Support Your Immune System Against Coronavirus, Cold and Flu

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With novel coronavirus (COVID-19) taking the world by storm, life as we knew it has transformed dramatically over the last several weeks.

The most important thing to do in the face of a pandemic like this is to not panic. Stressing out about possibly contracting this illness can weaken your immune system and leave you more vulnerable to it. Instead, make rational, smart decisions, and bolster your immune system naturally, so if you happen to be exposed to the coronavirus, you’ll be better able to fight it.

Coronavirus Symptoms and Testing

COVID-19 is a zoogenic virus, which means it can be transmitted between humans and animals (such as birds and cats). It is part of a family of seven coronaviruses known to affect humans. Some (229E, NL63, OC43, and HKU1) cause mild-to-moderate common cold symptoms, while others like SARS (Severe Acute Respiratory Syndrome) and MERS (Middle East Respiratory Syndrome) can result in more serious symptoms. As it has been newly identified, COVID-19 is referred to as a “novel coronavirus” and, like SARS, its symptoms can be more severe.

According to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), common COVID-19 symptoms include fever, shortness of breath, a dry cough, and tiredness. Less common symptoms include aches and pains, runny nose, congestion, sore throat, and diarrhea. Symptoms have “ranged from mild to severe” in afflicted individuals, even leading to death in those who developed complications like pneumonia.

The organizations also state that, while the risk factors for severe coronavirus symptoms aren’t yet clear, older adults and people with chronic medical conditions like high blood pressure, diabetes, and heart disease are at higher risk. Still, a few relatively healthy younger people have also experienced severe symptoms or died, highlighting the need for vigilant protective measures.

Considering that novel coronavirus symptoms could also be due to a common cold or flu, it’s tough to determine whether a person actually has this illness, or if the symptoms are due to something else. Over the last several weeks (after the CDC expanded the federal criteria to test for COVID-19 and the FDA recently enabled more labs to start producing their own test kits) tests have become more widely available, and independent labs should be producing them on a mass scale soon.

Unless everyone is tested, though, there’s no way of knowing who actually has the novel coronavirus. Iceland (with the help of deCODE Genetics, a biopharma company) recently tested 3.2% of its population (symptoms or no symptoms) and found that many of those who tested positive were asymptomatic. As more people get tested in the U.S., authorities will have a better grasp of how COVID-19 spreads.

Coronavirus Transmission

The CDC states “symptoms may appear 2 to 14 days after exposure,” but also explains this statement is based on previous observations of the incubation period of MERS-CoV, a different coronavirus. The CDC’s discussion on how COVID-19 spreads is also “largely based on what is known about similar coronaviruses.”

Hence, the CDC says this novel coronavirus likely spreads from person-to-person–those in close contact (within approximately 6 feet) with an infected person, and through respiratory droplets when an infected person sneezes or coughs. While touching surfaces with infected respiratory droplets and then touching your nose or mouth could transmit the virus, the CDC believes it’s not the main way the virus is spread.

To help prevent the spread of COVID-19, many Americans are virtually homebound and practicing what has become the buzz-phrase of the 21st century, “social distancing.” Economic and social implications aside, social distancing seems to be the best temporary measure for protecting the mass population in the absence of universal testing.

That said, social distancing will certainly have an impact on our psycho-emotional well-being (and for some, on their physical safety). I am especially worried about people who live alone. Now may be the perfect time to adopt a dog or cat for loving companionship. Having vital connections in our lives helps keep us healthy.

I personally have been Skyping more than ever now with family, especially my grandchildren that were supposed to come visit us this month. Reaching out regularly to family and friends by phone or computer is one way to nurture those vital connections.

Having hope and keeping your spirits up is crucial during times like these. Do things that bring you joy, be grateful for what you have now, and focus on the positives. This could mean more time with family, getting things done around the house you never had time for before, or learning new skills or hobbies.

How to Support Your Immune System

Your immune system is not found in one single place in your body, like your brain or heart. This defense system is a complex, diffuse, and integrated intelligence network of organs (like your skin and liver), tissues (mucous membranes are an example), cells (such as white blood cells), cellular products like antibodies—and at the subatomic level, electrons.

They all work together, an army of specialized units, in wondrous around-the-clock synchrony designed to protect you against pathogens, toxins, poor lifestyle choices, and stress. Here are my top tips to support your immune system, keeping it primed and ready to tackle viral threats.

Get Adequate Rest

You’ve heard it before and you’ll hear it from me repeatedly because it’s so basic. Too much activity and not enough rest is a ticket for trouble, and in this case, weakened resistance. Many studies show that not enough sleep suppresses the immune system and undermines your ability to fend off microbial infections. I recall a 2009 study in which poor or shorter sleep in the weeks preceding exposure to a rhinovirus (the most common viral infective agent and the cause of the common cold) were associated with lower resistance to illness. 

