ill tell you, im like a proud old man in the fact that i dont get sick often at all. Havent gotten a cold in 3 years
. I do two simple things.
1) dont touch your face. I see alot of people randomly run their hands down their faces, rub their tired eyes, lean their head on their hands. Now i cautiously dont touch my face for acne reasons, but i realized that the face is a huge portal for sickness causing pathogens to enter.
2) the biggest one, WASH YOUR HANDS! Im not ocd, but throughout the day i feel like a film builds up on my hands, so i wash them often. Major times i wash my hands is AS SOON as i get home from anywhere. I put my bag down and wash my hands with soap and water. We touch doors, car doors, papers, and so many surfaces that thousands of people, and insects which are huge carriers of viruses, have also touched. So dont go home and just go about your business, undress, eat, get on your computer, etc. Go wash your hands.
i dont have any special diet and dont take any vitamins. But even if like this past winter where every one in my house got sick simultaneously, i never got sick.