New research using roundworms and mice has shown that one probiotic of human origin does not have to be alive to reduce markers of inflammation and promote health.

Share on Pinterest Even when inactivated, a strain of Lactobacillus paracasei could reduce inflammation and boost health, a new study suggests.

Probiotics are usually live, active bacteria that interact with the gut flora — the bacteria already present in the gut.

Nutritionists and other health specialists have found that probiotics can offer many health benefits when people ingest them in the right amounts. These benefits include rebalancing the population of bacteria in the gut, aiding digestion, and improving symptoms of gastrointestinal conditions, such as irritable bowel syndrome.

Increasingly, research is showing that inactivated — or “dead” — probiotic bacteria may also offer a host of benefits. Yet, since the definition of probiotics refers to “live microorganisms,” many scientists argue that “dead” or inactivated bacteria do not qualify as probiotics, and some propose a different name for them: paraprobiotics.

Some specialists also argue that while medical authorities regulate probiotics as dietary supplements, inactivated probiotic bacteria would fit more under the class of drugs, and they should be regulated as such.

Be that as it may, the notion that some probiotic bacteria may be effective, even once inactivated, has stirred the interest of researchers ever looking for ways of improving people’s well-being.

Now, a new study from the Wake Forest School of Medicine in Winston-Salem, NC has tested the potential for health of an inactivated strain of human-derived Lactobacillus paracasei (D3-5).

In the study paper — which appears in the journal GeroScience — the authors report finding that, even after inactivation, L. paracasei demonstrated effectiveness by extending lifespan in roundworm experiments, and it also reduced inflammation and improved cognitive function in elderly mice.