McCarty and DiNicolantonio list several nutrients available in supplement form that may be of particular benefit against COVID-19, including the following (below). For more details about each, see the full-text paper published in Progress in Cardiovascular Diseases:
N-acetylcysteine (NAC) — Encourages glutathione production, thins mucus, lowers your chances of influenza infection and reduces your risk of developing severe bronchitis
Elderberry extract — Known to shorten influenza duration by two to four days and reduce the severity of the flu. According to the authors:
“Given that elderberry is a very rich source of anthocyanins, there is reason to suspect that its impact on viruses might be mediated, at least in part, by ferulic acid, a prominent metabolite that appears in plasma following anthocyanin ingestion.”
Spirulina — Reduces severity of influenza infection and lowers influenza mortality in animal studies. In a human trial, spirulina significantly lowered the viral load in patients with HIV infection.
Beta-glucan — Reduces severity of influenza infection severity and lowers influenza mortality in animal studies.
Glucosamine — Upregulates mitochondrial antiviral-signaling protein (MAVS), reduces severity of influenza infection severity and lowers influenza mortality in animal studies.
Selenium — “Since selenium is an essential cofactor for certain peroxidases, and selenium deficiency has been endemic in certain regions of China and other parts of the world, insuring adequacy of selenium nutrition might also be appropriate in this context,” McCarty and DiNicolantonio note, adding:
“Selenium deficiency also increases the rate at which viruses can mutate, promoting the evolution of strains that are more pathogenic and capable of evading immune surveillance.”
Zinc — Supports “effective function and proliferation of various immune cells,” lowering mortality in the elderly by 27%.
Lipoic acid — Helps boost type 1 interferon response. As explained in a 2014 paper:
“Type I interferons (IFNs) activate intracellular antimicrobial programs and influence the development of innate and adaptive immune responses … (IFNs) are polypeptides that are secreted by infected cells and have three major functions.
First, they induce cell-intrinsic antimicrobial states in infected and neighboring cells that limit the spread of infectious agents, particularly viral pathogens. Second, they modulate innate immune responses in a balanced manner that promotes antigen presentation and natural killer cell functions while restraining pro-inflammatory pathways and cytokine production. Third, they activate the adaptive immune system, thus promoting the development of high-affinity antigen-specific T and B cell responses and immunological memory. Type I IFNs are protective in acute viral infections but can have either protective or deleterious roles in bacterial infections and autoimmune diseases.”
Sulforaphane — Helps boost type 1 interferon response.
A 2005 study in The Journal of Infectious Diseases also found resveratrol has the power to inhibit the replication of influenza A virus, significantly improving survival in influenza-infected mice. According to the authors, resveratrol “acts by inhibiting a cellular, rather than a viral, function,” which suggests it “could be a particularly valuable anti-influenza drug.”