Our immune systems help keep us healthy and defend our bodies when we encounter pathogens. With flu season in full swing, it’s a great time to boost your immune system. 

We’ll show you how our immune system works and how to keep it healthy. So get comfortable and keep reading with us. 

How Does Our Immune System Work?

Your immune system’s job is to protect the body from harmful substances called antigens. Antigens can be any foreign substance to your body, including:

  • Germs
  • Chemicals
  • Drugs
  • Foreign particles (i.e., splinters)

Germs are usually proteins found on the surface of cells. These can include bacteria, viruses, and fungi. Certain germs will only make you ill the first time you contact them, mostly childhood illnesses like chicken pox.

Two subsystems within the immune system are closely linked and work together whenever an antigen is detected. These are known as the innate and adaptive immune systems.  

The innate, or non-specific, immune system defends the body against harmful germs and substances using cells called Phagocytes. These cells “eat” any foreign substances that enter the body. 

The innate immune system is the immune system you are born with. Besides the cells that eat foreign substances, it also uses barriers to keep antigens from entering your day in the first place. Some of these barriers include the following: 

  • Cough reflex
  • Enzymes in tears and skin
  • Mucus
  • Skin
  • Stomach acid

The adaptive, or specific, immune system makes antibodies that fight germs that the body has previously come into contact with. Because of this, you may hear this system referred to as the “learned” immune system. The adaptive system can also fight bacteria or viruses that change over time, like the flu. 

The adaptive immune system develops over time as it’s exposed to antigens. This is what allows it to build a defense against that specific antigen. 

The immune system also includes white blood cells and chemicals and proteins in the blood. Some of these work to directly attack foreign substances, while others work to help the immune system cells.

Diet Changes to Boost Your Immune System

Doctors recently developed the theory that 80% of our body’s immune system starts in the gut. So it goes without saying that your diet will significantly affect your immune system strength. 

There are several different aspects to having a healthy diet, and certain foods and vitamins are believed to help boost your immune system. 

Immune Boosting Foods 

Including fruits and vegetables in your diet is a great way to boost your immune system. Including a variety of them ensures you get the nutrition you need to stay healthy.

Dark leafy greens are rich in vitamin C along with antioxidants and beta carotene. Add some of these to your daily intake: 

  • Spinach
  • Kale 
  • Collard greens 
  • Arugula 
  • Swiss Chard 

Fatty acids help stimulate white blood cell activity and fight off infections. You can get these through fish oils found in tuna, salmon, and mackerel. If you are not a fan of fish, you can also get your daily dose in supplements

Berries are full of vitamins and nutrients that help boost your overall health. They also make an excellent substitution for sugary snacks when you have a sweet tooth. 

You’ve probably heard that citrus can help you get over a cold or mild flu. This is because it increases your white blood cell count helping to decrease inflammation and maximize your immune systems response time. Citrus also gives your body an extra boost of vitamin C. 

Lean meats like chicken are high in vitamins and minerals that help aid the production of red blood cells and white blood cells. They are also typically low in fat, helping you keep your weight under control. 

Vitamins B6, C, E, Zinc, and magnesium are some of the best vitamins and minerals to help boost your immune system. However, some vitamins may be harmful if taken in excess, be sure to talk to a doctor before adding any to your diet. Try adding some vitamins to your diet naturally with these other immune-boosting foods: 

  • Yogurt 
  • Kombucha
  • Sour Kraut 
  • Mushrooms
  • Watermelon
  • Broccoli
  • Dark Chocolate
  • Sweet Potatoes
  • Chickpeas
  • Bell pepper

Drinking Water 

Drinking water and staying hydrated are essential to keeping your immune system healthy and functioning correctly. While the amount of water you should’ve drinking varies from person to person, the average recommendation is about 64 ounces per day. 

If you struggle with drinking water, aim to drink a glass of water after waking up in the morning and before going to bed. Then drink a glass of water before or after each meal, aiding digestion. 

Maintain a Healthy Weight

On top of making sure you have a healthy diet to boost your immunity, it’s also essential to maintain a healthy weight. Excess weight can affect how your body functions in numerous ways. 

Being considered obese (BMI of over 30) can be linked to lowered immunity response. It can also contribute to sleep problems, increased risk of some diseases, and lowered effectiveness of vaccines. 

Having Regular Checkups 

Be sure to schedule regular preventative checkups with your doctor. This can help catch any issues before they become a bigger problem. This can help keep your immune system functioning correctly by ensuring your health is in tip-top shape. 

It’s also essential to stay up to date on recommended vaccines like the flu shot, tetanus shots, and diphtheria shots. This gives your adaptive immune system a chance to develop a defense against these illnesses. This way, if you come into contact with it, you are less likely to get sick. 

