Exocrine pancreatic insufficiency (EPI) is frequently described as underscreened, underdiagnosed, and undertreated. The treatment for EPI is pancreatic enzyme replacement therapy (PERT), which is costly, and provider confidence in prescribing may be one barrier to reducing undertreatment. The lack of interchangeability studies for prescription PERT and/or lack of efficacy studies of over-the-counter enzyme options may be another barrier. This paper reviewed the prevalence of EPI in the general population and in co-conditions. Prevalence of EPI in the general population is commonly estimated around 10-20%, and further research is needed to evaluate EPI across all age groups and to better understand in which age group EPI becomes more prevalent, as an age effect is often seen in EPI prevalence studies. EPI is perceived to be highly correlated with certain co-conditions, and the majority (~65%) of EPI literature is related to a co-condition such as cystic fibrosis, pancreatitis, post-surgery, cancer, or diabetes. It can be estimated that 85% of literature in identified co-conditions, or 56% of total EPI literature, is on rarer co-conditions which only represent <1% of EPI overall. In contrast, there is very little research and literature on EPI in the general population. The highest absolute rates of EPI with co-conditions are likely diabetes and possibly irritable bowel syndrome with diarrhea, yet they are among the least commonly researched in co-condition and EPI studies. A lack of research on EPI in the general population and in the more common co-conditions may be contributing to the rates of underdiagnosis and underscreening, as well as undertreatment for those with low fecal elastase-1 levels.