With COVID-19 spreading across the globe, you may be wondering how to bolster your defenses against this dangerous pathogen and whether the ketogenic diet will help or hinder your efforts. Does the ketogenic diet have antiviral or immune-boosting properties? The evidence is fairly limited, but the answer is, the ketogenic diet might be a helpful line of defense.
Recent research published in the Journal of Immunology found that mice on a keto low-carb diet fared better against the influenza virus (flu) than mice on a high-carb diet. To be clear, COVID-19, the disease caused by the new coronavirus, isn’t the flu. (And humans aren’t mice). But since both influenza and coronavirus are respiratory viruses, it’s worth exploring.
In this article you’ll learn about the novel coronavirus, how viral immunity works, and a few potential mechanisms by which keto may help the immune system.
Quick disclaimer: This article is for informational purposes only. Nothing here should be taken as medical advice, or as recommending a ketogenic diet to treat COVID-19.
What Is Coronavirus?
Coronaviruses are a family of viruses that cause respiratory infections in humans. Certain strains of coronavirus even cause the common cold.
When you hear about coronavirus today, you’re hearing about a novel strain called SARS-CoV-2. (Severe acute respiratory syndrome coronavirus 2). This particular virus originated in an animal market in Wuhan, China (probably from a bat), and is currently spreading through the human population.
SARS-CoV-2 causes a disease called COVID-19. The symptoms of COVID-19 are similar to those of the flu – fever, sore throat, cough, and shortness of breath – but the mortality rate (estimated at 0.25 percent to 3 percent by the CDC) is significantly higher, especially among older people.
The CDC believes SARS-CoV-2 spreads primarily through water droplets dispersed via the coughs and sneezes of the infected. To avoid these droplets, you’re advised to stay six feet away from potentially infected people. COVID-19 may also spread through surface contact (i.e., touching your face after touching the virus) or potentially through airborne transmission, in which the virus transmits (even after long periods) through the air.
In general, the CDC and other authorities are recommending social distancing (avoiding others, especially sick people, when possible) to prevent the virus from spreading. Please visit the CDC website for the latest coronavirus news and for tips on avoiding exposure. The rest of this article is devoted to viral immunity.
How Viral Immunity Works
When you’re exposed to a virus, it may take hours, days, or even weeks to manifest symptoms. This period from exposure to symptoms is called the incubation period. (According to research published March 10, 2020: COVID-19 has a median incubation period of 5.1 days).
Yet, even before you experience symptoms, your immune system has taken steps. The first step is to sense the virus. All the time, you have sensor proteins circulating throughout your body on high alert for pathogens. When they find one, they signal what’s called an innate immune response, which may include:
- Immune-signaling molecules like cytokines and interferons
- White blood cells like natural killer cells or macrophages
- Other forms of inflammation
We won’t be diving too deeply into these immune factors. Just understand that they’re part of your initial immune response, which is often sufficient to eliminate the virus.
But not always. When symptoms start to develop, it usually means the virus has replicated in significant numbers.
At this point, your adaptive immune response gets activated. This response includes antibodies, T cells, and various forms of white blood cells, which specifically target the virus. Unfortunately, it takes about three to 10 days to form antiviral antibodies like IgG (Immunoglobulin G) and IGA (Immunoglobulin A).
That’s why vaccines take days or weeks to kick in. The adaptive immune system needs time to muster its forces.
Speaking of adaptive immunity, let’s look at how the keto diet influenced T-cell activity in virally infected mice.
Keto and the Flu Virus
The best evidence for keto fighting viruses comes from rodents. In 2019, the aforementioned study published in the Journal of Immunology, mice were fed either a high-carbohydrate diet or a low-carbohydrate keto diet for seven days, then intranasally infected with H1N1 influenza virus.
The results were striking. At four days post infection, all the high-carb mice had died, yet half the mice on the keto high-fat diet survived. Keto diet mice also lost less weight and had lower levels of the virus in their blood.
Researchers believe the keto diet, where the body is in a perpetual state of ketosis and relies on ketones for energy, protected the mice by increasing immune particles called gamma-delta T cells in the lungs. The gamma-delta T cells, in turn, boosted mucous production that limited viral spread.
While this result doesn’t mean a keto diet has the same effect in humans, it is promising. Still, more research is needed.
Other Ways Keto May Fight Viruses
Other than the anti-flu effect shown in mice, the ketogenic diet has other benefits which may be useful in combating viruses. These include:
- Decreased inflammation. The keto diet has been shown to block an immune signaling complex called the inflammasome in mice. An activated inflammasome is linked to increased flu severity.
- Weight loss. Obesity is linked to compromised immune function. Much evidence suggests that the keto diet stimulates weight loss in obese and diabetic populations.
- Diabetes prevention and reversal. Along with obese people, diabetics also tend to have poor immune systems. Multiple clinical trials suggest that keto can regulate blood sugar and help reverse type 2 diabetes.
- Fat metabolism. When you’re fighting infection, you partially lose your ability to use glucose for energy. This state of insulin resistance, however, may be mitigated on a keto diet. (Keto shifts your body away from burning glucose and towards burning fat).
- Protein intake. A modified ketogenic diet has you eating about 25-30 percent of your calories from protein. Protein supplies the necessary materials to produce antibodies, cytokines, macrophages, and many other immune cells.
- Micronutrients: Provided you include animal protein, organ meats, and non-starchy vegetables in your keto diet, you’ll be consuming the most important vitamins and minerals for immune function. These include zinc, selenium, iron, copper, vitamin A, vitamin C, vitamin E, vitamin B6, and folate.
The Final Word
With the pandemic circulating the globe, the time to support your immune system is now. Assuming it doesn’t increase your risk of exposure, do your best to keep up your health routine. This means eating a nutritious diet low in carbohydrates, exercising, and getting plenty of sleep.
Early evidence suggests that a keto diet, where the body produces and burns ketone bodies for energy, may help with viral immune defense. (In mice with flu, at least). A whole foods keto diet also provides raw materials necessary for healthy immune function. However, the best way to steer clear of viruses like COVID-19 is to avoid exposure to them. Turn to the CDC for guidance on this. Thanks for reading, and stay healthy.