Your immune system is responsible for fighting foreign invaders in the body, such as pathogenic bacteria and viruses. It also destroys body cells that become mutated or cancerous. Poor nutrition results in reduced immune function which leads to increased infections and slower healing. Immune function tends to decrease with age, which is often related to or complicated by poor nutrition and eating habits.

Your gastrointestinal tract has approximately 150 times more surface area than your skin, and it contains the largest number of immune cells in your entire body. In fact, your digestive tract comprises about 60% of your immune system. Therefore, maintaining a healthy digestive tract is one of the most important things you can do to stimulate improved immunity to help ward off the cold and flu.

Fiber is crucial to a healthy digestive system. Whole, fresh fruits and vegetables promote a healthy gastrointestinal tract. Fiber promotes the removal of toxins that can adversely affect your gastrointestinal tract cells. This detoxification process will support a healthier immune system.

Vitamins are also essential for a healthy immune system.

Vitamin C supports your body’s immune system and becomes essentially important for upper respiratory viral infections. Adequate levels of vitamin C will promote phagocytic cell and healthy T-cell function.

Excellent sources of vitamin C include foods such as:

  • asparagus
  • kale
  • broccoli
  • cauliflower
  • collard greens
  • beet greens
  • citrus fruits

Vitamin B is another important vitamin for a healthy immune system. There are many different types of B vitamins, each one rendering its own benefit on your body’s defense system. For example, vitamin B5 (pantothenic acid) promotes production and release of antibodies from B-cells, and deficiency of this vitamin results in reduced levels of circulating antibodies. Folic acid, another B vitamin supports the production of red blood cells which carry oxygen through your circulatory system to all parts of your body. All the different B vitamins play an important role in your body’s health and wellness.

Foods containing one or more of the various B vitamins include:

  • romaine lettuce
  • spinach
  • cauliflower
  • cremini mushrooms
  • red bell peppers
  • salmon
  • tuna
  • cod
  • shrimp

Vitamins A, E, and K are also vital for healthy immune system function. You’ll find adequate amounts of vitamins A and/or E in vegetables such as: turnip greens, swiss chard, mustard greens, carrots, sweet potatoes, asparagus, and Bok choy.

Of course, as you can infer from the various food types specified, it’s critical to your body’s immune function to stick to a high plant-based diet, consisting primarily of fresh produce.

Minimizing and even eliminating processed and canned foods from your diet is a good idea to stimulate better health in preparation to fend off seasonal and other contagious threats. You should also consider significantly reducing or eliminating refined sugar from your diet to maximize your immune system function.

As Hippocrates stated, “let food be thy medicine and medicine be thy food”.