Can you take a dna test wrong, because i was eating before i took the test and someone told me that it can affect the results of testing is that true?

Not in my opinion: When they take a swab of your check they are picking up cells to culture for the dna test. They are now also using blood draw for the dna test to get a complete dna makeup to let you know what you may be at risk for or if your dna precludes use of certain drug therapies. Either way i would not worry as I am sure they can tell your dna from your meals.