How to Build a Healthy Immune System

Your immune system is your primary line of defense when viruses and illness strike. Like any strong defense system, it needs a leader to command the forces. In this case, that leader is you. Many of us think about strengthening our immune system during cold and flu season. But you can adopt habits year-round to build a healthy immune system that's prepared to fight the good fight.

Understanding the Immune System

Your immune system is a complex system of cells and organs that defend the body against harmful invaders like bacteria, viruses and parasites.

According to the National Institutes of Health, your skin and mucus are among your first lines of defense; they try to keep disease-causing germs out. When germs get past those outer defenses and enter your body, B-cells, a type of white blood cell, release antibodies to attack the germs. Another type of white blood cell — T-cells — attacks germs directly and produces cytokines that regulate the whole immune system's response.

While your immune system is launching an attack, you may experience inflammation, fever, fatigue, cough, sore throat or other signs that you're sick. These symptoms are important immune mechanisms that help your body fight off disease. Inflammation, for instance, releases chemical messengers that cause white blood cells to flock to where there's swelling and eat germs and damaged cells.

Once your immune system has have killed off the invading germs, they develop antibodies that are specific to those attackers that stay in your body long after the immediate threat is gone. These antibodies can recognize when the same germ comes back and fight it off from the start with a more targeted attack.

How to Build a Healthy Immune Base

Chronic illness, age and your daily habits affect the strength of your immunity. But you can take steps to promote a healthy immune system.

• Eat your fruits and veggies. Get at least five servings of fruits and vegetables daily. Fresh produce contains a wealth of vitamins and minerals your body needs to keep those white blood cells ready for action. One method is to eat a variety of fruits and vegetables of diverse colors to cover all your bases — Harvard Medical School reports that different colors signal the presence of different nutrients.
• Include omega-3 fatty acids.Foods such as salmon, flax seeds, chia seeds and walnuts are rich in omega-3s. These healthy fatty acids act on white blood cells to reduce inflammation and strengthen your body's immune response, according to research in the International Journal of Molecular Science. The U.S. Department of Health and Human Services recommends eating about 8 ounces of seafood a week to ensure adequate omega-3 consumption.
• Get probiotics in your diet. According to research in Cell, gut bacteria play a huge role in producing white blood cells, triggering your body's response to harmful substances and fighting off invaders. The more diverse your gut bacteria are, the more likely it is they can support the gut's immune system to mount a successful defense. Consuming probiotics introduces live strains of bacteria into your gut, which helps to keep your gut bacteria diverse and healthy. You can get them through daily supplements containing Lactobacillus and Bifidobacterium species or by eating fermented foods like kimchi and yogurt a few times a week.
• Exercise regularly. You don't have to be an Olympic athlete to reap the benefits of exercise. Consistent, moderate physical activity — about 30 minutes per day — helps your immune system track down and kill germs and slow the immunity-suppressing effects of aging, according to the University of Bath.

• Get plenty of sleep. Getting regular sleep, at least seven hours a night, strengthens your white blood cells. The Rockefeller University Press found that disease-fighting T cells were more effective in people who got enough sleep.
• Relax and unwind. When you're chronically stressed out, your immune system suffers. The Cleveland Clinic explains that stress leads to ongoing inflammation, which puts you at risk of immune-related illnesses like arthritis. Take time daily for at least 10–20 minutes of deep breathing, meditation, yoga or any activities that help you relax. Guided meditation apps such as Ten Percent and Calm can help you get started.

Everyone's immune system is different. Your lifestyle habits, genetics and unique physiology influence your body's immunity. If you're unsure where to begin or you've struggled to find an exercise routine or food plan that fits your lifestyle, a health coach can help.