Minimize Your Stress

Worry, anxiety, anger, depression, or any emotional conflict effectively drain the immune system and leaves you more vulnerable. A major 2012 study found that people with chronic stress are more likely to develop persistent cold symptoms than stress-free individuals. Chronic stress overproduces the stress hormone cortisol, which then fails to appropriately regulate inflammatory responses in the body. An inflammatory response lingers long after the cold virus is gone, creating continuing symptoms. We all have stress in our lives. We just need to find ways to defuse it.

Be Mr. or Ms. Clean

Wash your hands with soap regularly and often. Pathogens are everywhere, and in a day’s activities, we constantly touch many. Without realizing it, we touch our nose, mouth, and eyes. According to the CDC, hand washing is an important measure to prevent getting sick and spreading germs. Doing so reduces respiratory illnesses, like colds, in the general population by 21%.

Whenever I used to see patients who were sniffling, sneezing, coughing, or rubbing itchy eyes, I made it a point after each visit to wash my hands before seeing my next patient. I didn’t want to be a middleman transferring germs from one person to the next or upping my own risk of infection. Part of my daily routine today is filling my bathroom sink with warm water and adding a half teaspoon of sea salt. I immerse my face, blink my eyes, and gently sniff the water into my nostrils. This simple facial dip helps zap microorganisms present in these common entrances to the body.

Eat a Nourishing, Anti-Inflammatory Diet

As part of my heart health strategy, I have always recommended the Pan-Asian-Modified-Mediterranean (PAMM) diet, which includes seaweed, a source of more than 50 minerals. Seaweed contains a higher concentration of magnesium, iron, iodine, and sodium than any other kind of food.

The diet contains the right kinds of carbohydrates, proteins, and fats, with plenty of fruits and vegetables, olive oil and garlic, to benefit your immune system as well. Eat homemade chicken soup frequently, particularly if you come down with signs of a cold. It is a great immune booster, and even more so when reinforced with ample garlic, a natural antibiotic and antiviral remedy that has been used worldwide for centuries. Don’t forget to include fresh herbs like rosemary and thyme in your meals – some of the most powerful immune boosters are right in your garden!

It’s also very important to avoid sugar and junk food. Sugar inhibits phagocytosis, a process in which viruses and bacteria are destroyed by white blood cells. I would also minimize, if not eliminate, your alcohol and caffeine consumption.

Get Grounded

Grounding, also known as Earthing, is reconnecting with the natural and gentle electric charge on the surface of the Earth. This can easily be done by going outside barefoot, or by having bare skin contact with grounded and conductive sheets, mats, bands, or patches while you sleep, relax, or work indoors. Although there are no studies yet to show a link to fewer infections, Earthing can reduce inflammation, help defuse stress and normalize the stress hormone cortisol, as well as improve blood flow throughout the body.

As it attunes the body to the Earth’s natural electromagnetic frequency, Earthing can counteract the negative effects of man-made EMF from wireless devices like Wi-Fi routers, cell phones, and cell towers. With the rollout of 5G in cities across the U.S. and the resulting exposure to unprecedented levels of electromagnetic radiation, now’s a particularly important time to ground. I firmly believe Earthing benefits contribute to a stronger immune system.

On a related note, my scientific colleagues and I continuously discuss the probable harmful health effects of 5G technology, and I believe 5G will probably have a negative impact on the immune system. Many researchers have said that non-thermal radiation from wireless devices is thought to cause a cellular stress response, which can ultimately tax the immune system. Not to mention, 5G has not been tested for long-term safety or health effects (which explains why 5G proponents are so quick to assert that there’s “no evidence” demonstrating 5G as a health threat). As a precautionary measure during times of illness, try to distance yourself from wireless electromagnetic devices and areas where 5G has been implemented.

Soak Up Some Sunshine (or Supplement with Vitamin D)

Your bare skin has the natural ability to convert sunlight into vitamin D, a critical hormone-like substance that, among many other benefits, exerts a fundamental role in maintaining immune system effectiveness and protection against upper respiratory infections, including the common cold, flu, and pneumonia.

Fall and winter, however, mean less available sunlight, particularly in the northeast where I live. But many people, even if they live in the Sunbelt, don’t get out into the sunshine enough. So, no matter where you live, make an effort to get out in the midday sun (10 AM to 2 PM) for 20 minutes or so to stoke your vitamin D supply, and as “insurance” supplement with 2,000 to 5,000 IU of vitamin D3 daily. Experts increasingly regard vitamin D as “a new anti-infective agent” that can impact a broad array of pathogens, and, as I have already reported, helps reduce infections and antibiotic use, even among the more susceptible elderly population.

