9 Proven Ways to Naturally Boost Your Immune System

• The immune system protects the body against external substances that may harm it, like bacteria and viruses, and helps correct abnormal cell growth.
• As we age, the risk of a weaker immune system and autoimmune conditions increases. That said, there are steps to boost immune function at any age.
• Some effective natural immune boosters include eating citrus fruits, getting enough restful sleep, eating a healthy diet, reducing stress, and doing what you can to manage any medical conditions. 

The immune system is your body’s defense against harmful substances that can make you ill. When your body’s immune response works as intended, you probably won’t notice it’s there. When it doesn’t, you may get ill faster or experience more severe symptoms for both short-term illnesses and chronic diseases.

Thanks to the immune system’s important role, it’s normal to wonder what you can do to keep it strong. Here are nine proven ways to boost the human immune system, along with a more in-depth description of what exactly this system is and specific ways to assist it when sick.

Any germ, cellular change, harmful substance, bacteria, or fungi that presents a threat to our health is referred to as an antigen. Each day, we come into contact with a variety of antigens. Some of which can cause illnesses like the flu, COVID-19, the common cold, and other respiratory infections. You may also come into contact with harmful substances in our environment that can induce disease-causing changes within the body, such as the development of abnormal or cancerous cells. 

The immune system is a series of cells, tissues, and organs throughout the body that acts as a safeguard against antigens. This system has many parts, including:

• Skin: a protective barrier to stop substances from entering the body
• Mucous Membranes: a gel-like barrier that helps trap and fight germs within the body
• Antibodies: proteins that assess the threat and attack it in a specified way
• White Blood Cells: fight off harmful substances in a general way
• Lymph System: produces, stores, and transports white blood cells. This system includes bone marrow, the tonsils, the thymus, the spleen, lymph nodes, and lymph vessels.
• Cytokines: chemical messengers that signal the body to help regulate immune system reactions and inflammation in the presence of an infection. Immune cells, including white blood cells, are responsible for cytokine production. There are two types of cytokines: pro-inflammatory cytokines, which increase inflammation when required to fend off harmful substances, and anti-inflammatory cytokines, which stop or lessen inflammation once a substance is gone, so the inflammation doesn’t damage the body.

The Two Parts of the Immune System

This system has two lines of defense: the innate immune system and the adaptive immune system. 

Innate Immune System Details:

• The first line of defense, fighting off intruders with white blood cells. 
• Its role is the same, no matter the threat, so it’s sometimes referred to as the ​“nonspecific immune system.” 
• Your innate immune system includes many types of white blood cells including T cells, which may help fight infections and cancer, and natural killer cells, which target tumors and cells infected with viruses.

Adaptive Immune System Details:

• Takes over if the innate immune system fails to destroy an antigen. 
• Slower to respond because it requires time to recognize what the threat is and then produce specialized antibodies to fight it off. 
• The adaptive immune system has a memory, meaning it remembers germs so that it can fight an infection quicker the second time around. For example, if you get sick with the flu two times in one year, your immune system would be quicker to respond the second time. 

The Importance of Immune Function For Overall Health

Our immune system helps fight off everything from viral infections to cancers. Without effective immune cells, the body is more susceptible to infections from even benign fungi, bacteria, and viruses, creating conditions that may seriously impact quality of life, or even be life threatening. But if the immune system is too active or inactive, it can’t effectively do its job.

When your immune system has difficulty generating an adequate immune response it’s referred to as immunodeficiency. Immunodeficiency diseases weaken the body’s ability to fight off harmful substances. Many of these conditions are genetic, though some, like HIV/​AIDs, aren’t. Some medications, like corticosteroids and chemotherapy, may also decrease the body’s ability to fight disease.

While a weak immune system is cause for concern, overactive immune system function may lead to the body’s immune cells attacking and destroying healthy tissue. There are over 80 diseases that fall into this group, and collectively, they are referred to as ​“autoimmune disorders.” A few common ones are Rheumatoid arthritis, multiple sclerosis, Celiac disease, Graves’ disease, and inflammatory bowel disease (IBD). 

Immune System and Age

The aging process can weaken your immune system. Age-related changes that may impact your immune system include: 

• Higher risk of developing an autoimmune disease
• Slower immune system response
• Slower healing process since aging sometimes results in fewer immune cells
• Declined ability to detect and correct cell abnormalities, increasing the risk of cancer

These changes aren’t guaranteed to happen, and there are steps anyone can take to enhance immune function, which we’ll detail below. 

Your day-to-day decisions and habits affect immune function. Ahead are nine strategies that enhance immunity, as well as overall health. 

1) Get Enough Sleep

When we sleep, the body uses that time to repair any damage to our cells, boosting our innate immune function. Getting adequate sleep (seven to nine hours for most adults) has been linked to better immune function, while there is a correlation between sleep deprivation and a weakened immune system. 

