AIMS. To establish in young adults the hypolactasia prevalence, calcium daily dietary ingestion and lactose intolerance symptoms frequency. SUBJECTS AND METHODS. Transversal descriptive prevalence and analytic study. Hypolactasia frequency in 98 Colombian National University randomized medical students was determined by Respiratory Hydrogen Test. Daily calcium ingestion and lactose intolerance was requested. RESULTS. Hipolactasia was present in 56% of students. In hypolactasic subjects negatively calcium (-116 mg/d) and dairy (-123 mg/dia) consumption were associated to. Lactose intolerance was present in 14% without consumption difference. CONCLUSIONS. Hypolactasia prevalence was 56%. Dairy calcium ingestion was Inferior in these subjects, not associated to lactose intolerance. Hypolactasia and low calcium ingestion are osteoporosis risk factors in this group.