The phrase "to poison the food" means to add harmful substances or chemicals to the food, making it dangerous or deadly for people to eat. Full definition
A middle aged man died and four of his friends were critically ill after eating poisoned food on Christmas day at Assin Breku in the Central region. (ghanapoliticsonline.com)
Tell me my cat did not get poisoned by the food and that my dead dog didn't die of poisoned food as well. (itchmo.com)
«But security experts also worry about a gene drive that could be used to gradually poison a food supply, or enable a mosquito to transmit more rather than less virus.» (sciencedaily.com)