Recent studies have suggested gut dysbiosis is linked to the movement of gut bacteria into the blood during a COVID infection. In mice, COVID caused changes in a variety of parameters associated with gut barrier permeability, meaning things can theoretically move more easily through the gut wall.
In 20% of human COVID patients in this same study, certain bacteria from the gut had migrated into the bloodstream. This group was at higher risk of developing a secondary infection in the blood.
Research is now also showing that dysbiosis following COVID may contribute to long COVID, with gut dysbiosis more prevalent in patients presenting with long-term COVID symptoms. This makes sense because dysbiosis seems to put the body in a heightened and constant state of inflammation – something that’s associated with chronic COVID symptoms.
Supporting your immunity
As we continue to develop a more comprehensive understanding of gut microbes and their role in inflammation, how can you help keep your immune system healthy to protect yourself against COVID and other infections?
Certain nutrients, including vitamins A, C, D and E as well as iron, zinc and omega-3 fatty acids, all have positive effects on immune responses against viral infection.
A Mediterranean diet, which is rich in vitamins, minerals and dietary fibre, has an anti-inflammatory effect in the gut. Interestingly, a strain of bacteria known as Faecalibacterium prausnitzii is key to immune regulation. It’s frequently low in the western diet, but abundant in the Mediterranean diet.
Ideally you should avoid too many refined cereals, sugars and animal fats, which can all heighten inflammation in the body.
Probiotics, supplementary blends of live bacteria, may also have benefits. A blend of bacterial strains Lactiplantibacillus plantarum and Pediococcus acidilactici was shown to reduce the quantity of virus detected in the nasal passage and lungs, as well as the duration of symptoms in COVID patients.
This combination also significantly increased the production of COVID-specific antibodies, suggesting probiotics act directly by interacting with the immune system, rather than solely changing the composition of the gut microbiome.
Finally, moderate exercise can also help support the immune system to fight COVID.