The researchers investigated specific health claims in more detail, checking these claims against the Cochrane database. Although websites make claims about probiotics treating a range of ills, the evidence is severely lacking.
To date, evidence only supports the use of probiotics to treat a handful of conditions, including infectious diarrhea and necrotizing enterocolitis in preterm infants. Even in these cases, it is necessary for scientists to do more research.
Overall, 93 of the 150 websites claimed that probiotics could enhance the immune system. In reality, as the authors explain, this “has been barely investigated in clinical trials.”
Similarly, a significant number of websites claim that probiotics might help relieve mental disorders and reduce the risk of cardiovascular disease. Again, scientists have carried out very little research into these topics.
In all, there were 325 specific health claims on the webpages that the scientists investigated. Scientific evidence substantiated only 23%, and 20% had no evidential support to back them up. These findings are important, as the authors explain:
“In the current era where distrust in medical experts and health authorities is widespread, individual consumption of over-the-counter health products is largely guided by information collected on the internet.”
They continue, “Since probiotics escape scrutinization by regulatory authorities, it is of utmost importance to get insight into the level of trustworthiness provided by online information on their benefits and risks.”