Let’s Talk Nutrition: Nutrition for a Healthy Immune System
Inflammation – people talk about it like its public enemy #1! Actually, inflammation is a normal process in our bodies that helps to fight off invading germs and repair damaged tissues. It is an incredibly orchestrated defense system that is amplified or dampened by chemical switches that come from hormones, fatty acids, and other substances.
White blood cells release cytokines that stimulate changes within the body that help to eliminate the toxin - like fever or runny nose. Destructive enzymes are released to kill off the germ. Normally, inflammation is short-lived. After an infection is over, cytokine levels go back to normal.
Trouble is, our diet, environment and state of mind often give our immune system a false signal to go into “fight” mode. Endocrine disruptors like pesticides and plastics can promote inflammation. Eating a high sugar diet causes elevated insulin levels, which can activate inflammation. A diet with more proinflammatory fatty acids, can also lead to prolonged inflammation. A little extra weight around the middle? Belly fat releases cytokines….even when there is no cold bug, no flu, and no injury. Even chronic stress, combined with a sense of hopelessness, as well as sleep deprivation, can lead to increased cytokines. Lack of sunlight has caused a widespread deficiency of vitamin D, necessary for regulation of the immune system. Thus, inflammation from our lifestyle becomes a constant, low grade “attack” within the body. With no actual germ present, our healthy tissues take the hit. Chronic inflammation is at the root of many conditions – heart disease, cancer, Alzheimer’s disease, Parkinson’s disease. Depression and Autism also have inflammation as a part of the picture.
We can naturally support our immune system with a plant-based, low fat diet (that includes enough good fats!). Plant foods support a healthy immune system by stimulating immune cells to grow and to function optimally, to regulate the immune response, and to protect healthy tissue from damage.
Increase these healthy foods to support your immune system:
Eat orange-yellow fruits and veggies like yellow squash, sweet potatoes, and carrots to increase beta-carotene, the phytonutrient that helps to form vitamin A. Spinach is another source. Vitamin A helps immune cells become specialized so that you are prepared to fight an infection. Vitamin A deficiency can lead to an impaired immune response.
Green tea and pomegranate appear to modulate the immune system, helping to normalize an over-reactive or sluggish immune response.
Seeds, nuts and raw wheat germ, contain vitamin E, which floats in cell membranes and acts as a primary defense against free radical damage. In the process of fighting free radicals, vitamin E is changed (oxidized) and becomes ineffective. Vitamin C found in broccoli, kiwi and citrus fruits, helps restore the potency of vitamin E so that it can continue to fight free radicals.
Cranberry and blueberry juices are especially good sources of antioxidants. Antioxidants defend against cell damage by free radicals released during an infection and the inflammatory defense that follows. When antioxidant levels are low, free radicals can damage healthy tissue.
Brazil nuts, wheat, corn and oats provides selenium, a powerful antioxidant. Selenium influences the genetics of pathogens and helps improve resistance to infections. Selenium deficiency leads to slowing of the immune response, and a greater level of free radicals.
Flax seeds, soy, and a plant-based diet help increase HDL, the good cholesterol. HDL seems to enhance immunity. In addition, the omega 3 DHA, found in perilla plants and blue-green algae, aids in chemotaxis, helping white blood cells locate and destroy invading pathogens. Trans fats cause good cholesterol to drop, contributing to a decline in immune function.
Probiotics, beneficial bacteria found in fermented foods like soy or coconut yogurt, enhance immunity by helping to maintain good cholesterol levels and prevent bacterial infection.
Olive oil, avocado and almond butter provide good fats that aid in the regulation of the immune system. A high fat diet, especially including trans fats, tends to slow the immune response. A good balance for the immune system is to avoid fatty fried foods and trans fats, instead eating a low fat diet that includes foods containing good fats. Maintaining a normal body weight helps to keep the immune system responsive.
Sesame seeds and almonds contain zinc, a mineral that helps killer T-cells to mature. Omega 3 fatty acids, found in seeds and nuts, also can ramp up Killer T-cell function. Zinc deficiency can slow down the ability of the immune system to respond.
With healthy food, you can support your immune system. Increase fruits and veggies, go easy on fats, and drink green tea and high-antioxidant juices. Be sure to also get the immune enhancing effects of a good night’s sleep, practice relaxation, and get plenty of vitamin D from sunlight.