The liver and kidneys are two detoxification organs of the human body and are known as “reticent” organs. Therefore, once kidney problems are discovered, it is usually in the middle and/or advanced stages of the disease.

Research shows that COVID-19 can cause kidney damage. Jonathan Liu, a professor of traditional Chinese medicine (TCM) at a Canadian public school, explained on an online program how to avoid kidney damage from COVID-19, and recommended dietary therapy to prevent future kidney dialysis troubles.

According to the Centers for Disease Control and Prevention, patients with chronic kidney disease are at higher risk of becoming seriously ill after being infected with COVID-19. The National Kidney Foundation states that one comprehensive research report showed that between March 11 and April 26, 2020, the proportion of acute kidney injury in hospitalized patients infected with COVID-19 was as high as 56.9 percent—more than double the number (25.1 percent) in 2019.

Liu said that a large proportion of kidney disease is caused by the incidence of other chronic diseases, including:

1. Type 1 or Type 2 diabetes: Diabetes is a hidden incubator of kidney damage— especially Type 2 diabetes, which can sometimes go undiagnosed for up to 10 years. However, during that time red blood cells or protein starts appearing in the urine, an indication that the filter function of the kidneys has been impaired. At this stage, the damage caused by diabetes on the kidneys is almost irreparable.

2. High blood pressure: Long-term high blood pressure will cause glomerulosclerosis, a symptom of kidney sclerosis. At this stage, the glomeruli cannot perform the filter and absorption functions normally, and in the end, dialysis is needed to help remove the toxic substances.

3. Prostate enlargement: An enlarged prostate, kidney stones, or certain cancers can cause urinary tract obstruction and urine reflux, and directly damage the glomerulus, resulting in kidney disease.

4. Repeated infection: Urinary tract infection spreads upwards, causing glomerulonephritis. The current COVID-19 infection causes direct damage to glomerular blood vessels and then the kidneys.

A team of Northwell Health, the largest medical system in New York state, conducted a study on patients with acute kidney injury as a result of COVID-19 complications. It found that out of 5,449 patients hospitalized, 1,993 (36.6 percent) suffered acute kidney damage. The study was published in the July 2020 edition of Kidney International.

Another study published in the Chinese Medical Journal in 2020 found that kidney damage caused by COVID-19 is primarily renal tubular damage. About three percent of hospitalized patients with COVID-19 showed varying degrees of proteinuria, and for patients with underlying chronic kidney disease, massive proteinuria may occur.

This is especially true for elderly patients aged 60 and above. This group had a higher risk of acute kidney injury, manifested as elevated serum creatinine and blood urea nitrogen, an increased risk of developing severe disease, and an increased risk of death.

According to Liu, there are three ways that COVID-19 can attack the kidneys:

1. Attack on renal tubular epithelial tissue that causes direct damage to kidney function.
2. Indirect immune damage: The virus leads to the production of a large number of immune cytokines, causing a systemic inflammatory response, resulting in microcirculation disturbance.
3. Damage to other internal organs: For example, the virus impacts the lungs, causing hypoxemia and hypotension. On the high-risk list are the elderly, people with cardiac insufficiency, diabetes, high blood pressure, and chronic kidney disease.

As for how to avoid kidney damage during the COVID-19 pandemic, Liu puts forward four suggestions:

1. Avoid infection: It is best not to be infected by the virus in the first place.
2. After being infected, give yourself adequate rest and avoid overeating to decrease the burden on the kidneys.
3. Avoid using drugs, because they are metabolized by the kidneys, and any inappropriate usage can increase the chance of their damage.
4. To avoid reverse infection, urinate as soon as the body indicates the need—don’t wait.
5. Control basic diseases, especially chronic diseases such as high blood pressure, diabetes, and heart disease.

Liu says that traditional Chinese medicine (TCM) emphasizes the causes of diseases from the perspective of internal regulation. Long-term and/or severe fear will affect kidney function. The effect of long-term fears on the kidneys may cause pain in the waist, the legs to feel frail, frequent visits to the bathroom, or even incontinence.

Traditional Chinese medicine believes that emotions are closely related to physical health and vice versa. The seven emotions referred to in Chinese medicine are joy, anger, worry, pondering, sadness, fear, and shock. In most cases, the emotions are naturally occurring and without pathological consequences.

However, sudden, severe, or chronic conditions may lead to pathophysiological consequences. For example, sadness and depression damage the lungs, fear and surprise damage the kidneys, anger damages the liver, joy damages the heart, and pondering damages the spleen. Injuries to the internal organs may also lead to emotional disorders.