Take Targeted Nutritional Supplements

In addition to vitamin D3, many potent nutritional supplements can power up your immune system and help keep it running optimally. Here’s a rundown on some of my favorites:

  • Multivitamin and mineral–Everyone stands to benefit from a high-quality formula loaded with basic vitamins and minerals, some of which may be in short supply in a typical Western diet.
  • Garlic–As an Italian, I have great respect, not just for the flavor boost of garlic in food but also for the powerful boost it provides to the immune system. As a supplement, look for high allicin content. Allicin is the potent sulfur compound in garlic with the knockout punch. I recommend 1,000 mg a day of garlic. You may develop a garlic breath, but if that is a problem, look for odorless products.
  • Vitamin C–Decades ago, Linus Pauling popularized the cold-and-flu-protecting properties of vitamin C. Nothing has changed my mind on the value of this supremely important vitamin. For prevention, take at least 1,000 mg a day.
  • Licorice Root Tincture–Take 20 or so drops under the tongue twice a day. Licorice root has long been used as a folk or traditional remedy for stomach ulcers, bronchitis, and sore throat, as well as infections caused by viruses, such as hepatitis. Just a cautionary note on licorice root: don’t take it longer than 10 days and check with your doctor when considering using it if you have high blood pressure (it has the potential to raise blood pressure because of an altering effect on potassium in the body).
  • Resveratrol–Naturally found in the skin of red grapes, this compound helps prevent virus replication. Recommendation dosage: 50-200 mg a day.
  • Curcumin–This celebrated extract from the curry spice turmeric has been repeatedly shown to have a wide and powerful inhibiting effect on many types of microbes, including influenza viruses and herpes simplex virus. Take 250 mg routinely, increasing to 1,000 mg if you are coming down with something. It is interesting to note that the combination of resveratrol and curcumin has been featured in a number of studies showing a synergistic (heightened) effect together against cancer cells.
  • N-acetyl Cysteine (NAC)–This most important amino acid serves as a building block for glutathione, your body’s most natural immune-supporting antioxidant. Research has shown that 1,000 mg a day can significantly decrease the frequency of influenza-like episodes, as well as severity and length of time confined to bed.
  • Astragalus–An incredible adaptogenic root herb, astragalus helps protect the body against physical, environmental, and even emotional stressors. It has a long history of medicinal use in China to strengthen the immune system. As an antioxidant and expectorant, it supports lung and bronchial function. I have been taking it for the last 10 to 15 years. I learned about astragalus from my son, Dr. Drew Sinatra, a naturopathic physician with a keen interest in lung health (he struggled with asthma throughout childhood).

Note: If you take licorice root tincture, and high-dose resveratrol, curcumin, and NAC, it is advisable to use them for four weeks and then skip 3 days during the viral epidemic cycle to give your immune system a rest.

Additionally, I like:

  • Beta-glucans–Biologically active compounds from yeast, fungi, and seaweed, beta-glucans boost the immune system’s ability to destroy pathogens in the small intestine. Studies have shown synergistic potency when using beta-glucans in combination with vitamin C and resveratrol. Take 10 mg daily as a preventative, and 10-20 mg daily at the onset of symptoms.
  • Active hexose correlated compound (AHCC)–a powerful and diverse mushroom formula with acetylated alpha-glucan, AHCC can increase natural killer cell activity. Take 1.5-3 grams daily.
  • Black Elderberry–Used for centuries to help fight colds and flu, black elderberries are rich in polyphenolic compounds called anthocyanins–powerful antioxidant flavonoids with anti-inflammatory properties. Available in syrup and gummy form, elderberry is a convenient immune booster for children and pill-averse adults. Take at first sign of symptoms to reduce the duration.
  • Oil of Oregano–An anti-viral agent, I like a liquid extract and would dose 2 drops under tongue, or mixed with 4 oz (or more) of juice or water 1-2 times daily. If you take capsules, it is best to take it with food to avoid stomach irritation.

Don’t Fall into the Antibiotic Trap

Too many people do. They run to their doctors and ask for an antibiotic at the first sign of a cold or flu. It’s typically a mistake, a treatment that can set you up for another bout of illness, and your doctor should know better.

Colds, the flu, most sore throats, and bronchitis are caused by viruses, microorganisms that invade healthy cells, multiply, and spread. And here’s what people don’t realize: ANTIBIOTICS DO NOT FIGHT VIRUSES. Worse, they can increase the risk of a resistant infection down the road. What’s more, they deplete the very important benign bacteria – probiotics, as they are called–that reside in your intestine and form a major element of your immune system.

What about the Flu Shot?

You may have been wondering why I haven’t mentioned the flu shot even once in this article. Some officials are saying you should get a flu shot to help keep yourself out of the doctor’s office (where coronavirus is more likely to have been), but I don’t believe in it as a primary means of prevention for many folks. From my observation over the years, those who have gotten shots experience colds and flu as much as people who have passed on them.

Moreover, the research I’ve read clearly indicates the flu shot is not very effective–it was estimated to protect against the flu in just 38% during the 2017-2018 season and only 29% of people during the 2018-2019 season. All this said, if you’re elderly, you have a chronic illness like heart disease or you’re at greater risk of pneumonia you may want to get the pneumonia vaccine. Discuss these options with your healthcare provider to find the right solution for you.

Stay healthy!


Dr. Stephen Sinatra

Meet Dr. Stephen Sinatra

A true pioneer, Dr. Sinatra spent more than 40 years in clinical practice, including serving as an attending physician and chief of cardiology at Manchester Memorial Hospital, then going on to formulate his advanced line of heart health supplements. His integrative approach to heart health has changed the lives of hundreds of thousands.

More About Dr. Stephen Sinatra