Comparative Study of Lactose Intolerance in Rural and Urban Population in Bangladesh

Lactose intolerance is a common problem worldwide, especially in tropical areas. This study was carried out to see the comparison of prevalence of lactose intolerance and its symptom pattern in rural and urban areas. Fasting blood sugar and blood sugar after 30 minutes of intake of 25 gram lactose was measured in apparently healthy volunteers. Blood sugar level rise <1.1 mmol/l after 30 minutes was considered as positive lactose tolerance test. Specific symptoms like abdominal pain, diarrhea, vomiting, flatulence, nausea, headache, muscle pain and frequency of micturition were noted from the participants over 24 hour period. Among 133 participants, 57 were male and 76 were female with mean age of 31.17±10.63. Prevalence of lactose intolerance in urban,rural and total study population were 80.6%, 83.3%and 82.0% respectively. Male were slightly more lactose intolerant than female. Most significant symptom in overall population was borborygmi (P=0.048). In urban population the most significant symptoms were flatulence (P=0.009) and nausea (P=0.017), while in rural population it was borborygmi (P=0.013). Borborygmi (P=0.005), flatulence (P=0.001), diarrhea (P=0.032), nausea (P=0.025) and vomiting (P=0.025) shows good significance in regression analysis of overall study population. There is no significant difference in prevalence of lactose intolerance between urban and rural area. But there are differences in symptoms which develop after lactose intake in these two distinct groups.