How to Boost My Immune System - Updated 2023

Your immune system protects your body against infection and disease, fighting everything from flu viruses to cancer. Maintaining a strong immune system is critical for overall health and well-being. This article will walk you through five strategies to boost your immune system at home:

1. Get plenty of sleep
2. Eat a healthy diet
3. Manage stress
4. Exercise regularly
5. Avoid smoking and drinking alcohol

Get Enough Sleep

The CDC recommends that adults sleep around 7-9 hours every night. People who get under 6 hours of sleep per night are almost 3 times more likely to catch a cold than those who sleep 8 or more hours. Quality of sleep is essential. People with less efficient rest were 5.5 times more likely to catch a cold than those with better quality sleep.

Sleep deprivation can put your body in a chronic inflammatory state, leading to fatigue, fever, and joint pain. Besides simple colds, these can exacerbate serious cardiometabolic, cancerous, autoimmune, and neurodegenerative diseases. 

How Can I Get Better Sleep?

Getting good sleep can be challenging in our modern age of smartphones, work demands, and social demands. Here are some tips to improve the quality and duration of sleep:

• Consistency – Sleep and wake up around the same time every night and morning, even on weekends. Ask your friends and family to keep you accountable.
• Sleep-friendly environment – Ensure your bedroom is quiet, dark, and comfortable. Remove all electronic devices, including TVs, computers, and smartphones.
• Avoid heavy foods before bed – Before going to sleep, do not eat heavy meals, consume alcohol, or consume caffeine.
• Exercise – Be physically active during the day to fall asleep faster at night.

Eat a Healthy Diet

Eating a well-balanced diet rich in vitamins, minerals, antioxidants, and other essential nutrients is crucial for supporting immune function. Undernutrition and malnutrition can impair immune system function, making fighting off infections like colds or flu viruses difficult. The duration of colds is reduced by 8% among adults who ingest vitamin C regularly. Among children, 1 to 2g of vitamin C per day shortened the duration of colds by 18%.

Some key micronutrients essential for immune system function are outlined in the table below.

Sources: Mayo Clinic, BMJ

How Can I Maintain a Healthy Diet?

Diet cannot cure illness but can aid your immune system in recovering quickly. Eating three balanced meals every day is critical. Here is a list of foods that boost your immune system by providing necessary daily micronutrients:

• Fatty fish are rich in healthy fats, vitamins D and B, iron, and zinc.
  • Albacore tuna
  • Herring
  • Mackerel
  • Salmon
  • Trout
  • Sardines
• Citrus fruits are rich in vitamin C.
  • Oranges
  • Lemons
  • Limes
  • Grapefruits
  • Bell peppers (though not a citrus fruit, they contain more vitamin C than an orange!)
• Green leafy vegetables are rich in vitamins A, C, and E.
  • Broccoli
  • Spinach
  • Kale
  • Chard
  • Collard greens
  • Arugula
  • Bok Choy
• Yogurt contains probiotics that keep your gut healthy.
• Snacks like almonds and sunflower seeds are rich in vitamin E.
• Whole grain bread is high in fiber, which aids immune and digestive health.

Doctors often recommend eating a “Mediterranean diet,” which emphasizes eating fruits, vegetables, legumes, and whole grains, while avoiding processed foods, dairy, and red meat. 

Manage Stress

Stress kills immune cells called lymphocytes, which are needed to fight viruses. Research has shown that chronic stress produces higher levels of the hormone cortisol. Cortisol can lead to a greater risk of depression, cardiovascular disease (CVD), diabetes, autoimmune diseases, and poor wound healing. Like sleep deprivation, stress puts your body in a chronic inflammatory state, increasing susceptibility to colds and upper respiratory infections.

How Can I Manage My Stress?

The following list describes ways to combat stress for better mental health and a more robust immune system. Not every strategy might work for you, but you can use trial and error to determine the most helpful.

• Practice mindfulness – Practice meditation, deep breathing, and journaling.
• Connect with loved ones – Stress can make socializing hard, but investing time into your social support system can improve your self-esteem and decrease stress levels.
• No more negative self-talk – Train your inner monologue to be kinder, gentler, and more forgiving. Replace negative thoughts with positive ones to help you cope with challenging periods.
• Engage in your hobbies – Make time for pursuits and activities that bring you joy.
• Go for a walk – Research has shown that a 90-minute stroll outdoors can help reduce negative thoughts.

Get Regular Exercise 

Two hours of moderate exercise per day can lead to a 29% reduction in the risk of contracting an upper respiratory tract infection (URTI). Physical fitness and aerobic exercise are correlated with reduced duration of URTI and severity of cold symptoms during the fall and winter. 

Exercise helps lower stress by pumping your brain with endorphins, neurotransmitters that increase feelings of well-being. Endorphins enable a lasting presence of immune cells, providing extra time for the immune cells to keep your body safe from pathogens. 

It should be noted that high-intensity strenuous exercise can actually decrease immune function, so make sure not to over-exert yourself.

How Do I Engage in More Exercise?

