Each fall and winter, you likely start hearing lots of claims about “boosting” your immune system, especially in relation to cold and flu season. But we know you’re after the facts, and some claims made by so-called miracle drugs may not be all they’re cracked up to be. And as the COVID-19 pandemic continues, it’s important to separate fact from fiction.
While you probably aren’t interested in earning an advanced degree in immunology (like our friend Dr. Steve Kleiboeker), you deserve to know how your body is working to keep you healthy - and what you can do to help it function well and protect you from illnesses like colds, the flu, and COVID-19.
How does my immune system work?
The immune system is a complex system designed to protect your body from invaders such as bacteria, viruses, toxins, or other threats to our overall health. Your immune system is divided into two categories: the innate immune system and the adaptive immune system.
The innate immune system is the system that we’re born with. This system recognizes viruses, toxins, bacteria, or other foreign invaders that don’t belong in our body. When something is detected inside of our bodies, our innate immune system launches cells that fight back, protect our bodies, and repair damage that may have occurred. Innate immune responses are quick, but don’t provide a response that’s specific to a particular germ or virus.
If the innate immune system isn’t able to be the first round of defense, the adaptive immune system helps provide a second, more specific response, and can help you build immunity against future attacks. Your adaptive immune system is made up of T-cells, B-cells, and antibodies, but often responds more slowly than the innate immune system.
Can I boost my immune system?
So is it even possible to “boost” your immune system’s function? Well, not exactly. Immune health is influenced by many factors, including your age, weight, gender, previous illnesses, stress, and genetics, as well as sleep, diet, and exercise. While some of those factors are in your control, many of them aren’t.
One 2015 study of 210 healthy twins between the ages of 8 and 82 found that most traits that determine our immune system function aren’t inherited traits. As the twins were observed, the study found that immune systems vary as we age and as we get exposed to different microbes in our environment. That means no two systems are alike - and there’s no one way that’s guaranteed to “boost” it.
Additionally, it is possible to have an immune system that’s too high functioning, which can lead to autoimmune diseases. Autoimmune conditions (like type 1 diabetes, Hashimoto’s thyroiditis, or inflammatory bowel disease, to name a few) are a broad range of illnesses where your immune system mistakenly attacks healthy cells in your body, which can cause serious health problems.
However, these autoimmune conditions often have complex causes, and likely won’t be caused by practicing good health habits like getting enough sleep, eating a balanced diet, and getting moderate exercise.
How can I help my immune function?
Even though there isn't a single magic bullet that gets your immune system firing on all cylinders, you can still take action to help your overall immune function during cold and flu season. And if you have any cold or flu symptoms, be sure to rule out a possible case of COVID-19 with an at-home COVID-19 test.
- Eat a diet rich in fruits, vegetables, and Asian mushrooms.
- Make sure you have optimal levels of Vitamin D and other nutrients.
- Get 7 to 9 hours of sleep per night.
- Monitor and decrease your inflammation levels.
- Get enough omega-3 fatty acids in your diet.
- Don’t smoke.
- Get 30 to 60 minutes of moderate exercise per day to improve immune function.
- Supplement your diet with vitamin D, vitamin C, and zinc (but we recommend checking with your healthcare provider first).
Your immune system is a powerful defense against all kinds of invaders - so take action and help it do its job!
 Brodin, Petter, et al. “Variation in the Human Immune System Is Largely Driven by Non-Heritable Influences.” Cell, vol. 160, no. 1-2, 15 Jan. 2015, pp. 37–47., doi:10.1016/j.cell.2014.12.020.
 Nieman, David C. “Coronavirus Disease-2019: A Tocsin to Our Aging, Unfit, Corpulent, and Immunodeficient Society.” Journal of Sport and Health Science, vol. 9, no. 4, July 2020, pp. 293–301., doi:10.1016/j.jshs.2020.05.001.