When scientists tested 446 plant compounds to see if they boosted your “innate” immunity, only two stood out: resveratrol found in grapes and pterostilbene found in blueberries. Boosting the immune system’s ability to fight bacterial infections is becoming more important as resistance to antibiotics grows, say the authors. They note that they did a cell culture study and that their findings do not prove that eating grapes or blueberries would strengthen immune functions, but it couldn’t hurt could it?