Researchers in two different studies examine ways to reduce the cognitive decline in people who have Alzheimer’s disease.

Alzheimer’s is a devastating and ultimately fatal disease, but there may be a new form of treatment on the horizon.

In a new clinical trial, researchers say they’ve successfully used probiotics to slow down cognitive impairment in Alzheimer’s patients.

Probiotics are the beneficial microorganisms that many people take as dietary supplements.

Doctors from Kashan University of Medical Sciences in Iran conducted a randomized, double-blind controlled clinical trial in which women and men between 60 and 95 years of age were given a daily dose of milk enriched with four probiotic bacteria.

A control group was given milk without probiotic bacteria.

By the end of the 12-week experimental study, patients who had been given probiotics saw improved scores on the Mini-Mental State Examination scale, a metric for measuring cognitive improvement.

“In a previous study, we showed that probiotic treatment improved the impaired spatial learning and memory in diabetic rats, but this is the first time that probiotic supplementation has been shown to benefit cognition in cognitively impaired humans,” said senior author Professor Mahmoud Salami in a press release.

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There are medicines for Alzheimer’s now, but their effectiveness is limited.

“There are five currently approved medications in the United States and typically they fall into a couple of different categories, but the most important thing to know about them is that they’re really not adequate to the task at hand,” Keith Fargo, Ph.D., Director of Scientific Programs and Outreach for the Alzheimer’s Association, told Healthline.

“Alzheimer’s disease is a universally fatal brain disease. The medications that are currently approved for use in Alzheimer’s disease do not appear to slow down the process of what’s happening in the brain for a person who has Alzheimer’s disease,” Fargo added. “You have amyloid plaques that build up, you have tau tangles that build up, you have the loss of synapses and brain cells that continues unabated with the current medications.”

Because of this, Fargo says, doctors and researchers are constantly examining new approaches for treating the disease.

“A couple of interesting things that come to mind that people have looked at recently are therapies that are aimed at busting the amyloid plaques,” he noted.

One of these is an amyloid-lowering drug, verubecestat, which has entered phase III testing.

This compound blocks the enzyme BACE1, which is a major contributor to Alzheimer’s. It also reduced the levels of toxic β-amyloid, which clumps into plaques and damages the brain of people with Alzheimer’s disease.

Among 32 study participants, verubecestat showed positive results with limited side effects.

Lifestyle factors may also play a role in the onset of Alzheimer’s disease.

“There’s a large exercise study that’s getting ready to launch called the Exert trial,” says Fargo. “There seems to be fairly good evidence that exercise and physical activity may be able to at least delay the onset of some of the dementia symptoms that people experience when they have Alzheimer’s disease.”

“The good news is that people are actually pursuing a wide array of avenues in research for Alzheimer’s disease, and that’s a welcome development,” he added.

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While progress is being made in the field of Alzheimer’s research, it’s important to measure expectations.

Positive results from a study or trial are one thing, but any potential treatments need to clear the significant hurdle of Food and Drug Administration (FDA) approval.

Fargo says the probiotic trial from Kashan University was designed and executed well — but researchers still have a way to go.

“This is how you want to design a study to examine the safety and effectiveness of something like probiotics, but in order to really know if it’s safe and effective, you have to do it in much larger groups of people,” he said. “For example, the FDA would generally require something more along the lines of several thousand people in a study like this.”

It’s also important for patients and doctors to be aware of possible risks, even when it comes to seemingly benign substances like probiotics.

“There may be a tendency to say, ‘Oh, it’s probiotics, people take these all the time, it’s harmless, so we might as well try it.’ I think that’s an oversimplification,” says Fargo.

“I think the tendency to jump to the conclusion, based on a small clinical trial like this, is that this is something that people should begin using or that doctors ought to begin prescribing this to their patients,” he added.

“But the viewpoint of the Alzheimer’s Association is that the science is just not far enough along for that and you really need larger clinical trials to show that,” he explained. “So at this point, people should make sure that they’re talking to their doctors about anything that they take, including supplements, probiotics, vitamins, et cetera. The Alzheimer’s Association is always happy to see new ways of thinking about treating the disease, but we have to be conservative in terms of what we recommend to people.”

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