The good news is there are some things you can do to prevent the flu. Of utmost importance is washing your hands often. At a minimum you should wash them before each meal and after every visit to the bathroom. It also helps if you can keep your hands away from your eyes, nose, and mouth. If you have to sneeze or cough, use a tissue or the crook of your arm. Better yet, if you're sick try to stay home so that you don't infect other people.
I mentioned Vitamin D earlier. Make sure your levels are good (by getting a simple blood test). If not your doctor will likely have you supplement with a D3 pill. Good nutrition goes beyond Vitamin D, though, and includes consuming plenty of fresh fruits and vegetables, whole grains, and lean fats. Try to avoid sugar, caffeine, and alcohol as much as possible.
One of my favorite ways to fight the flu is to get plenty of rest. Who doesn't want some of that? Try to bag at least 8 hours of sleep a night to give your immune system a fighting chance. Light, daily exercise has also been proven to boost immunity so try to get in a workout or walk whenever you can.
Of course, you also have the option of getting a flu shot. There is a lot of debate over whether or not these work. Scientists have to predict what strains of flu will come each fall and winter and then make the flu vaccine accordingly. Sometimes they get it wrong. Talk to your doctor and see if getting a flu shot is a good idea for you.
By taking these simple measures you will hopefully stay healthy this autumn and winter season!