A new study shows Americans owe about $140 billion in unpaid medical expenses. In the study, published in the Journal of the American Medical Association, researchers at Stanford estimated that just under 18 percent of adults had medical debt, averaging about $429. The average medical debt was highest in the South at $616. The $140 billion of medical debt is almost double the amount in 2016, and it’s greater than even personal debt in this country. This debt could have a huge impact on healthcare. People facing financial challenges due to medical expenses often avoid seeking medical care, even when needed.