Lactose Intake Does Not Differ Among Participants With And Without Symptoms Of Lactose Intolerance

INTRODUCTION: Self-perceived lactose intolerance (LI) is associated with avoidance of dairy foods, and may put individuals at risk for nutritional deficiencies and associated adverse health outcomes. The extent to which an individual with self-perceived LI avoids dairy may be influenced by the severity of perceived symptoms. We aimed to examine daily lactose intake using a brief lactose assessment tool (LAT) in patients presenting for esophagogastroduodenoscopy with and without self-perceived LI and to evaluate the association between lactose intake and severity of LI symptoms. METHODS: We conducted a cross-sectional study of 34 adults ages 18–75 years with (n = 23) and without (n = 11) self-perceived LI who were referred for esophagogastroduodenoscopy. We excluded those with a history of eosinophilic esophagitis, inflammatory bowel disease, chronic pancreatitis or pancreatic insufficiency, celiac disease, peptic duodenitis, major abdominal surgery, recent antibiotic use, prior radiation therapy, or milk allergy. All participants completed an 8-item LI questionnaire assessing frequency and severity of LI symptoms and a brief LAT to estimate daily lactose intake. The LAT lists 42 dairy-containing foods. LAT responses were used to calculate daily lactose intake in grams/day using the U.S. Department of Agriculture database. Spearman correlation was used to assess associations between lactose intake and severity of LI symptoms after consuming dairy products (total symptom score, number of bowel movements per day, frequency of bowel urgency, and stool consistency). RESULTS: There were no significant correlations between daily lactose intake and total symptom score, number of bowel movements per day, frequency of bowel urgency, and stool consistency when consuming dairy for the overall group (Figure). Median (interquartile range) lactose intake for the overall group was 16.9 (10.2–24.5) g/day. There was no significant difference (P = 0.61) in daily lactose intake between individuals with (18.9 g/day [9.2–26.4]) and without self-perceived LI (15.7 g/day [11.8–18.1]). CONCLUSION: Daily lactose intake is low in patients presenting for esophagogastroduodenoscopy when compared to national norms of two servings of dairy foods per day; intake does not differ by self-perceived LI status or severity of LI symptoms. Results suggest that consumption of dairy products in patients with gastrointestinal conditions or symptoms are influenced by factors other than symptoms of LI.Figure 1.: Scatter plot of relationships of daily lactose intake and symptom severity when consuming dairy products (total symptom score [A], number of bowel movements [B], frequency of bowel urgency [C], stool consistency [D]).