In a recent study published in the International Journal of Molecular Sciences, researchers assessed the function of micronutrients and metabolites derived from gut microbiota in coronavirus disease 2019 (COVID-19) recovery.

The availability of sufficient micronutrients and gut flora in homeostasis are two of the many positive benefits of a balanced diet on health. Vitamins and minerals provide an immunoregulatory function and participate in biochemical reactions as cofactors and coenzymes; in contrast, the gut microbiota and its metabolites control the cell response directly and indirectly through their interactions with host receptors. The probable causes of this susceptibility are diet and gut microbiota makeup. Its supplementation can help reestablish microbial balance and boost the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and recovery.

Role of Micronutrients in COVID‐19 Infection and sequelae

The present study examined how micronutrients and microbiomes affect COVID-19 infection risk, disease severity, and sequelae.

Through T-cell alterations and the immunological response mediated by antibodies, micronutrient deficiency inhibits the immune response. In respiratory disease, vitamins decrease the cellular burden and viral antigen expression, decrease mitochondrial antiviral signaling (MAVS) and interferon regulatory factor 3 (IRF3) gene expression, and boost nuclear factor-κB (NF-κB) expression. However, adequate vitamin intake controls both immune responses and, in some circumstances, reduces the risk of infections by inhibiting the production of pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α).

Interleukin 6 (IL-6) and interferon (IFN) can also lessen the frequency, severity, and danger of dying from infections like COVID-19. The severity of the illness is determined by the immune system's prompt response to this infection; as such, micronutrients function as immunoregulators and are connected to the immune system's reaction to COVID-19 infection.

Vitamins D, C, and B, as well as some minerals like Zinc, are micronutrient supplements that have a favorable impact on respiratory illnesses, sepsis, and even COVID-19. As a result, the therapy of these patients must include a strategy for monitoring nutritional status and a specific diet to counteract post-COVID-19 micronutrient deficits.

Water‐Soluble Vitamins

Depending on the body's requirement, vitamin C serum concentrations might rapidly drop during infections. High intravenous doses lessen the severity of respiratory tract infections caused by COVID-19 in individuals when it is supplemented. Notably, ascorbic acid can control how SARS-CoV-2 enters its target cells since it can decrease the production of angiotensin-converting enzyme-2 (ACE-2) in the alveolar epithelial cells. Furthermore, vitamin C deficiency has been associated with COVID-19 patient symptoms such as fatigue, pain, cognitive problems, and depression. Intravenous supplementation of vitamin C improves, minimizes, and relieves COVID-19 and post-COVID-19 symptoms, although additional research is required to pinpoint the precise advantages and dosages required.

Fat‐Soluble Vitamins

Like vitamin C, the pool storage of retinoic acid is quickly depleted in response to viral load, leading to fever. There has been no research on the impact of vitamin A on COVID-19 or post-COVID syndrome patients, despite claims about how well it modulates the immune system and viral replication. Lack of vitamin D enables SARS-CoV-2 to persist and replicate in the host. In addition, compared to mild COVID-19 symptoms, severe COVID-19 symptoms were associated with vitamin D shortages.

Recent studies have shown that severe COVID-19 patients with vitamin D deficiency have altered cytokine storms due to changes in the synthesis of cytokines like IL-6, IL-8, IL-12, TNF-alpha, and IFN-gamma. Vitamin E may be a crucial regulator in this disease because of its ability to reduce reactive species during active SARS-CoV-2 infection efficiently.

Water and Electrolyte Imbalance

Dehydration, diarrhea, and vomiting are risk factors associated with fluid distribution and electrolyte imbalance and are frequently present in most severe COVID-19 patients. Furthermore, chest pain and heart palpitations are the two predominant cardiovascular symptoms that COVID-19 patients report. Researchers discovered a considerable relationship between the two illnesses since cardiovascular disease (CVD) is commonly reported by those with COVID-19.

The association could be explained by the principal route through which SARS-CoV-2 enters the human host, the ACE-2 receptor, a component of the renin-angiotensin-aldosterone system (RAAS). Additionally, one of the main causes of heart failure is RAAS. As a result, it is acceptable to say that COVID-19 aggravates and precipitates early-onset CVD. In addition, patients who have already had CVD may acquire a more severe form of COVID-19, which would significantly negatively impact their ability to recover from the post-COVID-19 syndrome.

Gut Microbiota in the COVID‐19 Infection and sequelae

The team also determined that SARS-CoV-2-infected people have higher opportunistic infections, such as Actinomyces, Streptococcus, and Rothia. A negative link was found between Faecalibacterium prausnitzii and Bifidobacterium bifidum, which also has immunomodulator potential and significant anti-inflammatory capabilities that support the host defense. Opportunistic pathogens like Collinsella, Coriobacteriaceae, Enterococcaceae, and Staphylococcaceae are observed in the gut microbiota of critical COVID-19 patients. These pathogens are associated with better health conditions because they produce short-chain fatty acids, but their production is significantly reduced in COVID-19 patients. Due to their inherent resistance to various medicines and their rapid adaptability to chemotherapy, this enormous number of microorganisms may have an impact on the clinical condition of the patients.

Overall, the study demonstrated the evidence of the significance of micronutrients in the immune system's control of viral infections, particularly SARS-CoV-2, and showed their importance as a therapeutic support tool.

Written by

Bhavana Kunkalikar

Bhavana Kunkalikar is a medical writer based in Goa, India. Her academic background is in Pharmaceutical sciences and she holds a Bachelor's degree in Pharmacy. Her educational background allowed her to foster an interest in anatomical and physiological sciences. Her college project work based on ‘The manifestations and causes of sickle cell anemia’ formed the stepping stone to a life-long fascination with human pathophysiology.