Your immune system consists of a complex collection of cells, processes, and chemicals that constantly defends your body against invading pathogens, including viruses, toxins, and bacteria.

Keeping your immune system healthy year round is key to preventing infection and disease. Making healthy lifestyle choices by consuming nutritious foods and getting enough sleep and exercise are the most important ways to bolster your immune system.

In addition, research has shown that supplementing with certain vitamins, minerals, herbs, and other substances can improve immune response and potentially protect against illness.

However, it’s important to note that no supplement will cure or prevent disease.

With the 2019 coronavirus COVID-19 pandemic, it’s especially important to understand that no supplement, diet, or other lifestyle modification other than social distancing and proper hygiene practices can protect you from COVID-19.

Currently, no research supports the use of any supplement to protect against COVID-19 specifically.

Instead, this article provides information on well-researched supplements that may bolster immune system defenses in general.

Note that there are many types of coronaviruses, some of which, like the common cold, cause only minor symptoms unlike COVID-19, which often results in serious, sometimes fatal symptoms.

Vitamin D
Vitamin D is a fat soluble nutrient essential to the health and functioning of your immune system.

Vitamin D enhances the pathogen fighting effects of monocytes and macrophages white blood cells that are important parts of your immune defense and decreases inflammation, which helps promote immune response.

Many people are deficient in this important vitamin, which may negatively affect immune function. In fact, low vitamin D levels are associated with an increased risk of upper respiratory tract infections, including influenza and allergic asthma.

Some studies show that supplementing with vitamin D may improve immune response. In fact, recent research suggests that taking this vitamin may protect against respiratory tract infections.

In a 2019 review of randomized control studies in 11,321 people, supplementing with vitamin D significantly decreased the risk of respiratory infections in people deficient in this vitamin and lowered infection risk in those with adequate vitamin D levels .

This suggests an overall protective effect.

Other studies note that vitamin D supplements may improve response to antiviral treatments in people with certain infections, including hepatitis C and HIV.

Depending on blood levels, anywhere between 1,000 and 4,000 IU of supplemental vitamin D per day is sufficient for most people, though those with more serious deficiencies often require much higher doses.

Vitamin D is essential for immune function. Healthy levels of this vitamin may help lower your risk of respiratory infections.