Researchers find that a healthy gut may make the difference between aging poorly and aging well.

How’s your gut these days?

It’s a simple question, but some researchers believe the answer may one day help physicians predict your health in old age.

In a new study published in mSphere by the American Society for Microbiology, Chinese researchers collected and analyzed the gut microbiota of more than 1,000 healthy Chinese people.

Study participants were all between 3 years old and over 100 years old.

Gut microbiota was collected from each participant and analyzed using 16S rRNA gene sequencing along with various measuring techniques.

Researchers found that from age 30 upward, the microbiota of older subjects is similar to those who are oftentimes decades younger.

The results suggest to researchers that by resetting an older person’s unhealthy gut microbiota to the healthier levels of, for example, a 30-year-old, science may one day be able to positively influence one’s future health.

Healthline spoke with Dr. Rudolph Bedford, gastroenterologist at Providence Saint John’s Health Center in California, about the study.

Bedford said, “The indigenous microbiota environment, it’s kind of changed our whole idea of human health and disease. Probably the most radical change is that we now realize that most of the microbiota that are in our blood supply are crucial to our own bodies’ ecosystem. So they kind of benefit the entire host, which is us, the human body, in a variety of ways.”

Bedford responded to the claim that someday scientists will be able to predict future health from gut microbiota.

“Yes, that’s exactly what, reading that article, that’s exactly what they’re predicting,” he said.

“And in the future, “ continued Bedford, “the ability to study the gut microbiota will help to define potential disease states that one might be able to intervene and prevent. And [this will] also give you an idea as to whether or not you can change the gut microbiota in a variety of ways with our own probiotics, so to speak.

“The [gut] bacteria themselves, they do a lot of things,” said Bedford. “They protect us against various pathogens or microbes or things of that sort. They help to convert our foods into energy packets. They essentially are a real necessity in terms of human health and growth as we get older.”

Bedford continued, “They [gut microbiota] protect us from various diseases, certainly help us digest our foods, and act as a guardian of the body to prevent various bacteria from invading our bodies in a variety of ways.”

Asked whether he subscribes to the theory that science will one day be able to influence our future health by changing the microbiota in our gut, Bedford said, “Well, right now we certainly are handing out a lot of probiotics.

“I’ll give you an example,” continued Bedford. “There is an infection that has become very prevalent. It’s called Clostridium difficile. It’s associated with antibiotic use, unfortunately. So we’re using a lot of probiotics to help prevent recurrence of Clostridium difficile.”

Which, in effect, affects that person’s future health.

Asked about the study itself, Bedford said, “It’s certainly an interesting, far-reaching study in that they’re looking at large populations and how the bacteria levels change as we age which, quite frankly, makes sense because as we age we’re now exposed to a variety of things in terms of the foods we eat, the medications we take, the antibiotics that we’re given.

“And all of these things will change the bacterial levels within the small intestine. And the healthier the bacterial levels are, the less likely you are of developing various diseases, and you’ll likely live longer.” continued Bedford.

Dr. Ashkan Farhadi, gastroenterologist at MemorialCare Orange Coast Medical Center and director of MemorialCare Medical Group’s Digestive Disease Project in California, isn’t so sure about using microbiota to predict future health.

“Our current knowledge of microbiota of the gut is in its infancy,” Farhadi said.

“We’re talking about one-million species [inside each person], each one [is] doing something completely different from the others,” said Farhadi. “And that’s what is so dynamic.”

The fact that the microbiota composition constantly changes as we eat different foods, when we get sick, have an infection, or even use an antibiotic, makes it difficult to see trends.

“We have shown that, for example, when we are going through some sort of flare of ulcerative colitis or other disease, the bacterial population is statistically different from other groups,” said Farhadi. “But we not dare use this diagnostic or prognostic tool at this point. We are saying, ‘Look, we are seeing some trends.’ And that is true. We are seeing some trends. But we are far from using those trends toward any diagnostic, prognostic, or therapeutic intervention.

“Even our knowledge of probiotics [which we do use] is really crude,” said Farhadi.

“First of all, I’m a big fan of probiotics,” said Farhadi. “I’m using it day in and day out. And what I always tell my patients is, again, our knowledge of how this [probiotic] works is really crude.

“We know, in many diseases that I personally treat, irritable bowel syndrome, ulcerative colitis, many GI ailments, we know probiotics helps to a great deal in many of those conditions,” said Farhadi. “It doesn’t work for everyone, but it works in a big group of people.”

Both Farhadi and Bedford sound a singular note of caution about choosing a probiotic.

“Number one, I wish they were regulated by the FDA,” said Bedford. “That’s the problem, they’re not. So that’s number one, because if they were at least regulated in that way — I think they’re categorized as almost a food supplement in some respects — and that’s probably the reason. So people can write anything they want to on the box and sell it as a probiotic.

“There are probiotics that physicians prescribe that are in pharmacies that are real and that do contain billions of good bacteria. Those are the ones that [I would take] and have my physician actually recommend, as opposed to going to the store and just taking what’s on the shelf,” continued Bedford.

As we age, our bodies change.

But since we didn’t come with an owner’s manual, it helps to know which changes might actually be sending us warnings.

When it comes to changes in the gut that might suggest a trip to the doctor, Bedford said, “Gassiness, bloating is usually the first symptom that people will experience. With that gassiness may come diarrhea. Those are the two most notable symptoms that people will have.

“There’s this unfortunate term that’s been thrown out there all over the place in lay literature called ‘leaky gut syndrome.’ I don’t know what the heck leaky gut syndrome actually is, but the proposition is that the gut is somehow leaking toxins that the bacteria would normally metabolize. Again, it’s bloating and diarrhea are the first two signs that there may be some issues with the bacterial levels within the small intestine.”

Farhadi looks for changes. “Two things I can mention without question. First of all, I always believe that any change, any change that is different from your routine, from your typical bowel habits.”

These would be changes that do not disappear after a day or two.

“For example, your bowel habit used to be every other day. Now it’s every four days for the last two months. That should raise some concern,” said Farhadi.

Farhadi stressed that everyone needs to be vigilant when it comes to the worst of all gastrointestinal ailments… colon cancer.

“Six percent of the population is eventually going to be having colon cancer,” stressed Farhadi. “And typically [colon cancer] does not present with any symptoms till it’s too late. So my suggestion is that if you’re over 50, go get your screening done, one way or another, because there’s no alarm.

“If you have your alarm sign, then the horse is out of the barn. That’s my suggestion,” said Farhadi.

Not all studies are created equal, and when asked what he thinks about the study in question, Farhadi said simply, “What I see is not exactly what they are trying to say in the figures.

“I see a good difference in the population according to their age, even the categories that they show in the figures. And that’s completely expected. I think that they could not show that there is a big difference, statistically, between these [age] groups that they are showing. But in medicine, when we cannot find a difference, we don’t say that they’re the same. We don’t claim that. We say we couldn’t show the difference.”

However, Farhadi also pointed to what he sees as a positive.

“There are a lot of interesting findings in this study, and there are some flaws,” said Farhadi. “But if we want to focus on positive things that the study shows, it’s that when we’re checking the bacterial diversity in the intestine, in the fecal material, in a wide range of population in China, we’re getting kind of closer association compared to other places.”

Since the study was performed strictly on healthy Chinese individuals chosen from specific subgroupings, such as soldiers and police, can we infer that the results would be the same if performed on a more diverse population here in the United States?

“The answer is a difficult one because, obviously, our foods and processes are different from theirs, as it would be in any other country,” said Bedford. He suggested that here in the United States, “we’d have to do our own similar study and see whether or not it actually pans out.”