I have good news and bad news. The bad news: Every year, the average North American gets three colds, and has a 20% chance of getting the flu. The good news: If you eat the right foods, you may not get those three colds or the flu! So here's what you should - and shouldn't - eat and drink if you want to stay healthy this winter.

We'll start with the foods you should eat:

  • Fish. Wild salmon, mackerel, herring, and other fatty fish contain omega-3 fatty acids - which increase activity of the cells that fight flu by eating up bacteria. That's according to a study by Britain's Institute of Human Nutrition and School of Medicine. Other research shows that omega-3s increase airflow and protect lungs from colds and respiratory infections.
  • Carrots and sweet potatoes. These foods contain Vitamin A - which plays a key role in preventing and fighting off infections. Try to eat your carrots and sweet potatoes with zinc-rich foods. For example, you could have pot roast - which contains zinc - with your carrots. Why? Because without zinc, your body won't be able to use the Vitamin A.
  • Here's what you should DRINK if you want to stay healthy: Black tea. Immunologists at Harvard report that people who drank five cups of tea every day had 10 times more cold and flu-fighting proteins in their body! Don't like black tea? Green tea works, too.

Now, here's what you shouldn't eat or drink if you want to stay healthy this winter:

  • Soda. A study published in the American Journal of Clinical Nutrition found that eating 100 grams of sugar - which is the amount of sugar in three cans of soda - significantly impacted the ability of white blood cells to kill bacteria for up to five hours afterward.
  • Stay away from foods loaded with calories, like those double cheeseburgers. Why? Because they can cause you to gain weight, and excess weight can cause inflammation that impairs the immune system's ability to fight infection.