top of page
  • Writer's pictureAlan Frischer, MD, MPH

Immune System

Throughout this pandemic, I’m frequently asked about taking various supplements to build up the immune system. Do the many products out there have research and science to support their claims? Can they help us to prevent or minimize the threat from COVID-19?

Why do some of us get sick when exposed to a pathogen, while others do not? The answer revolves around a number of variables, including nutrition, sleep, exercise, hygiene, age, and genetics; as well as the absence of recreational drugs, cigarettes, alcohol, stress, and underlying illnesses. Rather than making major changes to our entire lifestyle, many of us look for an easy answer - like taking zinc or vitamin C. But, in the absence of making real changes to the other variables, can supplements help?

A number of herbs and supplements have been examined over the past several years, including vitamin D, zinc, vitamin C, elderberry, medical mushrooms, garlic, licorice, and vitamin B complex. These have found some limited level of support from varying levels of scientific research. (Others have found no scientific support at all.) Unfortunately, taking them has not been proven to add a significant boost to the immune system. Having said this, a review of 25 studies published in the British Medical Journal did find that a moderate dose of vitamin D offered some protection for those whose vitamin D levels are already low. Vitamin D levels are measured by a simple blood test.

Our immune system attempts to achieve a balance between limiting the ability of bacteria, viruses, and parasites that cause infection, while not becoming hyperactive and leading to allergies, diabetes, and other types of auto-inflammatory and autoimmune disorders. If there were indeed a supplement that could supercharge our immune system, it would also need to not swing too far and trigger negative effects.

So what is the best way to boost our immune system? Stop me if you have already heard this. Seriously: You may stop reading here. I’ve said it before:

  • Stay active. The key to exercise is to use moderation. As with many things, there's a sweet spot - too much exercise can also put too much stress on the body, which will depress the immune system. And, doing too much will likely motivate you to stop exercising. For many, the sweet spot may be 30 to 60 minutes of exercise, four days each week.

  • Work on your diet. The gut (intestines) makes up a significant part of our immune system. When it is healthy, so is the immune system. Emphasize vegetables, fruits, whole grains; fermented foods like yogurt; and healthy fats and protein like fish, beans and nuts. Limit meat, fried foods, processed foods, and simple carbs.

  • Manage stress. A strong link exists between mental health and the immune system. Chronic stress suppresses the immune system. It is not possible to avoid stress in our lives, but it is possible to adapt strategies to help better manage it.

  • Get enough sleep. Lack of sleep causes the body to produce stress hormones like cortisol. These hormones keep us awake and alert, but can suppress the immune system. Those who get enough sleep have higher levels of T cells, which help to fight infection.

I’d love to be able to recommend a magic pill in the form of an herb or vitamin. However, the very best way to maintain a strong immune system and to prevent colds, flus, and other viruses appears to be through a healthy lifestyle. I encourage you to focus on these basic principles during this crisis, and to maintain these practices into the future as we emerge beyond it.

1 view0 comments

Recent Posts

See All


bottom of page