Have you ever wondered why foods like oranges are eaten during certain times of the year? While crop and seasonal availability are key drivers, it is also part of supporting wellness during the winter months with cold and flu season thriving. I recently read an article in a nutrition magazine and was bitterly disappointed that the information discouraged people from eating healthy to support the immune system. The article argued that because the immune system in the body is so tightly regulated, it cannot be affected by the foods we eat. I beg to differ! Have you ever felt run-down, knowing you were not eating as healthy as you could? Healthy eating provides the body with everything it needs to support the immune system.
First of all, if you are eating a relatively unhealthy diet, filled with processed foods that contain sugar, salt, fat, and chemicals, your body is probably experiencing some degree of inflammation. This inflammation is a response to high circulating levels of insulin and glucose caused by a high sugar load in those foods in addition to the chemicals commonly found in processed foods. This occurs because of a response by your cells to these substances, creating a cascade of inflammatory compounds being released into circulation. The real problem is that it is occurring everywhere in your body and is compounded by the liver packaging excess sugar into fat stores. That fat is commonly stored in the stomach area and adds to the inflammatory cycle. Having low-grade inflammation greatly influences immune function because the immune system is already working overtime.
Secondly, when eating a diet low in nutritional value, the body becomes undernourished. The vitamins and minerals obtained from a healthy diet provide important pieces that allow for physiological function to occur. Specifically, vitamins C, E, and D and the minerals zinc, selenium, magnesium, and iodine support immune function. Vitamins C and E act as antioxidants, protecting your cells from oxidative stress caused by inflammation related to bacterial and viral infections. Vitamin D supports your immune system while also regulating it to not attack itself as seen in autoimmune conditions. Zinc helps your cells remain healthy, especially those involved in immunity. Selenium not only is involved in immune responses but also enhances insulin sensitivity of cells, in turn affecting blood sugar levels and associated inflammation. Iodine is important for your thyroid gland which regulates your body’s metabolic functions, including immune responses. Magnesium is vital your body’s physiology and is involved in over 300 biochemical reactions, including your immune system. The other important piece that comes from eating healthy food is protein. Protein provides amino acids that are essential when the body is mounting an immune response, and for the creation of antibodies.
Imagine your body working to fight off an infection while maintaining a low-grade level of inflammation due to a poor diet while not having enough important nutrients to support its functions. It certainly begins to make sense of how your immune system can be affected by what you eat. Another benefit to eating healthy is that plant foods contain a variety of plant compounds that act as antioxidants and antimicrobials, supporting your immune system. An orange for example not only contains a high level of vitamin C but also phenolic compounds like flavonoids that act as antioxidants in addition to carotenoids, also with antioxidant actions. While oranges do have fruit sugar, it is balanced by the fiber and micronutrient content making oranges an immune boosting super food.
While there are individual factors involved in each person’s immune response, like stress, genetics, sleep quality, and even relationships, clearly the components that come from the foods we eat can support immunity. By eating a healthy diet rich in whole foods, you provide your body with important pieces to keep you healthy and strong. Plus, by eating healthy, whole foods, you support your gut health where the bulk of your immune system lives. My advice is to eat as healthy as you can each day to support your body and stay healthy in and out of cold and flu season – and remember, an orange is not just an orange!