The immune system serves as your best defense against viruses and illnesses like colds and flu. In its best working state, it destroys sinister invaders, like viruses and bacteria, that threaten your health. Your immune system even protects against cancerous tumors by launching an immune response against cancer cells before they gain a foothold in the body.
What exactly is the immune system? It comprises various cells and chemicals that protect the body from infections, both from outside invaders that enter the body. You probably aren’t surprised to learn that lifestyle factors can impact how efficiently your immune system functions. If you eat a poor diet, smoke, and get 4 hours of sleep per night, your immune system can’t do its job as efficiently, and you may pay for it with illness.
What can you do to keep your immune system healthy? A healthy lifestyle is one of the best ways to boost your immune system. Luckily, there are plenty of things you can do to keep your immune system functioning at its best. Consider these five immune boosters:
Reduce the Amount of Sugar in Your Diet
Sugar is empty calories, but it also reduces your immune system’s ability to fight infection. A study found that rapidly absorbed carbohydrates, including sugar in its many forms, suppress the phagocytic activity of neutrophils. In other words, neutrophils, cells in the blood can’t take up and inactivate viruses as easily.
However, a diet rich in fruits and vegetables and low in ultra-processed foods helps optimize immune health. The take-home message? Cut back on sugar, refined carbohydrates, and junk food. Not only might these foods suppress immune function, they also lack the nutrients your body needs for immune health.
Get Enough of the “Big Three” for Immune Health
Although you need many nutrients and micronutrients for a healthy immune system, three vitamins and minerals play a key role in immune health. These are vitamin C, vitamin D, and zinc. Getting enough of these vitamins is critical for immune health.
Vitamin C is an antioxidant vitamin that supports immune health by enhancing the function of immune cells and keeping the barriers that protect against infection healthy. Vitamin C also helps clear out old or defective immune cells, like neutrophils, from the system. The best sources are raw fruits and vegetables since heat and light destroy vitamin C.
Vitamin D helps balance the immune system. Studies show low vitamin D increases auto-immunity, may worsen autoimmune diseases and boosts susceptibility to infection. The best source of vitamin D is UVB rays from the sun. Food is not a reliable source, except for eggs, fatty fish, mushrooms exposed to sunlight, and foods fortified with vitamin D. Since so many people have low to borderline low levels of vitamin D, checking a level with a blood test is helpful. If you’re low, you may need a supplement.
Zinc plays a key role in wound healing and immune function. Research shows it helps develop immune cells and supports their healthy function. Studies also show zinc has anti-viral activity. Zinc is most abundant in meat, shellfish, beans, lentils, nuts, seeds, dairy, eggs, and whole grains. People who eat a vegan diet may have low zinc levels since meat and dairy contain higher levels of absorbable zinc.
Change Your Sleep Habits
Sleep is like nourishment for your immune system. Unfortunately, most people don’t get enough of it. Many people fall short of the recommended 7 to 8 hours of sleep per night. When you skimp on sleep or have poor-quality sleep, it raises cortisol, a stress hormone that suppresses immune function.
Another problem is going to bed too late. For healthy immune function, turning in as soon after sundown is optimal for properly setting your internal biological clock. When your internal clock is properly set, your immune system functions at its best. Expose your eyes to natural light as early in the morning as possible, and avoid exposing your eyes to light, especially blue light from technology, in the evening.
Mental and physical stress both cause a rise in cortisol and interfere with healthy immune function. That’s why it’s important to have practical ways to manage stress. Mindfulness meditation is one option. A study found that meditation altered the expression of thousands of genes that affect the immune response, stress, and how the body responds to viruses. If meditation isn’t your thing, yoga, stretching, deep breathing exercises, warm baths, and walks in nature help with stress management.
Do the Right Amount of Exercise
Exercise, in moderation, enhances your health, and research shows doing it in moderation can boost the health of your immune system. Avoid overtraining though. Too much exercise, like training heavily for a marathon, can raise the stress hormone cortisol and reduce stymie immune function. Studies show marathoners are more likely to suffer from the common cold and other upper respiratory viruses within 14 days after their big run.
Exercise most days of the week for 30 minutes to an hour, but give your body rest and recovery time afterwards. Have a snack that contains carbohydrates and protein after a workout. Supplying your body with carbohydrates after a sweat session helps lower cortisol, a hormone that reduces immune function.
The Bottom Line
Your immune system is made up of an army of cells designed to protect your body from foreign invaders, including bacteria, viruses, and other invaders. But this immune army depends on you leading a healthy lifestyle to function at its best. Make sure you’re supporting it.
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- com. “New Clues Into How Meditation May Boost The Immune System”
- com. “Does Sugar Weaken the Immune System?”