Aim for around 120-150 minutes of moderate exercise per week. You can include strength training twice a week. Choose activities that you enjoy so it is easier to be consistent. Here are some examples of moderate to vigorous and strength exercises to incorporate into your daily routine:

Sources: Harvard, Mayo Clinic 

Avoid Tobacco and Alcohol

Stop Smoking

Smoking impairs immune function and correlates with a higher incidence of respiratory infections. Smokers have double the risk of contracting pneumonia compared to nonsmokers. Furthermore, smokers are 50% more likely to have more severe COVID-19 symptoms.

Tobacco use is also a significant risk factor for non-infectious diseases like chronic respiratory disease, cancer, diabetes, heart disease, and stroke. It is the underlying cause of death in about 90% of tracheal, bronchus, and lung cancer cases worldwide. Therefore, smoking does not only make it harder to fight off infections, but it also increases your risk of contracting chronic illnesses. 

Limit Alcohol Consumption

Your body treats alcohol like toxins, which overworks your immune system. Excessive alcohol increases your susceptibility to contracting pneumonia and acute respiratory stress syndromes (ARDS). People who abuse alcohol are 10 times more likely to develop bacterial pneumonia and 4 times more likely to die as a result than non-drinkers. Alcohol drinkers are also 3 times more likely to suffer from ARDS.

Like tobacco usage, alcohol can also increase your risk of non-infectious diseases like hypertension, cardiovascular disease, liver disease, cancer, and pancreatitis. It can lead to neurological and mental health disorders like depression, anxiety, and substance abuse.

How Can I Avoid Tobacco and Alcohol?

Stopping tobacco usage can be difficult, but the resulting health benefits for your immune system are almost immediate. The table below outlines some short-acting therapies you can try to quit tobacco products.

Source: Mayo Clinic, Drugs.com 

Alcohol sobriety has significant positive impacts on your health. It improves your quality and duration of sleep, reduces chronic inflammation in your gastrointestinal (GI) tract, and unburdens your immune system from needing to flush the alcohol out of your body. These all boost overall immune function. Here are some strategies to avoid alcohol: 

• Limit alcohol consumption to one drink per day for women and two drinks per day for men.
• Find support among family members and friends to keep you accountable.
• Manage triggers that might prompt you to drink, like happy hour events or nightclubs.
• Remove alcohol products from your home.

Boosting My Immune System: FAQs

This section will answer frequently asked questions about boosting your immune function.

Should I take supplements to boost my immune system?

The average healthy American actually does not need extra vitamins to keep their immune system healthy. We would recommend simply continuing to eat healthy and exercise. However, if you are looking to purchase supplements, here are some micronutrients to focus on:

• Vitamin D
• Vitamin C
• Zinc
• Vitamin B-12 and B-6
• Selenium
• Garlic
• Elderberry

Does too much exercise harm my immune system?

Although moderate exercise improves immune function, research has shown that strenuous exercise can suppress immunity and increase the risk of infections like URTI. As such, it is crucial not to overwork yourself and respect your body’s limits during exercise. Stay hydrated and get plenty of sleep when engaging in physical activity.

What foods should I avoid to help my immune system?

Avoid foods that can cause inflammation, such as

• fast food, junk food, and foods with added sugars;
• trans fats found in fried and processed foods;
• refined carbohydrates found in white bread, pasta, and pastries;
• processed meats like hotdogs and sausages; and
• red meat.

How do vaccines help my immune system?

Vaccines train your immune system to be smarter and stronger. Your immune system recognizes and neutralizes foreign or harmful substances in your body, like bacteria, viruses, fungi, and cancer cells. 

Vaccines are crucial for helping your body prepare to fight off infections like the flu or COVID-19. By learning what a disease looks like through a vaccine rather than the actual pathogen, your body can safely learn how to recognize it and better fight it off in the future. Vaccines help stop the spread of infectious diseases, ensuring entire communities can be safe and healthy.

Does body weight affect immune function?

Regular exercise and a healthy diet go hand-in-hand with maintaining a healthy weight. Obesity can lead to poor immune system function by reducing antibody production and impairing immune cells. As such, people struggling with obesity are at a higher risk of bacterial, viral, and fungal infections and have poor responses to vaccines. Unfortunately, they also take longer to recover from infections. 

Bottom Line

Your immune system is a remarkable defense mechanism that shields your body from harmful pathogens and reduces the risk of infectious diseases. Maintaining a strong immune system is essential for overall health, well-being, and happiness. Try incorporating the following tips into your daily life to boost immune function:

1. Prioritize sleep – Aim for a consistent 7-9 hours of sleep each night.
2. Eat a healthy diet – Include fruits, vegetables, whole grains, lean proteins, and healthy fats in your meals.
3. Manage stress – Practice stress management, such as meditation, journaling, or engaging in hobbies.
4. Engage in regular exercise – Moderate aerobic and strength training exercises are key to maintaining immune function.
5. Avoid smoking and drinking alcohol – Quit smoking and limit alcohol intake to reduce the risk of respiratory infections and other diseases.