These foods can worsen your cold or flu within an hour. Here is how what you need to stay away from.

Processed Sugars:

Anything loaded with sugars like soda, juices and artificially flavored drinks can cause inflammation and weaken the body’s white blood cell count, which reduces resistance towards foreign organisms.

Dairy:

If you have a cold then dairy products can thicken existing phlegm so try and avoid it as much as possible. It may not have this effect on some, so try a bit and see how things work.

Alcohol: 

Like sugar, alcohol causes inflammation and reduce WBC efficiency. Avoid drinking and stick to broths and fresh juices.
Refined Carbs: They breakdown into sugar and increase blood sugar. This again makes it difficult for your body to fight off and infection.