Supplementing your diet with yogurts filled with probiotics and supplements may do nothing to improve your health, a study shows.
The market for "good bacteria" products has grown in recent years as scientists begin to discover that our intestinal health is important, affecting everything from sleep patterns to brain function.
But new research from the Weizmann Institute of Sciences in Israel, a leader in the field, confirms the suspicion of many scientists: that there is no one-size-fits-all probiotic & # 39; to balance everyone's bacteria.
They discovered that the only way to know who will benefit from certain products is by performing personalized invasive tests, since the current method (testing of stool samples) does not say much about a person's intestinal health.
However, Eran Elinav insists that we already have the technology at our disposal to create personalized intestinal health tests, and you can imagine that something will be available globally & # 39; in the near future & # 39;
New research from the Weizmann Institute of Sciences in Israel, a leader in the field, confirms the suspicion of many scientists: that there is no one-size-fits-all probiotic & # 39; to balance the bacteria of all
"The future is here," Dr. Elinav, an immunologist at Weizmann, told DailyMail.com.
"People have been very supportive of probiotics, even though the literature that underlies our understanding of them is very controversial.
"We wanted to determine if probiotics like the ones you buy in the supermarket colonize the gastrointestinal tract the way they're supposed to, and then if these probiotics are having any impact on the human host.
"Surprisingly, we saw that many healthy volunteers were really resistant because probiotics could not colonize their gastrointestinal (GI) tracts.
"This suggests that probiotics should not be universally given as a" one size fits all "supplement. Instead, they could be tailored to the needs of each individual."
Dr. Elinav and his team have been pioneers in the increasingly popular field of microbiome research.
His most influential article is cited as the basis of the most important studies at this time in intestinal research around the world, showing how individualized intestinal bacteria are.
Published in Cell in 2016, the study showed that the gills of some people are built to develop with ice cream, while others must continue with rice or kale.
By studying 800 people, they discovered that some people experienced a greater surge of blood sugar after eating white bread or rice than when they ate ice cream.
It was an important advance in intestinal research that shows that those who prescribe popular diets may not be meeting the individualized needs of their instinct.
For this study, Dr. Elinav and his team tried to demonstrate that a general approach to probiotics may be useless for many.
Essentially, they demonstrated that the concept of taking & # 39; probiotics & # 39; As a general basic approach to good health is like taking a handful of generic medications for a disease, then encouraging your friends to take the same cocktail of generic medications for any disease.
It's not a perfect analogy: probiotics will not have deadly consequences, as pharmaceutical drugs might have.
But they can be useless, harmful and probably a waste of money.
In the first study, 25 human volunteers underwent endoscopies and upper colonoscopies to sample their initial microbiome in regions of the intestine. Fifteen of those volunteers were divided into two groups.
The first group consumed generic probiotic strains, while the second group received a placebo.
Both groups underwent a second round of endoscopies and upper colonoscopies to evaluate their internal response before being followed for another two months.
Probiotics successfully colonized the gastrointestinal tracts of some people, called "persistent", while the "resistant" intestinal microbiomes expelled them.
Patterns of persistence and resistance would determine whether probiotics, in a given person, would affect their indigenous microbiome and human gene expression.
The researchers could predict whether a person would be persistent or resistant simply by examining their basal microbiome and the profile of intestinal gene expression.
They also found that feces only partially correlate with the functioning of the microbiome within the body, so relying on feces as was done in previous studies for many years could be misleading.
The coauthor, Professor Eran Segal, a computational biologist, added: "Although all of our volunteers who consume probiotics showed probiotics in their stools, only some of them showed them in their intestines, which is where they should be.
"If some people resist and only some people allow it, the benefits of standard probiotics that we all take can not be as universal as we once thought."
"These results highlight the role of the intestinal microbiome in driving very specific clinical differences between people."
The second study questioned whether patients should take probiotics to counteract the effects of antibiotics, as they are often told they must do so to repopulate the gut microbiota after it has been removed with antibiotic treatment.
It involved 21 volunteers in an antibiotic course and was then randomly assigned to one of three groups.
The first was a group of "observe and wait" that allowed its microbiome to recover on its own, while the second received the same generic probiotics used in the first study.
The third group was treated with a fecal microbiome autotransplant (aFMT) formed by its own bacteria that had been collected before administering the antibiotic.
After the antibiotics had cleared the way, standard probiotics could easily colonize everyone's intestine in the second group.
But this probiotic colonization prevented the normal microbiome and the gene expression profile of the host from returning to normal for months afterward.
In contrast, the aFMT resulted in the gut microbiome and the genetic program of the third group returning to normal within a matter of days.
Dr. Elinav said: "Contrary to the current dogma that probiotics are harmless and benefit everyone, these results reveal a potentially new adverse side effect of the use of probiotics with antibiotics that could even have long-term consequences.
"On the contrary, replenishing the gut with the microbes themselves is a personalized treatment designed by Mother Nature that led to a total reversal of the effects of antibiotics."
Dr. Segal added: "This opens the door to diagnoses that would take us from a universal empirical consumption of probiotics, which seems useless in many cases, to one that adapts to the individual and can be prescribed to different individuals depending on their characteristics. initials". . & # 39;