The pandemic has shown mounting evidence how comorbidities such as obesity, the risk conditions it causes such as type 2 diabetes, hypertension, and cardiovascular disease contribute to a high risk of mortality that results as a result of complications caused by COVID-19.
The outbreak is an acute respiratory illness that is caused by the coronavirus, (SARS-CoV-2 ). Acute respiratory infections are one of the leading causes of morbidity around the world.
The novel coronavirus virus (COVID-19) is posing a serious challenge to the healthcare systems in India and across the globe, with an enormous impact on health conditions and loss of lives. Notably, obesity and its related comorbidities are strictly related to worse clinical outcomes of COVID-19 disease.
There is a growing interest in the clinical use of ketogenic diets (KDs), particularly in the context of severe obesity with related metabolic complications. KDs have been proven effective for a rapid reduction of fat mass, preserving lean mass, and providing an adequate nutritional status. The increase of ketone bodies in blood exerts important anti-inflammatory and immunomodulating effects, which is useful to prevent infection and potential adverse outcomes and reduces the risk of mortality due to COVID-19 disease.
The favorable effects of the ketogenic diet on inflammatory cytokines cause NLRP3/inflammasome activation due to a viral infection which results in a massive secretion of proinflammatory cytokines which can prevent cytokine storm syndrome.
We will highlight the importance of the Very Low-Calorie Ketogenic Diet (VLCKD) for a rapid reduction of several risk factors for COVID-19, such as obesity and its associated risk conditions such as type 2 diabetes, hypertension, cardiovascular disease. We will also focus on the positive effects of ketone bodies on inflammation, immunity, metabolic profile, and cardiovascular function.
It is vital that a rapid reduction of all modifiable risk factors, especially the ones associated with obesity, should be a pillar of public health policies and interventions, in view of any future waves of SARS-CoV-2 infection.
Risk Factors related to COVID-19
Data from previous viral outbreaks such as H1N1 in 2009 have also indicated the negative impacts of obesity on the host’s immune system making it vulnerable to infectious diseases.
Excess adiposity (fat mass) drastically alters the normal functioning of the body and disrupts the balance between pro-inflammatory and anti-inflammatory immune cells, primarily leaning to the former. This leads to chronic low-grade inflammation which is likely amplified by acute inflammation arising out of COVID-19 resulting in severity and dangerous outcomes.
Among risk factors for SARS-CoV-2, numerous studies have also identified a specific association of COVID-19 fatality with the presence of comorbidities, particularly obesity, diabetes, hypertension, and cardiovascular disease.
In addition, it is worth mentioning that the increase of sedentarism due to lockdown enforced in several countries during the pandemic, displayed deleterious effects on skeletal muscle metabolism, inducing insulin resistance, fat deposition, and low-grade systemic inflammation, with an overall worsening of metabolic parameters, glucose control, and inflammatory status.
In this regard, sarcopenic obesity, characterized by the coexistence of excessive adiposity and low muscle mass, is strongly associated with increased cardiovascular risk, insulin resistance, and low-grade inflammation; therefore, it represents, together with the inadequacy of nutritional status, a condition associated with increased susceptibility to viral infection.
During the lockdown, the lifestyle and eating habits of a great part of the population have dramatically changed. It is known that unhealthy nutritional habits, rich in fat and carbohydrates, are associated with obesity. Moreover, the decreased amount of physical activity during quarantine has affected a significant size of the population’s general health. Therefore, there is a real risk that a higher number of patients with obesity are exposed to the Sars- Cov2 infection.
Health Impacts we are facing with Obesity at Present
Obesity affects several critical functions, characterizing an increased vulnerability towards COVID-19. Obesity state alters immune responses to viral infection, determines a chronic, low-grade inflammation, and worsens glucose tolerance and oxidative stress with adverse effects on cardiovascular function.
Notably, a recent report showed that adipose tissue expresses very high levels of transcripts for ACE2, an enzyme attached to the membranes of cells located in the lungs, arteries, heart, kidney, and intestines, that act as the receptor for the SARS-CoV-2 virus and allows it to infect the cell. This raises the question of whether adipose tissue may represent a reservoir of SARS-CoV-2, and a strategical site to amplify the cytokines cascade triggered by viral infection.
