A study among laboratory rodents has shown that fruits and vegetables can be a good way to fight the flu. Quartcetin, a chemical close to resveratrol, is high in these products, especially in red onions, broccoli, grapes, blueberries, red wine and tea. Its antiviral properties have been demonstrated in cell cultures and in some animal studies. If this also applies to humans, it could be used as a means of boosting the immune system under conditions of physical and mental stress.

In the study, two groups of mice were subjected to exercise through a treadmill, one with two quartzetine and the other not. Two other groups were left alone, one administered the substance and the other not. They are exposed to the H1N1 flu virus. Increased exercise increases susceptibility to viral infections. However, it can be negative when taking quartcetin.