Optimising the Immune System
There is increasing evidence that being in a good state of health is one of best ways to protect yourself from succumbing to a severe COVID-19 infection and many other infections. Given that there is no vaccine that is proven to give lasting protection, and the drugs that are currently used are not always effective we all need to be proactive in optimising our health.
Things we’ve learnt from the COVID-19 pandemic so far include:
- Drugs and vaccines take time to produce, test and distribute so may not be the best or only way to deal with a novel global pandemic.
- People with underlying health conditions including diabetes, cardiovascular diseases, obesity, and chronic lung conditions, experience more severe and longer lasting symptoms and side effects, and are more likely to die than those who are healthy.
- Those with poor nutritional status are more likely to be immuno-compromised and susceptible to infection, and are likely to have worse outcomes.
- Severe COVID-19 infections usually involve the overproduction of proinflammatory cytokines which can lead to multi-organ failure, and eventually death (1,2).
The Role of Supplements
Here are some reasons why you may want to supplement your healthy diet with vitamins, minerals and nutraceuticals:
- The immune system cannot function efficiently without an adequate intake of vitamins, minerals and trace elements.
- Nutrient deficiencies suppress immune functions and increase susceptibility to infections, with increased risk of serious illness or death.
- Infections aggravate micronutrient deficiencies by reducing nutrient intake, increasing losses, and interfering with utilization of nutrients by altering metabolic pathways.
- Anti-inflammatory nutrients are of particular importance due to the damage done by the cytokine storm seen in severe COVID-19 infections.
- Nutritional supplements are widely available, have a long history of safe use and have negligible side effects if taken in tried and tested doses.
For these reasons vitamins, minerals, probiotics, and nutraceuticals are being considered as a safe and effective way of reducing the risk of Sars-CoV-2 infection and reducing the symptoms of COVID-19 including systemic inflammation and endothelial damage (3,4).
Here we will look at which supplements can support your immune system and reduce your risk of becoming seriously ill.
The B vitamins are actively involved in the healthy functioning of the immune system (5) and are specifically required for cytotoxic cellular immunity and to modulate T cell responses (6).
Studies indicate that vitamin C may both prevent and alleviate infections caused by bacteria and viruses. Vitamin C is a powerful antioxidant that scavenges free radicals as well as restoring other antioxidants. It may reduce virally induced damage, prevent viral replication and down-regulate inflammation. In addition patients with acute viral infections have low circulating vitamin C levels, as vitamin C is used up more quickly during illness (7,8,9). Higher doses than usual are needed to have an impact on viruses with 6-8 g per day being shown to be effective. It should be noted that high doses of vitamin C can cause loose bowels.
Vitamin D deficiency is correlated with a higher susceptibility to infections. Vitamin D plays an important role in our immune response and supports an anti-inflammatory cytokine profile (9,10).
When zinc deficiency was identified in the 1960s it quickly became clear that zinc is vital for a healthy immune system. Zinc has anti-inflammatory and antioxidant properties. Zinc is important for the maintenance and development of both the innate and adaptive immune system (6,11). Zinc deficiency reduces our defences against infection and increases the risk of inflammation (12). Zinc has also shown specific immune-modulatory effects in viral respiratory infections (13).
The essential fats are vital for many aspects of health. Omega 3 fats have an anti-inflammatory effect and are actively involved in the proper functioning and strengthening of the human immune system against viral infections (5).
Supplementing with curcumin, derived from turmeric, has been shown to support the immune system and reduce inflammation (14,15). Recent research has shown that a combination of vitamin C, curcumin and glycyrrhizic acid (from liquorice) may be helpful in regulating the immune response to combat CoV infections and in inhibiting excessive inflammatory responses potentially preventing the onset of a cytokine storm (16).
Probiotics such as Lactobacillus and Bifidobacterium are being used in the treatment and prevention of many conditions and in promoting human health generally. They have recently been found to decrease the risk and duration of respiratory infections and protect against microbial pathogens, including viruses (17). Probiotics may exert their antiviral effects directly by interacting with the virus or by stimulating the immune system to fight them (18). Interestingly, some patients with COVID-19 have been found to have decreased beneficial bacteria such as Lactobacillus and Bifidobacterium (19).
Protein is important for repair and maintenance of body tissue, hormones, enzymes, antibodies and for a healthy immune system. Good sources of protein include meat, fish, eggs, nuts, seeds, pulses, tofu and tempeh. Protein powders and protein bars can be useful additions to the diet especially at times when extra support is needed.
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Abdelhamid AG et al. Probiotic Lactobacillus and Bifidobacterium strains possess safety characteristics, antiviral activities and host adherence factors revealed by genome mining. EPMA J. 2019 Sep 5;10(4):337-350
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