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From the common cold to life-threatening diseases, our immune system acts as our body's mighty defender to keep us healthy. While our immune system works tirelessly to keep us well, there are steps we can take to strengthen and support it.


September 18, 2023

In today’s fast-paced world, maintaining good health is more important than ever. By adopting a few simple yet effective habits, you can boost your immune system's defenses and lower the risk of falling ill. In this blog, we will take a closer look at the immune system, how it functions and explore a range of healthy habits to support it.

How Does the Immune System Work?

The immune system is your body's defense against germs and viruses – also known as pathogens. It works tirelessly to protect you from getting infections and helps you recover when you do get sick. The immune system is made up of different cells, tissues, proteins and organs that work together to defend our bodies against pathogens.

Types of Immunity

father holding daughter while she shows him her arm muscle
  • Innate Immunity: You are born with this. This is the body’s natural, built-in defense system that provides immediate protection against pathogens without prior exposure. Some examples of our innate immune system in action include:1,2
    • Tears and Saliva: Have you ever wondered why your eyes tear up when something is in them? Tears contain antibodies that can wash away and kill certain pathogens. Saliva in your mouth also helps fight off harmful bacteria.
    • Fever: When your body detects pathogens, it raises your temperature to create an environment that helps prevent the growth and replication of those germs. Therefore, it’s common to experience a slight fever when you’re sick.
    • Inflammation: When you get a cut or a bruise, you may notice redness, swelling and heat in the affected area. That is your body at work. Inflammation is like an alarm system that signals the immune cells to rush to the site or injury to help eliminate pathogens and begin healing.
  • Active immunity: Your body’s immune system actively fights off a pathogen, either because you were infected by it or received a vaccine. This leads to the production of specific defenses to protect you from future encounters with the same pathogen. Examples of this in action include:
    • Catching a Cold: Once you recover, your body is ready to quickly recognize and fight off the same cold or virus if you come across it again in the future.
    • Vaccination: When you receive a vaccine, your immune system is exposed to harmless parts of the virus or weakened forms of the virus. Your immune system recognizes this and responds by producing antibodies that help defend or reduce the severity of the illness if you come down with it.
  • Passive immunity: This happens when you receive antibodies instead of making them through your own immune system. Examples of this include:
    • Maternal Antibodies: Newborn babies have antibodies from their mothers. This kind of immunity gives you protection right away. But it only lasts a few weeks or months.
    • Infused Antibody Cocktails: Monoclonal antibody infusions that are given for COVID infections to those at highest risk for severe complications from the disease. These keep at risk individuals from ending up on a ventilator or worse.

Factors Influencing Immunity

Several factors can impact the strength and efficiency of our immune system. Genetics, age, lifestyle choices and environmental factors all play a significant role. While some factors are beyond our control, there is no magic pill that can instantly enhance our immune system. However, there are lifestyle choices we can make to enhance our immunity and protect ourselves.

Ways to Boost Your Immune System

woman making smoothie
  1. Maintain a Nutrient-Rich Diet: The immune system can be weakened by poor nutrition, yet it can be boosted with vitamins C, E and beta-carotene. Although taking supplements can provide these essential vitamins and minerals, it is even more beneficial to get them from natural sources, such as fruits, vegetables and superfoods.3 Learn about summer superfoods and winter superfoods.
  2. Prioritize Sleep and Rest: Sufficient sleep is essential for a strong immune system. Aim for seven to eight hours of quality sleep each night. Your body uses less energy when you sleep so that cells resupply for the next day. To help prepare for a good night’s sleep, try creating a relaxing bedtime routine, such as avoiding electronic devices before bed, creating a calm sleep environment and practicing relaxation techniques like meditation or gentle stretching. Remember that rest and relaxation during the day are also beneficial for maintaining immune health.
  3. Stay Active and Exercise: Regular physical activity helps boost your immune system and overall well-being. Engage in moderate-intensity exercises like brisk walking, jogging, cycling, or indoor activities like yoga or home workouts. Aim for at least 150 minutes of exercise per week. If outdoor exercise is challenging during winter, consider indoor alternatives like joining a fitness class or using workout videos.
  4. Practice Good Hygiene: Good hygiene habits are essential to help avoid getting sick. Remember to scrub your hands with soap and water for 20 seconds, particularly before eating or touching your face. If soap and water aren't available, use hand sanitizer. Stay away from anyone who's sick and cover your mouth and nose with a tissue or your arm when you cough or sneeze.
  5. Boost Your Vitamin D Levels: During the winter season, sunlight exposure decreases, leading to lower vitamin D levels in the body. Adequate vitamin D is essential for immune function. Try to spend time outdoors during daylight hours, exposing your face and arms to natural sunlight. Learn how to increase your vitamin D without the sun.
  6. Manage Stress Levels: Chronic stress can weaken your immune system, making you more susceptible to infections. Incorporate stress management techniques into your routine, such as meditation, deep breathing exercises, mindfulness or engaging in activities you enjoy. Prioritize self-care and allocate time for relaxation and stress reduction.
  7. Stay Hydrated: Staying hydrated plays a vital role in boosting immunity. Proper hydration supports the optimal functioning of the immune system, enabling it to effectively defend against harmful pathogens. When you're adequately hydrated, immune cells can move freely throughout the body, improving their ability to reach infection sites quickly.
  8. Consider Flu Vaccination: Consult your health care provider about getting an annual flu vaccine. Influenza can be severe, and vaccination provides an additional layer of protection. The flu vaccine is typically recommended before the onset of flu season, so schedule your vaccination accordingly. Learn more about flu shots.

Nurturing a strong immune system is a lifelong commitment to your health and wellbeing. By adopting healthy practices like eating a balanced diet, regular exercise and managing your stress, you can help strengthen your immune system. Remember, immunity is not an overnight achievement but rather a lifelong commitment to a healthy lifestyle. So, take the time to take care of yourself and your body's natural defenses.


1 National Library of Medicine: Immune System and Disorders. Last updated August 17, 2020. Accessed July 11, 2023.

2 CDC: Immunity Type. Last Updated September 24, 2021. Accessed July 11, 2023.

3 CDC: Defining Powerhouse Fruits and Vegetables. June 05, 2014. Accessed July 11, 2023.

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