Coronavirus (COVID-19): What to Know & 10+ Foods That Could Naturally Boost Your Immune System

Reviewed by Dr. Richard Foxx, MD—Communities worldwide are being urged to stay indoors. Major events in politics, sports, and wider entertainment have been canceled or suspended. In March 2020, the entire country of Italy is on lockdown and regions across the globe are under states of emergency—all due to the spread of the novel coronavirus, or COVID-19. A global pandemic is here, and we’re likely yet to see the worst.

There are estimates that between 30% to 70% of North American populations could become infected with COVID-19. But what is this condition, how do you get it, and is there anything you can do build immunity and prevent contracting it yourself?

What Is a Coronavirus?

A coronavirus belongs to a family of viruses that can infect birds and mammals. In humans, it is known to affect the respiratory system, resulting in a range of conditions from the common cold and bronchitis to more severe iterations.

Severe Acute Respiratory Syndrome (SARS), which broke out in 2003 in 26 countries and affected more than 8,000 people, was a form of coronavirus. Another respiratory illness outbreak, Middle East Respiratory Syndrome (MERS-CoV), started in 2012 in Saudi Arabia and spread to the United States.

What Is COVID-19?

COVID-19 is a recently identified form of coronavirus. It was first identified in late 2019 in Wuhan, China. The virus and disease were unknown before the outbreak began. Although there is limited information on the new disease, it is evident that it spreads very easily and quickly between humans.

Information on the specifics of COVID-19 is still evolving. The first people identified to contract it had ties to animal and seafood markets, leading to the belief that it was originally transmitted from animals to humans. More recent diagnoses, however, indicate that humans can pass it to each other.

How Do You Get COVID-19?

You can get COVID-19 from people who have the virus. It can spread through small droplets from the nose or mouth that are expelled during coughs, sneezes, or exhales. If these droplets are inhaled by someone else, or fall onto a surface that someone else touches, they can get COVID-19.

For example, if you touch a surface that contains the virus and then your face, you can become infected.

In a brand-new study, published in the New England Journal of Medicine, researchers concluded the virus could last up to three days on stainless steel and plastic. It can last up to 24 hours on cardboard surfaces.

According to the new study, the virus can survive in air particles for up to three hours.

The World Health Organization (WHO) and U.S. Centers for Disease Control and Prevention (CDC) have made the following recommendations on how to prevent the spread of the virus:

• Avoid close contact with people (practice “social distancing,” which is leaving at least two meters, or six feet, of space between yourself and others).
• Wash hands often, particularly every time you arrive home if you need to go out. Do not touch your face when out in public.
• Limit the amount of time spent in public spaces.
• If soap and water are unavailable, use hand sanitizer that is at least 60% alcohol. Disinfect smartphones and other high-use items with alcohol wipes.
• Keep up to date with information about COVID-19 in your community.
• Stay home if you’re sick.
• Wear a face mask while indoors and outdoors when physical distancing is not possible. Always wear a mask if you’re sick.
• Clean and disinfect frequently touched surfaces in your home (if you are sick).

What Are the Symptoms of COVID-19?

Coronavirus symptoms vary between individuals and might be difficult to distinguish from a cold, flu, or allergies. Both the CDC and WHO report that symptoms often appear gradually, with the earliest signs appearing somewhere between two and 14 days after exposure.

Here is a table to help you discern whether you’re experiencing allergies, cold, flu, or COVID-19. Be aware that this list is not exhaustive and many symptoms overlap.

If you feel symptoms worsening, experience pressure or pain in the chest, or have trouble breathing, you should immediately report to a hospital or medical center for a COVID-19 test.

Who Is at Risk?

Although everyone is at risk for COVID-19, some groups are at higher risk for severe illness. Based on information out of China, people who are at increased risk include:

• Those with chronic medical conditions like cancer, heart disease, obesity, kidney disease, sickle cell disease, diabetes, lung disease (diseases that are associated with low-grade inflammation)
• Older adults

The WHO notes that most people who become infected (about 80%) recover from the disease without needing special treatment.

It is important to be aware of your coronavirus risk factors.

10-Plus Foods That Could Build Your Immune System Naturally

At this point, it appears as though individuals with weakened immune systems are the hardest hit by COVID-19. This does not, of course, mean that generally healthy people are in the clear.

Over the last week, we’ve seen announcements that professional athletes, who often follow regimented nutrition protocols, have high fitness levels, and are young, have been diagnosed with COVID-19. Only time will tell how they recover.

Although you can’t specifically tailor your immune system to fight COVID-19, you can do things that can help build overall immune strength. In most cases, this is true regardless of age or health status.

