Antibiotics are essential to combat bacterial infections, but they are also usually accompanied by digestive side effects such as nausea, diarrhea or abdominal pain..

Faced with this, many people automatically turn to probiotic supplements to “repair” the intestinal microbiota. However, the scientific evidence is not as clear as it seems.

This is how the doctor explains it Trisha Pasrichagastroenterologist and professor of medicine at Harvard Medical School, in a column published by Washington Post.

Do probiotics work?

“There is no conclusive data demonstrating the effectiveness of probiotic supplements, and there is worrying scientific evidence that suggests they may even delay recovery.”warns the specialist.

As Pasricha explains, antibiotics not only eliminate the bacteria responsible for an infection, but also beneficial microorganisms that live in the intestine and perform essential functions, such as helping to ferment fiber and strengthening the immune system.

Therefore, digestive discomfort during treatment “is an expected, although unfortunate, side effect of many antibiotics,” he points out.

Even so, he clarifies that This does not necessarily mean that there is permanent damage to the intestinal microbiota..

The specialist maintains that the microbiome (the set of bacteria and genetic material present in the intestine) usually recovers naturally in a few weeks.

However, recent research shows that some broad-spectrum antibiotics may produce longer-lasting changes.

A Swedish study published in the scientific journal Nature Medicine analyzed the microbiomes of almost 15 thousand people and concluded that certain antibiotics can produce persistent alterations even years after being used.

Among those most associated with these changes were clindamycin and some fluoroquinolones.

So do probiotics work? For Pasricha, the answer is, in most cases, no..

A 2023 meta-analysis found that “taking probiotics during antibiotic treatment has very little effect.”

Additionally, he cites a study published in 2018 in the journal Cell, which observed that people who took probiotics after using antibiotics took longer to recover their original microbiome.

Tips for the microbiota

Instead of supplements, the gastroenterologist recommends focusing on habits supported by scientific evidence to strengthen the intestinal microbiota.

The first is to follow a diet rich in fiber. “Your microbes ferment the fiber and, in turn, produce beneficial short-chain fatty acids,” he explains.

It also emphasizes the importance of consuming different types of vegetables and sources of fibersince dietary diversity favors greater microbial diversity.

Another tip is to incorporate fermented foods such as Greek yogurt or kimchi daily.

Pasricha highlights a clinical trial conducted by Stanford University researchers that showed that People who ate more fermented foods had greater microbial diversity and lower levels of inflammatory proteins in the blood.

If you need antibiotics, take them

Despite the possible effects on the intestine, the specialist emphasizes that antibiotics continue to be essential tools in medicine.

“If you need them, take them,” he says. Of course, he insists that they should be used only when they are really necessary. and always complete the indicated treatment to avoid bacterial resistance.

“Antibiotics do not fight viruses, only bacteria,” Pasricha recalls.

Therefore, ordering them for viral illnesses like the common cold is not only useless, but can also unnecessarily expose the body to side effects.