Dave, a COVID long-hauler in the UK, told Insider that he developed "burning" acid reflux and "horrible nausea" after contracting COVID in 2020. Although he had a fairly strong stomach before he got sick, he found himself unable to eat his favorite foods and drinks — pizza, beer, coffee, and chocolate — without feeling awful afterwards. Dave, who also tweets and blogs about long COVID, requested that he be identified by his first name only due to privacy concerns.

Dave's experience isn't unique. In fact, he is one of the thousands of people who got COVID-19 in 2020 who have experienced persistent digestive problems like acid reflux, stomach cramps, constipation, and diarrhea long after their infections, according to a study published Tuesday in Nature Communications.

The new study found that those who were infected with the virus, even people who had mild cases, were significantly more likely to have stomach troubles compared to those who did not get COVID.

Researchers compared the medical records of more than 154,000 US veterans who got COVID with about 5.6 million peers who did not contract the virus. They found 9,605 people who had COVID later experienced issues affecting the digestive system, pancreas, or liver.

The risk of long-term gastrointestinal issues increased for those who were hospitalized with more severe COVID infections. On average, people who had COVID were 36% more likely to have long-term gastrointestinal issues compared to those who were not infected, according to the New York Times.

The most common stomach-related issue was gastroesophageal reflux disease (GERD), a type of acid reflux. Other commonly reported symptoms included abdominal pain, constipation, and diarrhea.