New study: eating probiotics can make immunisation more effective
According to the study, these probiotic tablets helped the body improve its own defences against the COVID-19 virus. The preparation improved the effectiveness of vaccination. Photo: BioGaia AB
Many people fell ill with COVID-19 despite being vaccinated. A new study shows that it may be possible to reduce this risk – by taking probiotic tablets.
“We saw that probiotics increased the levels of antibodies against the virus,” says Richard Forsgård, researcher at Örebro University.
Read the full research article in Gut Microbes.
The study is co-funded by the Knowledge Foundation, BioGaia AB and the EU research programme MSCA.
The vast majority of people vaccinated during the COVID-19 pandemic did not become ill with the disease. However, because so many people were vaccinated, it became clear that some people got sick despite receiving two doses. In Sweden alone, the Public Health Agency reported thousands of such cases.
These cases are called breakthrough infections and are a known phenomenon in vaccinations. No vaccine is 100% effective. However, vaccines given for COVID-19 were often partially effective, even against breakthrough infections – providing good protection against becoming seriously ill.
During the pandemic, a team of researchers led by Örebro University worked to investigate the possibilities of improving the body’s defences against the virus that leads to the COVID-19 disease. Their idea was that probiotics – preparations with living bacteria that strengthen the intestinal flora – could play an important role.
First study of its kind
The results are now finalised, audited and published.
It turns out that those who ingested a specific probiotic in combination with vitamin D had a better defence against the coronavirus. An essential part of the body’s defence, the immunoglobulin A antibody, increased. This antibody, IgA for short, is found mainly in the mucous membranes of the respiratory and gastrointestinal tract.
“We observed that those who took probiotics had a higher level of virus-specific IgA antibodies more than four weeks after infection. This is interesting because previous studies show that IgA antibodies are important in preventing breakthrough infections,” says Richard Forsgård.
The study involved 159 participants, some of whom received probiotics and vitamin D, while a control group received vitamin D alone. At the start of the study, all were healthy and unvaccinated. Fifteen participants became infected, and 95 received one or more vaccinations while being followed by the research team.
The study is, as far as is known, the first of its kind. Although relatively small, the results are consistent.
Richard Forsgård and Robert Brummer have led the research team at the Nutrition-Gut-Brain Interactions Research Centre at Örebro University.
New ways to reducebreakthrough infections
“These results are more robust than we had thought. I want us to do much more research in this area because this can help people cope better with viral infections. Probiotics also have no harmful side effects,” says Robert Brummer, Professor of Gastroenterology and Clinical Nutrition at Örebro University.
The pandemic is over, but the lessons learnt from the study may now lead researchers towards new ways to reduce breakthrough infections and thus make existing vaccines more effective.
“In this case, it was COVID vaccines, which are very effective. However, other types, such as influenza vaccines, are less effective for older people or those with weakened immune systems. This would be an exciting area for further research,” says Richard Forsgård.