Document Type


Date of Degree Completion

Spring 2021

Degree Name

Master of Science (MS)



Committee Chair

Susan Hawk

Second Committee Member

David Gee

Third Committee Member

Tafere Belay


Lactose intolerance disproportionately affects racial minority groups in the United States, increasing the incidence of calcium deficiency and low bone mineral density in these populations. The nutritional quality of lactose-containing food products incentivizes the investigation of long-term treatment options for lactose intolerance. Modifying the gut microbiome to increase the quantity of lactose-hydrolyzing bacteria in the intestines is a promising avenue of treatment that merits investigation. Such modification is typically achieved via consumption of probiotics, prebiotics, or synbiotics in various forms. This systematic review examined 25 studies measuring outcomes of lactose intolerance in subjects given probiotic, prebiotic, or synbiotic treatments. Bacterial strains with the greatest degree of evidence for the reduction of undesirable outcomes of lactose intolerance were Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus delbrueckii subspecies bulgaricus, and/or Streptococcus thermophilus. Inoculated dairy products also showed strong evidence for the attenuation of lactose intolerance outcomes.