patients relapse when they return to a normal diet. Along with an increase in fiber, elemental and elimination diets seem to alter the gut environment favorably, resulting in a healthier balance of micro-organisms and a decrease of toxin production. This contributes to clinical improvement.
There has been considerable interest in recent years on the influence of fat on the occurrence of IBD and it is possible that elemental diets produce beneficial effects because of their fat composition.3 Increases in recent years in the frequency of Crohn's disease in Japan have been correlated with increased dietary fat intake and fatty acid deficiencies; omega-3 fatty acid deficiencies in particular, have been seen in Crohn's patients.4
IBD sufferers should also avoid food additives such as carrageenan and sorbitol. Carrageenan, a compound extracted from seaweed, is used as a stabilizing and suspending agent and is often found in milk and chocolate milk products. The alterations in gut bacteria which are often seen in Crohn's disease patients may make them particularly susceptible to carrageenan-induced damage. Caffeine and stimulant drugs should also be avoided. Some patients have benefited from macrobiotic diets and fasting.
Vitamins, minerals and inflammatory bowel disease
Antioxidants
Inflammatory damage in IBD may be mediated by free radicals and sufferers may be deficient in antioxidant vitamins. Increasing intake of antioxidants may protect against this damage. In a 1996 study published in the American Journal of Clinical Nutrition, researchers at the University of Colorado investigated antioxidant concentrations in the blood plasma of children with IBD. The study involved 12 children with Crohn's disease and 12 with ulcerative colitis. Their blood levels of vitamin C, glutathione, glutathione peroxidase and vitamin E were compared with those of 23 healthy children. The results showed that levels were lower in IBD sufferers, particularly those with Crohn's disease.5 Other studies have shown low levels of vitamin A in children suffering from the disorder.6
Vitamin A
Low serum vitamin A levels are found in many Crohn's disease patients. Vitamin A is important for maintaining a healthy gut lining.
B vitamins
Folic acid
Some of the drugs used to treat IBD, such as sulfasalazine, may deplete folic acid. Folic acid is essential for tissue regeneration and to protect against genetic damage which may possibly lead to cancer. As there may be an increased risk of developing cancer in those who have ulcerative colitis, folic acid supplements may be useful in preventing this. A woman taking sulfasalazine drugs who plans to get pregnant should take folic acid supplements to help prevent neural tube defects.
Vitamin B12
Vitamin B12 supplements may be useful in sufferers of Crohn's disease as this vitamin is absorbed in the area of the intestine most commonly affected by Crohn's disease.7
Vitamin D
Reduced fat absorption can lead to vitamin D deficiency. Patients with IBD may have lower serum levels of vitamin D than healthy controls, despite normal intake. This may increase the risk of osteoporosis. Anti-inflammatory corticosteroid drugs, which are often given to IBD sufferers, may also increase the risk of osteoporosis, and vitamin D and calcium supplements may help to decrease this risk.
Iron
The gastrointestinal bleeding seen in IBD commonly leads to iron deficiency and anemia. However, large doses of iron may increase oxidative damage and promote intestinal infection, and should be avoided by IBD sufferers.
Magnesium
Magnesium deficiency is often found in IBD sufferers. However, large doses of magnesium supplements may have a laxative effect and should be taken with care.
Zinc
Disturbances in zinc metabolism have been shown in patients with inflammatory bowel disease. Several studies have found decreases in absorption and serum zinc levels, and increased excretion. The copper-to-zinc ratio appears to be higher in those with active disease. Zinc deficiency may be due to low intake, poor absorption and excess losses in the feces.8 The concentration of superoxide dismutase, a copper and zinc-containing protein involved in the scavenging of free radicals, may be decreased in the gut lining of patients with IBD, which could contribute to inflammation.
Supplements and inflammatory bowel disease
IBD impairs digestion and absorption, and because of this a high percentage of sufferers are malnourished. This malnutrition may in turn worsen bowel function, leading to further problems. Many sufferers are deficient in protein and calories and have a fat intolerance which results in fat-soluble vitamin deficiencies. Diarrhea promotes depletion of water-soluble B vitamins and essential minerals like zinc and magnesium. Vitamin and mineral supplements are extremely useful in the treatment of IBD; with zinc, magnesium, folic acid and antioxidants being particularly beneficial. Nutritional supplements are also important when patients need extra nutrients; for example, in children with growth retardation.
However, problems can arise from large doses of supplements as high doses of vitamin C, magnesium, zinc and iron can irritate the digestive tract and worsen diarrhea. Slow gradual repletion of nutrients by mouth may be the most effective way to supplement in IBD.
Nutrients and inflammatory bowel disease
Essential fatty acids
Essential fatty acid supplements have been shown to have beneficial effects in the treatment of IBD as they may correct abnormalities in fatty acid and prostaglandin metabolism, and act to reduce inflammation. A 1996 Italian study published in the New England Journal of Medicine showed beneficial effects of fish oil in treating Crohn's disease. Researchers involved in the one-year, double-blind, placebo-controlled study investigated the effects of an enteric fish oil preparation on the maintenance of remission in 78 patients with Crohn's disease who had a high risk of relapse. Every day, the patients received either nine fish oil capsules containing a total of 2.7 g of omega-3 fatty acids or placebo. The proportion of patients in the treatment group who remained in remission after a year was 59 per cent, compared to only 26 per cent of patients in the placebo group. Enteric-coated capsules may be particularly useful as side effects such as unpleasant taste, bad breath and diarrhea are minimized.9
Probiotics
The composition of gut bacteria is often unfavorable in Crohn's disease and probiotic supplements may be useful in correcting these abnormalities and improving gut function.10 Researchers involved in a 1996 study found improvements in the function of the immunological barrier of the gut in patients given Lactobacillus supplements.11
Herbal medicine and inflammatory bowel disease
Herbal treatment of IBD involves the use of plants which soothe irritated mucous membranes such as slippery elm bark (Ulmus fulva), marshmallow (Althaea officinalis) and aloe vera (Aloe vera). Other herbs that may be useful include echinacea, (Echinacea angustifolia or E purpurea) and goldenseal (Hydrastis canadensis).