In 1942, Andresen studied 50 patients with ulcerative colitis. Food allergy was found to be the cause in 67 percent of the patients, all of whom showed a satisfactory response to dietary modification.23 Rowe and Rowe reported that 49.4 percent of 170 patients with ulcerative colitis could be successfully managed with anti-allergy therapy alone, without the need for corticosteroids or other medications.24
Rider and Moeller injected extracts of wheat, egg and milk into the rectal mucosa of 20 patients with ulcerative colitis.25 Some 80 percent of the patients showed a positive reaction (edema, erythema, capillary engorgement) to at least one of the food extracts. Fifteen patients who had a positive intramucosal test were prescribed diets free from the offending food or foods. Fourteen of these patients (93%) experienced complete remission or significant improvement.
Rudman et al maintained four patients with regional enteritis (Crohn's disease) on a gluten-free, lactose-free diet for 12 days, after which they were challenged with 5-20 g/day of gluten for up to 12 days. Various reactions, including melena, fever, abdominal pain, diarrhea, steatorrhea, and nausea developed in all cases, within 4-9 days of beginning the gluten challenge. In all cases, these reactions subsided within 2-4 weeks after discontinuation of gluten.26
In another study, 50 patients with ulcerative colitis were randomly assigned to a milk-free diet or a control diet for one year.27 During the follow-up period, 38 percent of the patients on the milk-free diet remained free of relapses, compared with 21 percent of those on the control diet. Three or more relapses occurred in 12 percent of patients on the milk-free diet, and in 33 percent of those on the control diet (statistical analysis not presented).
Jones et al induced remission in 20 consecutive patients with active Crohn's disease by administering an elemental diet or total parenteral nutrition.28 After the patients had achieved remission, they were randomly assigned to receive a control diet (high in fiber and unrefined carbohydrates) or to perform individual food challenges and to exclude from the diet those foods which provoked symptoms. Seven of the 10 patients on the exclusion diet remained in remission for 6 months, compared with none of 10 patients on the control diet (p < .05). In an open trial, 51 of 77 patients on the exclusion diet alone remained well for periods of up to 51 months. After 2 years, 65 percent of those patients were still in remission. The most frequent symptom-provoking foods were wheat, dairy products, Brassicas (cabbage, broccoli, cauliflower, etc.), corn, yeast, tomatoes, citrus fruits, and eggs.
In another study, 21 patients with an acute exacerbation of Crohn's disease were randomly assigned to receive either 1) prednisolone or 2) an elemental diet followed by gradual reintroduction of foods after four weeks.29 Assessment of disease activity after 4 and 12 weeks showed that the group receiving the elemental diet improved as much as, and by some criteria more than, the steroid-treated group. These results suggest that elimination of food antigens from the diet can induce remission in patients with active Crohn's disease.
In a 1993 study, 136 patients with active Crohn's disease were given an elemental diet.30 Of the 93 patients who continued the diet for 14 days, 78 (84%) achieved clinical remission and were then randomly assigned to receive corticosteroids or dietary treatment. The diet group was instructed to introduce one new food daily, and to exclude any food that precipitated symptoms. The median length of remission was 7.5 months in the diet group, compared with 3.8 months in the corticosteroid group. Of the patients who followed the diet, 45 percent remained disease-free for at least two years.