Over the last few years, we've all probably thought about our immune systems more than ever before. Complex and fascinating, our immune system keeps us safe from pathogens, bacteria, viruses, and germs that we encounter in our daily lives. We rely on our bodies to keep us resilient even while we move throughout the world.
But what can you do, practically speaking, to maintain your immune system? What are the signs that indicate a well-functioning or a poorly-functioning immune response?
These are the questions this article seeks to answer. By the end, you’ll be familiar with your immune system and know what you can do to support and nourish your immune system for better health. Let’s get started.
What Is the Immune System?
Before we get into the weeds, let’s first break down what exactly your immune system is. That way, we can better understand how to target it with proper support.
The immune system is made up of specific cells, proteins, and organs in the body which work in synergy to keep you safe from infections, viruses, and parasites. Some elements of the immune system focus on getting invaders out of the body as soon as possible (think of your sneeze reflex, or a strong reaction to bad food), while some specialized cells send signals to mobilize a more robust immune response.
What Are Its Various Parts?
The immune system is made up of two equally-important halves: the innate (general) immune system, and the adaptive (acquired, specialized) immune system.
The innate immune system is what we have from birth: the general, non-specific responses that any well-functioning human body possesses. Get a papercut? Your innate immune system causes minor, temporary swelling (inflammation) at the site to stop blood loss and to stop any harmful bacteria from circulating throughout the body.
Major components of the innate immune system are the skin and mucous membranes, stomach acid and enzymes (to destroy pathogens that enter the body through the mouth), and special circulating cells (including NK cells) which roam throughout the blood stream, looking out for invaders. The innate immune system reacts quickly — often within just a few hours — but is less "intelligent" or targeted in its response.
By contrast, the adaptive immune system learns over time from every cold, virus, and pathogen we've encountered in our lives. While it reacts less quickly than the innate immune system, it can respond with an entire dossier of the weaknesses of this particular invader, leading to a much more targeted and strategic immune response. The stars of the adaptive immune system are T cells, B cells, and the antibodies.
Our skin, mucus membranes like our noses and mouths, and balanced gut microbiome are critically important to proper immune response.
What Does an Unhealthy Immune System Look Like?
If your immune system is not as healthy as it should be, your body won’t be able to function optimally. You come into contact with pathogens every day, and your immune system is constantly fighting them off, so it needs to be in top form.
Here are some signs that your immune system might not be fully supported.
High Stress Levels
Large amounts of stress aren’t the result of a weak immune system, but they can be a cause of it. When your body is stressed, it releases a hormone called cortisol. Cortisol starts to signal the fight-or-flight response in your body, and it causes resources to be diverted to high-priority areas in a life or death situation, like the heart, muscles, and lungs.
This is great for a dangerous scenario, but if cortisol stays in the body for too long, it can weaken other parts of the body, such as the digestive system and immune system.
Because of this, it’s always important to keep your stress in check and keep your various systems operating at the levels they should.
If you are constantly getting sick or having the same cold for several days or even weeks, it is likely a sign that your immune system needs some support.
Most people get between two and three colds per year. They’re a perfectly normal part of life, and they tend to go away in about a week. It takes your immune system three or four days to form an immune response and another few days to carry it out.
But if you’re getting more colds than this each year, or if your colds last longer than normal, you might want to bolster your immune strength.
Problems With Your Gut
It’s estimated that about 70% of your immune system exists within your gut. Countless beneficial bacteria live in your gut, fighting infection and supporting the immune system.
If your gut bacteria are unhealthy, it could compromise your immune system. Signs of an unhealthy gut microbiome are frequent diarrhea, gas, or constipation. If you experience these symptoms regularly, you may need to check in with your immune system.
What Does a Healthy Immune System Look Like?
If your immune system is properly supported, your body can protect you from infection as it should. This can have numerous positive effects on your body, saving you a lot of time and energy. Here are some signs that your immune system is working well.
No matter how perfectly you eat or how diligently you take your supplements, you'll still come down with something from time to time...but a well-functioning immune system will have you bouncing back well from these normal, everyday colds.
Healthy Digestive System
With 70% of the immune system being in your gut, it’s likely that if you have a healthy digestive system, your immune system is also fairly healthy. If you have regular, healthy bowel movements and don’t experience bad gas or constipation, that can be a good sign that your immune system is healthy.
Feeling Well-Rested and Energetic
If your immune system is working overtime trying to fight infection, it will consume a lot of energy. If you’re feeling tired all the time, even after a good night of sleep, your body might be fighting off an infection without you realizing it. It’s also possible that your immune system is unhealthy if you have this problem.
But if you are getting good sleep and that sleep is restful and rejuvenating, that can be a good sign that your immune system is working well.
How Can I Maintain My Immune System?
Now that we know what a healthy immune system looks like, let’s talk about what you can do to support your immune system so that it can work well for you.
A healthy diet is a great first step to a healthy immune system. Eating large amounts of processed foods can take a toll on your digestive system and thus your immune system.
So it’s best to avoid unhealthy fats like trans fats, avoid large amounts of sugar, and keep your alcohol intake to one or two drinks per day. In addition, it’s important to feed your gut microbiome with large amounts of fiber to keep it healthy and active.
This all works to keep your digestive system healthy and working properly.
Making sure to get proper sleep each night is another important step to take to support the health of your immune system. Sleep is a time for your body to recuperate and get rid of any waste that gathers throughout the day.
Sleep is an important regulator for the immune system, especially the lymphatic system. So make sure to get seven to nine hours of sleep every night, and try to go to sleep and wake up at the same time every day. This will help your body get into a healthy rhythm.
The right nutrients are critical for a healthy immune system. Vitamin C and other antioxidants are important vitamins that your immune system utilizes, fighting free radicals and keeping the cells healthy.
But another incredibly important nutrient is omega-3, specifically EPA (eicosapentaenoic acid). EPA helps to support a healthy inflammatory response in the gut, which, as we’ve discussed, is an important part of the immune system.
Omega-3 can help keep your gut healthy and keep inflammation moderated so that your microbiome can be as healthy as possible. It’s an amazing way to support the largest part of your immune system.
On top of that, omega-3 fatty acids play a key role in the function of several specialized immune cells, so finding a consistent source of omega-3s to add to your daily routine will go a long way towards nourishing your immune system.
Support Your Immune System
Now that you've learned more about how your immune system works, what signs you might see if it is underperforming, and the steps you can take to support it, we hope you feel more empowered to take charge of your health. Remember, three key components to a resilient immune system are a healthy diet low in sugar and high in nutrients, 7-9 hours of quality sleep, and great gut health, supported by omega-3s.
6 Signs You Have a Weakened Immune System | Penn Medicine
Immune system explained | Better Health Channel
To boost immunity, look to the gut | Vital Signs | UCLA Health