Inflammation: Friend or Foe in these times
It is evident that the abnormal release of proinflammatory cytokines and chemokines, induced by SARS-CoV-2 infection, is central to the fatal outcomes of COVID-19.
Obesity, a result of excess adipose tissue (fat mass) is characterized by a low-grade chronic inflammation state. This type of inflammation should be carefully considered in order to understand the risks of obesity since several key inflammatory markers are strictly linked with an increased risk of adverse outcomes in obesity-associated comorbidities.
There is a large body of evidence indicating a positive correlation between C-reactive protein, known as a marker of systemic inflammation, and overall body composition. Moreover, key inflammatory cytokines, show a positive association in obese individuals, further supporting the strict connections between inflammation and obesity.
The Very Low Calorie Ketogenic Diet and its integral part against COVID-19
Due to changes in lifestyle behavior and excess food intake nutritional advice is still poorly considered in public health discussions about the prevention or reduction of Sars-Cov-2 infection risk and related complications. The ketogenic diet may play a role in modulating both innate and adaptive immune cells, which synergistically protect the host against pathogens’ assaults.
Incorporating the Very Low-Calorie Ketogenic diet causes a metabolic shift which results in increased resistance to mitochondrial stress, an improvement in antioxidant defenses, augmented autophagy, a natural, regulated mechanism of the cell that removes unnecessary or dysfunctional components and DNA repair, and a decreased insulin secretion. In this context, ketogenic diets represent a nutritional approach for improving the immunological response to Sars-CoV-2 infection in high-risk populations
The reduction in carbohydrate intake in the VLCK Diet is associated with significant suppression of hepatic glucose production, due to a marked improvement in hepatic insulin sensitivity. VLCKD should be part of a multidisciplinary approach for metabolic rehabilitation in patients.
The VLCK Diet exerts most of its therapeutic effects by increasing the plasma levels of ketone bodies. The diet has been found effective in lowering blood pressure, due to the increased natriuresis which is associated with urine excretion of ketone bodies. Physical exercise also seems to be a potential factor of the aforementioned favorable effects of the diet, such as the improvement of glycaemic control, body composition, reduced liver fat content, and in general, improved metabolic health.
Considering the role of inflammasome activation in triggering the systemic inflammatory cascade observed in COVID-19 patients, approaches based on increasing plasma ßOHB, such as incorporating the VLCK Diet, should be taken into account to prevent the development or the progression of the cytokine storm syndrome, a condition where the immune system is producing too many inflammatory signals, sometimes leading to organ failure and death.
There are multiple mechanisms through which ketone bodies might impact severe viral infections such as COVID-19 disease. We believe the ProGen Method’s protocol, the VLCK Diet-induced increase in endogenous ketone bodies could represent a more valuable strategy to prevent Sars-Cov2 infection and adverse outcomes in obese patients, particularly in the current context of a prolonged pandemic emergency.
“According to the National Institute of Health, the prevalence of overweight and obesity in India is increasing faster than the world average. The prevalence of overweight people increases from 8.4% to 15.5% among women between 1998 and 2015, and the prevalence of obesity increased from 2.2% to 5.1% over the same period”. The pandemic has given us a glimpse into the healthcare sector in India and the general health condition of the masses.
Indeed, prevention and/or correction of all risk conditions associated with serious COVID-19 disease is mandatory, in consideration of new waves of infections, in the absence of effective pharmacological therapies and delay in vaccination. This could be obtained with a nutritional strategy aimed to induce fast fat mass loss, to reduce chronic inflammation, hepatic and systemic insulin resistance, and to improve nutritional status, cardiovascular health, immune response, glucose homeostasis and blood pressure control.
The multidisciplinary approach of the ProGen Method, is a well-structured and personalized VLCKD regimen that could help a progressive nutritional education and rehabilitation in obese patients, providing an effective tool to modify lifestyle behavior, supporting a long-term control of body weight, and favoring a reduction in all associated risk factors for potentially severe complications related to Sars-Cov2 infection.
During this difficult pandemic era, the adoption of lifestyle preventive measures is mandatory, and should be carefully implemented.
(The information provided above is based on the research by the Journal of Translational Medicine and the scientific approach of the ProGen Method)