Liu said that when people have kidney deficiency, they tend to be emotionally fearful, so the kidney qi will be disrupted. At this time, viruses and bacteria more easily invade from outside, because the kidney meridian and the bladder meridian systems are interlaced between the exterior and interior—that is to say—a large part of the energy on the surface to protect the body comes from the kidney meridian system.

Traditional Chinese medicine has found that the body has a “meridian” system, which is responsible for transporting “qi” and “blood” to the whole body. Qi and blood are the basic components that constitute the body and maintain its physiological activities.

Qi is the “energy” or “vitality” that constitutes life in the body, and TCM generally refers to the substance that replenishes nutrients in the body as blood. Qi and blood circulate to maintain the balance and stability of various tissues and organs. When there is an imbalance or deficiency of qi and blood in the body, diseases or other complications may result.

Traditional Chinese medicine believes that the body has 12 main meridians corresponding to the 12 viscera, and from these viscera, it circulates further to the hands, feet, head, and face. If any of the meridians are blocked, the movement of nutrients will be affected, then “evil qi” or “disease qi” (various factors that cause diseases) will have the chance to invade, and abnormalities will appear in the body.

Liu offers four suggestions:

1. Avoid long-term fear: The classic Chinese medicine “Huang Di Nei Jing” says that “fear leads to depression.” Fear will consume the body’s energy, resulting in the body not having enough antibodies to resist viruses.
2. Avoid getting cold: Viruses invade the body when the energy of the body decreases, and cold weather is a factor that reduces that energy.
3. Avoid excessive indulgences: Excessive sexual activity can consume much essence and blood in the kidneys. In TCM, the kidneys govern the collection of the essence. Excessive consumption of essence is prone to energy dissipation.
4. Maintain a benevolent and peaceful state of mind: TCM believes that when a person’s state of mind is in a kind and peaceful state, the meridians of the body are opened, and the energy will be able to communicate with that of the universe.

The kidney is a prime detoxification organ, and food is particularly important to the kidney. Liu listed foods and medicines to avoid:

1. Foods that contain too much salt: Salt is closely related to high blood pressure, and elevated blood pressure can cause direct damage to the kidneys.

2. High-protein food: Protein is an essential nutrient for the body, but long-term intake of high-protein foods will produce excessive uric acid and nitrogen-containing metabolic waste, increasing the excretion burden through the kidneys.

3. Thick soup and strong tea: If the cooking time of soup is too long, the salt, purine, and fat content will become high. Soups frequently eaten as such can cause hyperuricemia, which can lead to kidney disease and even gouty renal insufficiency. Stewed soups, strong tea, coffee, and high-sugar beverages can cause kidney disease, so you need to be vigilant.

4. Various kinds of Western and Chinese medicine: Liu says that medicine contains 30 percent poison, and all medicines must be prescribed by a doctor.

TCM treats kidney diseases by improving the body’s self-healing mechanism and stabilizing the body’s energy system. Liu pointed out that Chinese medicine has three methods for treating kidney disease:

1. Sweating to relieve the exterior: In the early stage of kidney disease, when it is difficult to move the bowel, in the acute inflammation period, the body’s water metabolism can be adjusted through the treatment of sweating to relieve the exterior.
2. Regulating and nourishing kidney qi method: Patients with chronic kidney disease who show a deficiency of kidney qi can use Liu Wei Di Huang Pills for nourishing kidney yin, and Shenqi pills for replenishing kidney yang, and then choose different Chinese medicines for treatment according to the condition and constitution.
3. Purging turbidity method: Patients with chronic kidney disease have a large amount of metabolic waste, especially protein metabolites, such as creatinine and blood urea nitrogen, which cannot be excreted in the blood. Through the method of purging turbidity with Da Huang Fu Zi Decoction, these toxins can be effectively reduced in the body.

In terms of diet and health care, Liu recommends the concept of nutrition by Thomas M. Campbell II, and his father, T. Colin Campbell, authors of  “The China Study: Revised and Expanded Edition: The Most Comprehensive Study of Nutrition Ever Conducted,” a revolutionary book about diet and health.

Traditional Chinese medicine believes that “black color enters the kidneys.” Liu suggested that if you want to replenish kidney energy, you can eat more black foods, such as black sesame, fungus, black rice, and black beans, which can nourish the kidneys and increase blood circulation. You can also eat more walnuts, leeks, and shrimp, and drink plenty of water to metabolize harmful substances from the body.

*Some of the herbs mentioned in this article may be unfamiliar, but they are generally available in Asian supermarkets.

Note: Because different people have different physiques, it is recommended to consult your doctor or a TCM expert.