Why Quercetin Belongs in Your Immune Support Kit

Why Quercetin Belongs in Your Immune Support Kit
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Are you ready to boost your immunity and be better prepared to face any possible assaults from bacteria, viruses, and fungi? We all need to be ready to help keep our immune system operating at its very best, and that means doing a variety of things, such as following a nutritious diet, getting adequate sleep, avoiding environmental toxins, staying hydrated, and practicing stress management, among other things. Among those “other things” is the use of herbal remedies that have been shown to work with the immune system.

Immune System Basics

The immune system consists of a wide variety of players, including antibodies, white blood cells, bone marrow, lymph nodes and vessels, thymus, the complement system (composed of various proteins that complement the antibodies), and spleen. Its job is critical: to protect the body against harm from bacteria, fungi, physical trauma, viruses, stress, toxins from the environment and food, and other bad guys.

Your immune system is activated by substances that your body doesn’t recognize as friendly or as its own. These substances are called antigens, and when they attach to receptors on the immune cells, different processes can occur and result in some type of response, such as symptoms of the cold or flu, inflammation, cell mutations, or other reactions.

The immune system has two subsystems, called the innate and adaptive immune systems. Both of them work together to deal with invasive substances, but they also work in different ways. The innate system offers a general defense against invasive substances and fights those that enter the body through the digestive system or the skin.

The adaptive immune system produces antibodies that it uses to fight certain germs that it has encountered before. For example, if you’ve had the measles and recovered, your adaptive system will recognize and fight off any future exposures to the measles.

Naturally, the best way to support the immune system is to avoid all of the factors that can bring it down. In real life, however, that isn’t possible, which is why we often bring in helpers, including herbal and nutritional remedies. One of those remedies is called quercetin.

Quercetin is found in berries, citrus fruits, grapes, and more. (pilipphoto/Shutterstock)
Quercetin is found in berries, citrus fruits, grapes, and more. (pilipphoto/Shutterstock)

What Is Quercetin?

Quercetin is a pigment that is a member of a group of plant compounds called flavonoids. It’s found in a variety of vegetables, fruits, and grains, but it’s also available in supplement form. Quercetin is a potent antioxidant, and a number of research studies have indicated it may help reduce inflammation, which is the root of most diseases. 

What’s Special About Quercetin?

People take quercetin supplements for a variety of reasons, including a desire to enhance their immunity and reduce inflammation, which in turn can affect a number of health concerns and symptoms. Some of the benefits that have been attributed to quercetin include the following:

  • Reduce Inflammation

High levels of free radicals, which are molecules that can cause disease and other health challenges, may result in inflammation. Both animal and human studies have indicated that the use of quercetin may help reduce inflammation. In one study, for example, women with rheumatoid arthritis responded well to 500 mg of quercetin with improvements in morning pain, early morning stiffness, and pain after exercise.

  • Help Enhance Immunity

Quercetin has properties that may reduce the risk of infection. It also has “a direct regulatory effect on basic functional properties of immune cells,” according to a study in Biocell. This flavonoid plays an important role in regulating the immune system’s response to stressors through several types of proteins called kinases and phosphatases that are necessary for cells to function optimally. Therefore, this flavonoid may have a significant impact on overall health.

  • Suppress Histamine

Do you experience annoying allergy symptoms such as a stuffy nose, sneezing, nasal drip, and scratchy throat? Results of animal studies show that quercetin may suppress histamine and block enzymes involved in inflammation. More research is needed to determine the potential impact on humans.

Where to Get Quercetin

Among the foods that provide quercetin are green and yellow bell peppers, onions, shallots, asparagus, cherries, tomatoes, red apples, red grapes, kale, red leaf lettuce, berries, and green and black teas. The skin or outer peel provides the greatest amount of this flavonoid.

Quercetin is also available as a supplement in capsules and powders, sold as a single-ingredient or in formulations that include other nutrients. Some people have difficulties metabolizing quercetin on its own; by adding bromelain or Vitamin C to a formula, absorption can be increased. A typical dose of quercetin is 250 to 1,000 mg daily.

Bottom Line

Maintaining a healthy immune system is important for everyone, and fortunately, there’s more than one way to do it through wise lifestyle choices. Use of natural supplements such as quercetin as well as probiotics, specific vitamins and minerals like Vitamin D, medicinal mushrooms, and enzymes can complement those choices.

This article was originally published on NaturallySavvy.com


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Andrea Donsky, who holds a bachelor of commerce, is an international TV health expert, best selling author, and founder of NaturallySavvy.com—a recipient of Healthline’s Best Healthy Living Blogs for 2019. This article was originally published on NaturallySavvy.com