The immune system is the body’s defense against infections. Recently, we’ve heard a lot about immunity and how it’s important in protecting against viruses like COVID-19. We’ve also heard a lot about how older people and those who are immunocompromised are at a higher risk.

What parts of the body relate to the immune system? Can you really “boost” it? If so, with what exactly?

These are likely questions you’ve received from friends, family, and clients, so we’ve put together an easy to understand guide so you can be sure you’re providing smart and sensible advice.

What part of the body is the immune system located?

Let’s begin with the basics. Most cells and organs in the body work together to offer protection against bacteria, pathogens, and viruses. Your white blood cells – just one component of your blood – act as your body’s defense army.

There are a few different types of white blood cells, all with specialized roles. Some are responsible for engulfing and destroying unwanted organisms, whereas others work to create a memory bank of invaders so they can be more prepared next time.

You have blood throughout your entire body, but up to 70% of your white blood cells are found in your gut. This shouldn’t be surprising since Hippocrates, the father of medicine, said, “All disease begins in the gut.”

How does the immune system work?

When the body senses foreign substances – often referred to as antigens – the immune system works to recognize these invaders and get rid of them as quickly as possible. The white blood cells, whose primary function is memory, create antibodies that lock onto antigens, so if you encounter that particular invader again (often referred to as a strain) you might not get as sick. This is why someone who has had a disease like chickenpox, for example, is less likely to get it again.

Antibodies are also how vaccines and immunizations work. An immunization introduces the body to an antigen in a way that doesn’t make someone sick, usually in a small dose. This allows the body to make antibodies that will offer defense from a future attack by the invader. In collaboration with other types of white blood cells that work to neutralize and kill the invaders, antibodies play an important role in the defense system of the body. Collectively, this protection is called immunity.

I’ve heard a lot about different types of immunity. Why is there more than one type?

Humans have three types of immunity — innate, adaptive, and passive. Everyone is born with innate (or natural) immunity, a baseline general protection. For example, the skin acting as a barrier to block germs from entering the body is an example of innate immunity.

Adaptive immunity builds up over time, which is why a 10-year-old has a more robust immune system than that of a newborn baby. Adaptive immunity can come from general exposure to toxins and diseases or from vaccines and immunizations.

Passive immunity is “borrowed” from another source and has a limited lifespan. As an example, antibodies in a mother’s breast milk provide a newborn baby with temporary immunity to diseases the mother has been exposed to.

Herd immunity is a type of immunity management. Herd immunity occurs when enough people become immune to a disease that it slows or stops the spreading. Herd immunity is not yet recommended as a way to control COVID-19 since so much about the disease is unclear.

I want to make my immune system strong. What can I do?

While there is no cure or clear treatment for COVID-19 at this time, there are many things you can do to strengthen and bolster your immune system. There is a lot of conflicting information online right now, so it’s important to get clear on the dos and don’ts of immune building.

The primary immunocompromised conditions that make people more susceptible to a more severe COVID-19 infection include diabetes, hypertension, and COPD. While there are many different ways to develop these conditions, obesity is a primary risk factor. Eating a healthy diet and maintaining a controlled weight will reduce your risk of developing chronic health conditions like this and in turn, reduce your risk of developing complications with dangerous viruses like COVID-19.

When we choose unhealthy foods with little to no nutritional value our body has to process these as toxins. Think of it as using up valuable resources of white blood cells! Eating a diet rich in antioxidants, however, will help increase your white blood cell count and ensure your body has the tools it needs for maintaining a stellar defense.

For those with autoimmune conditions, history of certain cancers like leukemia, as well as underlying infections that keep white blood cells low, it’s even more important to eat a diet rich in fruits, vegetables, healthy proteins, while limiting sugar, processed fats, and any other foods that you know to be inflammatory to your body.

While there is no quick fix or cure for the current coronavirus, there are many things you can do to support your immune system and give your body the best protection at a time when it needs it most. Sleep and reducing stress also play an important role in immune response. It’s difficult right now, but try and settle into a routine knowing that some things cannot be controlled while other things can, like the food you choose to nourish your body and the mindset you can adopt.

How are you staying healthy right now?