Tips for a good night’s sleep include:

• Go to bed and wake up at the same time, even on weekends to balance your circadian rhythm
• Sleep in a cool, dark environment
• Move your body since physical activity during the day makes it easier to sleep
• Do a relaxing activity right before bed, such as reading a good book or taking a warm bath
• Avoid phones, TVs, and other screens for 30 minutes to an hour before sleeping
• Limit alcohol consumption and avoid heavy meals in the evening

2) Eat Citrus Fruits and Other Fresh Fruit

Eating fruit is a great way to improve immune function. Citrus fruits and juices in particular contain ingredients like folic acid, vitamin D, and vitamin C, which sustain the function of many immune cells. Other fruits like tomatoes contain beta carotene, which also supports immune function. Fruits with vitamin E, like mango and kiwi, possess anti-inflammatory effects and help with immune function as well.

The best fruits for immune health include:

• Oranges
• Berries
• Tomatoes
• Mango
• Kiwi
• Lemons
• Grapefruit
• Tangerines
• Lime

3) Eat An Overall Balanced Diet

Fruits aren’t the only nutritious foods that support immune function. Other healthy foods that boost immune health are:

• Leafy green vegetables: Plant foods, especially darker green veggies like kale and spinach, contain high amounts of vitamin C and antioxidants, which help fight infection.
• Whole grains: Quinoa, brown rice, and other whole grains have anti-inflammatory effects, which may help the immune system respond faster.
• Fish: The fish oil in fatty fish like salmon and tuna have high levels of omega‑3 fatty acids, which increase white blood cell activity. If you don’t get enough from your diet, a supplement with omega‑3 may offer similar effects.
• Poultry: Lean chicken and chicken soup are high in vitamin B‑6, which can help with immune function.
• Brightly colored veggies: Vibrant veggies like peppers and carrots also contain high levels of essential nutrients for the immune system, like beta carotene and vitamin C.

Research suggests that 70–80% of immune cells are found in the gut. While focusing on certain foods like the ones above is a good goal, it’s also important to eat a balanced, healthy diet that supports gut health. The immune system may also work better when alcohol consumption is lower and when there are fewer highly processed foods, like potato chips or cake, on your plate. 

4) Consider Dietary Supplements

If you can’t get enough essential nutrients from diet alone, consider dietary supplements and vitamins. Depending on their ingredients, these may help strengthen your immune system, but it’s important to speak with your doctor before taking any vitamins or supplements to ensure they’re good for your health and do not interfere with your medication regimen. 

Specific ingredients to look out for in an immune health supplement include:

• Folic acid
• Vitamin C
• Vitamin D
• Magnesium
• Zinc
• Selenium 

5) Do What You Can to Fight Infection

Healthy eating and an overall healthy lifestyle can strengthen immune functioning, but healthy living also includes taking steps to reduce your chance of contracting infectious diseases. These include:

• Washing hands often
• Preparing food carefully to avoid foodborne illnesses
• Being careful around wild animals. Clean a wound and seek medical help if bitten by an animal.
• Wearing insect repellent when in an area with mosquitoes and other bugs that carry disease
• Following safe sex practices to prevent HIV/AIDS and other sexually transmitted diseases

Getting the recommended vaccines for your age group and attending all doctor’s appointments, including your annual physical, are also paramount to prevent illnesses and manage any chronic conditions. At these appointments, a healthcare provider may conduct a blood test to assess the level of immune cells in your body, take your body weight to determine if it’s within a healthy range for your age, height, and body habitus, and perform other measurements of overall health. From there, they can recommend personalized ways to improve your immune health. 

6) Reduce Stress

Managing stress is also important since high levels of psychological stress disrupt immune function, meaning your body isn’t able to fight off diseases as intended. Some effective ways to minimize stress include:

• Breathwork
• Meditation
• Journaling
• Yoga
• Walking
• Gratitude journaling
• Self-care activities such as a nice bath, a moisturizing routine, or finding a good therapist

If stress levels are difficult to manage on your own, consider working with a mental health professional, such as a therapist or psychiatrist, who can provide more robust support for your mental health. 

7) Manage Any Health Conditions

Successful management of conditions like arthritis, high blood pressure, or diabetes means immune cells spend less time fighting off these chronic conditions and can better address other threats to overall health. Individuals who have any of these conditions should work with the appropriate health professional to create a treatment or management plan—and should follow that plan.

To boost the immune system naturally, it’s best to engage in balanced, gradual changes that often bring about more sustainable improvements. 

If wondering where to start, here are a few small changes that may help:

• Book a preventative health screening with a provider
• Spend five minutes a day on a stress-reducing activity
• Add one immune-boosting food to your plate this week

For more advice on making a habit change stick, visit this resource.

Many of the above tips are lifestyle changes to make your immune system healthier in the long run. If you are currently sick, these tips are still useful, though they may not ease symptoms right now.

Some ways to improve immune function when sick include:

• Give your body plenty of time to rest
• Avoid alcohol, sugar, or smoking
• Hydrate with water and sugar-free tea
• Eat foods that are high in vitamin C, or consider taking a vitamin C supplement

If symptoms can’t be managed with over-the-counter medications and rest, see a healthcare professional. They can assess symptoms, prescribe any necessary medications, and may even help speed up recovery.