Eating before the nucleic acid is usually not going to affect the results of the nucleic acid test.
Currently, nucleic acid testing can be used for the detection of the new coronavirus, HIV, hepatitis B virus, and hepatitis C virus. The purpose of the nucleic acid test is to detect the presence of virus-specific RNA (ribonucleic acid), which is not affected by dietary factors, so eating has no adverse effect on the results of the nucleic acid test.
Since most of the nucleic acid tests use nasopharyngeal swabs, it is easy to cause nausea or vomiting due to the irritation of the larynx, so it is recommended that the patient undergoes the nucleic acid test 2 hours after eating, so as not to trigger vomiting, which results in the vomiting of the stomach contents.
Personal precautions need to be taken during the nucleic acid test as the number of people is often large.