Would eating or drinking before collecting my DNA affect my results?

Drinking or eating will not change the results in any way. A positive will not become a negative and a negative will not become positive. The reason that you are not supposed to drink or have anything in the mouth for an extended period prior to collection is to ensure that we have enough buccal cells to complete the test. If there are not enough cells to complete the test, then the results will not be released and a recollection will be required.