Many of the nutritional measures to boost immunity help by limiting inflammation and improving immune response; however, they do not work overnight. Here are some natural immune boosters for you to consider:

1. Bell Peppers

Tossed into salads, stuffed with cheese and rice, or layered in sandwiches, these colorful fruits are easy to incorporate into your diet. But the nightshades are also rich in vitamin C, a popular nutrient for cold and flu treatment.

Vitamin C can help boost immunity and limit the duration and severity of common colds. It is a powerful antioxidant that can promote cell health and limit inflammation, while being accessible in a wide variety of foods. You can also find it in kale, strawberries, and papaya.

Papaya, in particular, may have unique benefits for immune health because of its high vitamin C and probiotic content.

2. Garlic

This popular ingredient is also known for immune health. It contains a number of compounds that can provide immune support, with the most powerful being allicin. Allicin is converted into sulfur-containing compounds that, as research has shown, may boost the power and response of certain white blood cells.

Garlic has shown efficacy in both the treatment and prevention of colds and flu.

Chopping and crushing garlic is the best way to activate allicin. So, after chopping, keep your garlic away from heat for 10 minutes before cooking.

3. Ginger

Ginger is another nutrient-dense plant that’s known to have significant benefits to fight infection and boost immune strength. One lab study found that ginger could stimulate the immune system to kill viruses. Ginger is also noted to possess anti-inflammatory properties, which can also help support a healthy immune system.

Treat yourself to a cup of soothing ginger tea by boiling a two-inch piece of gingerroot (peeled and thinly sliced) in two cups of water. Add some raw honey and lime juice to taste.

4. Plain Yogurt

Foods featuring probiotics, like yogurt, may offer immune support. A healthy population of gut microbes is associated with lower levels of systemic inflammation and improved immune function.

Your healthiest option is plain Greek yogurt, as flavored varieties are often loaded with sugar. You can add your own flavor by drizzling with raw honey and/or sprinkling berries and nuts on top.

5. Almonds & Peanuts

Foods rich in fat-soluble vitamin E, like almonds and peanuts, are essential to immune health. Vitamin E is a potent antioxidant that helps protect cells from the harmful effects of free radicals. It is available in a wide variety of foods, which is the best place to get vitamin E. Supplementing, especially at large doses, can be harmful.

6. Green Tea

Green tea is a terrific source of antioxidants and amino acids that can boost immune strength. First, it the best source of epigallocatechin gallate (EGCG), a powerful antioxidant that has been shown to boost immune response to fight infections. Green tea is also a good source of L-theanine, which can enhance immune function by stimulating the secretion of immune-cytokines (early responders to infection).

Other sources of L-theanine include coffee, black tea, and oolong tea.

7. Turkey

Turkey, like other meats, is a good source of vitamin B₆. Research has shown that vitamin B₆ increases immune response in critically ill patients, and is a known role player in a healthy immune system.

Other sources include cold water fish, whole grains, eggs, leafy greens, and beans.

8. Oysters

More than just an aphrodisiac, these saltwater mollusks are one of the best food sources of zinc. Zinc is a trace mineral associated with strong immune function. It plays a role in both developing immune cells and immune cell function. There is also some evidence that adequate zinc intake can reduce the risk of infection from a host of pathogens.

Zinc deficiency is very rare. In addition to oysters, you can get it from whole grains, milk products, red meat, poultry, beans, and nuts.

9. Shiitake Mushrooms

Evidence suggests that shiitake mushrooms, the brown-capped fungi popular in Asian cuisine, can offer benefits to immune health. Long used for medicinal purposes, one study showed that eating two dried shiitake mushrooms per day could reduce inflammation and improve the number of immune markers in the blood.

Shiitake mushrooms have also been found to promote heart health.

10. Elderberry/Elderflower

Elderberry is a herbal supplement that may help fight cold and flu infections. Studies have shown that elderberry extracts/syrup can significantly reduce the duration of flu-like symptoms. It’s possible these effects are due to high concentrations of antioxidants that boost immune response.

COVID-19 Prevention and Treatment: Stay up to Date

According to many sources, the COVID-19 outbreak in North America will likely worsen before it improves. China recently announced the virus peaked roughly eight weeks following its discovery and reported cases are decreasing. Using that as a guideline, we can likely expect to be living with the threat and reality of COVID-19 for the coming months.

Do your best to stay up to date with new information from the WHO, CDC, and local news outlets. There is currently no cure or vaccine for COVID-19. While taking steps to reduce your risk and enhance your immune system is worthwhile, it is no guarantee against infection.