How to Keep Your Immune System Strong

Enhancing immunity is a thriving topic in the nutraceutcial markets today. Nutritionists agree that a poor diet is the number one reason we become susceptible to cold weather illnesses.

There is no cure for the common cold or flu, but eating well during this season may help you avoid getting sick. Science is busy discovering links between our immune system and protective components in food.

More: Winter and Nutrition

Here are some top nutritional keys to stay healthy this season:

Vitamin C

Vitamin C tops the list of immune boosters. There has been more research about the immune boosting effects of Vitamin C than perhaps any other nutrient. Vitamin C is available naturally in many fruits and vegetables.

Unlike most animals that produce their own Vitamin C, the human body does not synthesize any. Vitamin C has substantial antiviral and antibacterial benefits though it's known for its protective aspects in creating host resistance. The most abundant vitamin C foods are guava, papaya, strawberries, kiwi, cantaloupe, orange and grapefruit.

More: 4 Ways to Flu-Proof Your Winter


The live cultures found in yogurt, particularly Lactobaccilus and Bifidobacteria, may be beneficial in enhancing immunity. Having a healthy supply of gut flora increases a person's white blood cell production and activity. They may also boost the immunity while taking antibiotics, and they supply added protection to those who may have a compromised immune system.

In a recent Swedish study, those who drank a daily supplement of Lactobacillus reuteri (a specific probiotic that appears to stimulate white blood cells) took 33 percent fewer sick days than those given a placebo. Probiotic rich foods are yogurt, kefir, select cheeses and milk, sauerkraut, kim chi and tempeh.


Mushrooms are antioxidant-rich and very high in selenium. Selenium has been studied to reduce the risk of developing a severe flu. Mushrooms are also recognized for there antiviral, antibacterial, and anti-tumor effects. White button mushrooms in particular have noticeably greater immune boosting effects than other mushrooms such as, oyster and shiitake.

High Fiber Grains

Oats and barley in particular contain beta-glucan, a type of fiber with antimicrobial and antioxidant capabilities. They enhance resistance to various fungal, bacterial and viral diseases. Beta-glucan is also found in protective amounts in shiitake and maitake mushrooms. Beta-glucan enhances immunity, similarly to echinacea and astragalus root. Beta-glucan binds to macrophages and other white blood cells and activates anti-infection activity by increasing the production of free radicals.

Vitamin E

Vitamin E has been studied for its production of natural killer and B-cells, the cells that produce antibodies that destroy bacteria. The highest vitamin E foods are green leafy vegetables, sunflower seeds, almonds and blueberries.

More: Eat Your Illness Away