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To Your Health

Building a Healthy Immune System

A bunch of citrus fruit cut in half

Avoiding illness has been on our minds lately, especially over the last 18 months. A healthy immune system helps protect us from becoming ill, but the question is: Can we strengthen our own immune system? The short answer is yes. However, it’s important to note that no single food or healthy lifestyle behavior can prevent illness. Rather you can only support your immune system by engaging in a variety of healthy lifestyle behaviors.

How our immune system works

Our immune system is quite complex! We were born with innate immunity, the part of the immune system with physical barriers, such as skin, sweat, and the sneeze and cough reflex, to prevent foreign substances from entering the body. If the antigen (foreign substance that triggers an immune response) passes through the innate level, it goes to the acquired or adaptive level. This is where our B-cells are triggered to make antibodies, which with the help from our T-cells, locks onto antigens and destroys them. (B-cells and T-cells are immune cells called lymphocytes made in the bone marrow.) Antibodies can be developed naturally in response to an infection or are developed in a response to a vaccine. Antibodies usually stay in our bodies in case we must fight the same antigen again. However, as immunity may begin to wear off, or as certain viruses can have different strains, such as influenza (also known as the flu), we may need a new vaccine or booster each year.

Eat a healthy diet

Certain vitamins, minerals, antioxidants and probiotics play a critical role in immune function. Eating a variety of foods like poultry, seafood, dark leafy greens, citrus fruits, berries, yogurt, whole grains, and nuts may help foster a healthy digestive tract and immune system. While there are a plethora of herbal remedies and supplements touting immune support, there isn’t much evidence that any of these products do any good. Save your money and instead focus on a healthy balance of nutrient-rich foods, adequate sleep, physical activity and managed stress.

Engage in other healthy lifestyle behaviors

Regular physical activity helps to regulate the immune system. Aim for at least 30 minutes of aerobic activity five days a week and two or more days a week of muscle-strengthening exercises. Sleep is also an essential component to a healthy immune system. During sleep, the body releases cytokines to fight infection and inflammation. Without adequate sleep, the body produces fewer cytokines making you more susceptible to illness. Lastly, when we’re stressed, the immune system’s ability to fight off antigens is reduced. Managing stress isn’t easy, but eating well, being physically active, getting adequate sleep, spending time with friends or family, prioritizing tasks, and perhaps getting help from a qualified mental health professional are all strategies to reduce stress levels. While you can’t always prevent illness from occurring, you can take steps to give your immune system what it needs to do its job.

Join us to learn more

To learn more about how you support a healthy immune system, register to attend University of Illinois  Extension’s “Healthy Behaviors for a Healthy Immune System” September 9 at 10 AM.

Sources:, The innate and adaptive immune system,

Harvard T.H. Chan School of Public Health. Nutrition and Immunity,