Certain Foods Prevent Illnesses

Posted February 16th, 2010 by Elaine Hastings, RD - Nutrition Expert and filed in Meal Tips

In the same way that children wish for super hero powers, most of us would like to possess the ability to fight off the threat or onset of germs, the common cold or flu. In an average season, about 20 percent of Americans get the flu. This year, the H1N1 virus has led to many new flu cases, and finding ways to protect our immune systems from unhealthy invaders is mission critical.

Without super powers, we must rely on the forces we can control. Fortunately, foods with powerful nutrients and antioxidants can improve our immune system and help our bodies fend off viruses, toxins and even cancer cells. By including these nutrients in our daily eating habits, we can help strengthen a body’s immune system and improve our chances of staying healthy.

By increasing the number of white blood cells in the body, nutrients help rid our system of unhealthy toxins.

Important nutrients include beta carotene; vitamins C, D and E; iron, zinc; flaxseed oil; omega-3 fatty acids; garlic, selenium; and bioflavonoid which include citrus fruits, rose hips and other plants.

Topping the list are the three major antioxidant vitamins: beta carotene, vitamin C and vitamin E. You’ll find them in colorful fruits and vegetables such as those with purple, blue, red, orange and yellow hues. To get the biggest benefits of antioxidants, eat these foods raw or lightly steamed; don’t overcook or boil.

Found in yellow and dark green vegetables, beta carotene increases the percentage of white blood cells in the body, acting as another defender of immunity. The best way to get beta carotene is in fruits and vegetables such as kale, spinach and carrots. 

Vitamin C enhances the function of immune cells and can be found naturally in citrus fruits, melons, berries, peppers, sweet potatoes and peas.

Vitamin E aids in the production of antibodies that destroy bacteria. In a Harvard School of Public Health study, researchers found that vitamin E lowers the risk of cardiovascular disease. Good sources for this vitamin are avocados, whole grains and greens.

In addition to the top super three above, Vitamin D is also essential to a healthy diet. Yogurt and other cultured milk products that contain probiotics, beneficial bacteria with immune-boosting benefits, are especially important. Look for the “live active culture” seal, which indicates that probiotics have been added. Early research shows that vitamin D may be linked to a seasonal increase in colds and flu and a higher incidence of respiratory infections.

In addition, iron is required for the body to manufacture white blood cells. Iron can be found in healthful foods such as apricots, lentils, kale and beets. Another important nutrient the body needs is zinc, to help heal wounds and strengthen its resistance to cold viruses. Zinc also is found in whole grains, seeds and beans.

The antioxidant selenium also is found in whole grains and seeds, as well as mushrooms.

Another immune-boosting hero, omega-3, is filled with fats that increase the activity of white blood cells that eat up bacteria and help strengthen cell membranes. These also speed up healing and strengthen resistance to infection in the body. In addition, flax oil and flaxseeds, salmon, mackerel, tuna, omega-3 eggs, nuts and seeds are all excellent sources of omega-3. An easy way to include omega-3 in your diet is to add ground flaxseed to baked goods, yogurt, cereal or smoothies

Garlic, with antibacterial, antiviral and antifungal agents, can also increase immune function. Garlic is an antioxidant that reduces the build-up of free radicals in the bloodstream. In addition, garlic is a good source of sulfur, which is important for healthy liver function.

Bioflavonoid aids the immune system by protecting the cells of the body against pollutants trying to attach to them. A diet that includes several servings of fruits and vegetables daily will ensure that you get the bioflavonoid needed to help your immune system work the best.

In every superhero story, there are always the villains. When it comes to your body’s immune system, there are certain foods that pose a threat to the body’s defenses. For example, consuming too much sugar, equal to drinking two cans of soda, can reduce the body’s ability to kill germs. Alcohol intake can harm the body’s immune system, suppressing its ability to produce more white blood cells. The more alcohol is consumed, the more it suppresses the immune system.

In addition, foods high in saturated fat and oils can increase the risk of obesity and harm your body’s ability to fight disease. White blood cells have to fight harder to multiply or produce antibodies, leaving your body more susceptible to germs or other “invaders.”

If you aren’t getting enough antioxidants and other essential nutrients in your diet by eating produce, a physician or registered dietitian may recommend a multivitamin. However, some nutrients can only be found naturally in foods. Be cautious when considering immune system supplements to boost immunity. Consult your physician or a dietitian who can recommend the proper vitamin regimen. Getting too much can be toxic.

By adding these super foods to your diet, you can help your body prevent — or better fight off — colds or flu this season.

In addition, you can develop healthier eating habits and contribute to overall improved nutrition and health.