Get More Rest 

Getting a total of 8 hours of sleep is vital to keep your body functioning correctly, including your immune system. This is because during sleep, your immune system releases proteins called cytokines. Cytokines are responsible for fighting off infections and inflammation.

The immune system’s interactions while we sleep help to reinforce its ability to “remember” how to recognize antigens. It also helps the immune system adapt to evolving antigens, like the flu virus. 

Exercise Regularly 

Physical activity has been known to help flush bacteria out of the lungs and airways. This helps to reduce your chance of getting a cold or flu.

The body’s brief rise in temperature during and right after exercise helps keep bacteria from growing. It will also help your body fight infections easier. 

Exercise also causes changes in your body’s antibodies and white blood cells. During exercise, antibodies circulate more rapidly, accelerating the immune system’s response to antigens. 

Regular exercise also helps to slow down the release of stress hormones. These hormones slow down the immune system’s response to antigens. 

Try high-intensity endurance training to get your immune system and the rest of your body in optimal health. 


One of the best ways to help keep your immune system healthy and keep antigens from entering your body in the first place is practicing good hygiene. There are a few things you can do daily to practice good hygiene. 

Washing your hands frequently is one of the best ways to stop the spread of germs. Be sure to wash your hands before and after eating, after working with chemicals, and after using the restroom. 

Cover your mouth and nose with your elbow rather than your hands when sneezing or coughing. This can help keep antigens from entering your body at all. 

When you get a cut or scrape, wash it with antibacterial soap and warm water. If the cut is severe, a doctor should examine it as soon as possible. Try not to pick at the wounds as they heal as well; this could allow antigens to enter your body through the bloodstream, 

Be sure to regularly wipe down any surfaces in your home that get touched regularly. This can include:

  • Door handles 
  • Counter Tops
  • Toilet seats and handles 
  • Sink Faucets
  • Refrigerator doors
  • Appliances

It’s also good practice to mop and sanitize your floors at least once weekly. If your home has areas with heavy foot traffic, you may need to mop more often. 

When cooking, rinses off all meat, poultry, and meats before cooking. Also, ensure you rinse any vegetables and fruits before eating them raw. Be sure to cook foods thoroughly to reduce the chances of getting any bacteria from undercooked foods. 

Reduce Your Stress Level 

When you experience high levels of stress, your body releases a hormone called cortisol. Cortisol reduces the number of lymphocytes in your blood, affecting everyday white blood cell communication. Which can make your immune system response time much lower than usual. 

Not to mention many stress-related illnesses are exceedingly hard to overcome. This is primarily because they are complex and multilayered with biological, psychological, and social factors. When this happens, our bodies continuously produce cortisol and other stress hormones, causing our immune system to be repressed. 

There are many ways to reduce your stress levels, including:

  • Meditation
  • Yoga
  • Keeping a journal
  • Unplugging from electronics
  • Read 
  • Get a creative hobby
  • Seek counseling

Changing Habits 

Some habits like smoking and consuming alcohol can lower your immune system’s response time. Steering clear of these can help boost your immune system and keep you healthy. 

Smoking can also increase the risk of immune system issues like rheumatoid arthritis. Rheumatoid arthritis is an autoimmune condition that causes your immune system to attack healthy cells. 

Alcohol can damage the epithelial cells, T-cells aka T lymphocyte cells, and other components of the gastrointestinal tract. This can alter the gut barrier function, allowing antigens to leak into circulation through your body. 

If you need help stopping these habits, talk to your doctor. They may be able to prescribe medications or recommend lifestyle changes that can help you quit. 

How to Tell if Your Immune System is Compromised

There are several ways to tell if your immune system has been repressed or compromised. These may not always be in ways that you would expect. 

For example, if you always have a cold. An average healthy adult typically catches a cold about 3 times per year. You should recover from these in about 7-10 days. 

But if you constantly catch colds that last for a prolonged amount of time, this is a good indication that your immune system isn’t as healthy as it should be. 

If you notice frequent diarrhea, gas, or constipation, you could also suffer from a lowered immune system. Boosting your immunity could help solve these kinds of issues. 

A lowered immune system can cause wounds to heal more slowly than average. You may also experience frequent infections from your slow-healing wounds. Your body may have issues trying to fight off these infections, which can cause further issues, be sure to see your doctor in this case.

There may be even more subtle signs that your immune system is suffering. Check out our questionnaire here to find out how at risk your immune system is. 

Stay Healthy

A healthy diet with plenty of fruits and vegetables, lots of water, and regular exercise is the best way to boost your immune system. As long as you keep your stress levels low and avoid unhealthy habits like smoking cigarettes and drinking alcohol, you should be able to keep a healthy immune system. 

We at Leo Costa Jr. are dedicated to helping you reach and maintain your health goals. Check out the rest of our blog and other resources for all your health and fitness concerns.