Probiotics are not new, but their status as a nutritional buzzword is. Most folks have now heard and seen the term countless times in commercials and advertisements, as yogurt, dietary supplement, natural food product, and even cosmetic companies promote their probiotic-containing products.
But what are they, and why are they important? Probiotics are live bacteria that help maintain a healthy digestive system. The development and marketing of products that contain live bacteria has flourished as there is a growing perceived interest in the ingestion of 'natural foods' that might promote health.
Many of the numerous health-improvement claims have yet to be supported scientifically, but these micro-organisms do exert positive effects in intestinal tracts, particularly when used to counteract the effects of antibiotics, which kill both 'bad' and 'good' bacteria. Indeed, the first known description of probiotics occurred in 1908 when a Russian scientist named Élie Metchnikoff observed that rural Europeans who regularly consumed fermented milk product had longer life spans.
Over the past few years, studies have been undertaken to explore the possible impact of probiotics on behavior. It is within this context that the concept of a psychobiotic has arisen.
The authors of a new review article in Biological Psychiatry, Timothy Dinan and his colleagues from University College Cork in Ireland, define a psychobiotic as "a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness."
They review the evidence that these bacteria, when ingested in adequate amounts, offer enormous potential for the treatment of depression and other stress-related disorders.
The gut microbiota, which contains approximately 1 kg of bacteria, can be modulated by diet and many other factors. It is not static and can change from day to day, starting at birth. Evidence has shown that even the form of delivery (vaginal versus cesarean) alters an individual's microbiota.
Early life stress, such as maternal separation, is known to induce long-term changes in the microbiome. Dinan and his colleagues review one study that assessed the potential benefits of a specific probiotic, B. infantis, in rats displaying depressive behavior due to maternal separation. The probiotic treatment normalized both their behavior and their previously-abnormal immune response. This preclinical study and others like it strongly support the hypothesis that probiotics have the potential to exert behavioral and immunological effects.
Some psychobiotics have been shown to have anti-inflammatory effects. This is important because depression and stress are both associated with inflammation in the body. Infectious diseases, such as syphilis and Lyme disease, can also produce depressive states. Evidence suggests that immune activations, perhaps via psychobiotic action, could alleviate such states. According to the authors, "the intestinal microbial balance may alter the regulation of inflammatory responses and in so doing, may be involved in the modulation of mood and behavior."
Human studies are still largely lacking, but a few have shown promising results. In one, healthy volunteers received either a probiotic combination (L.. helveticus R0052 and B. longum) or placebo for 30 days. Those who received the probiotics reported lower stress levels. In a separate study, volunteers who consumed a yogurt containing probiotics reported improved mood.
"What is clear at this point is that, of the large number of putative probiotics, only a small percentage have an impact on behaviour and may qualify as psychobiotics," said Dinan.
"This intriguing new area of research may open new possibilities for the treatment of depression," said Dr. John Krystal, Editor of Biological Psychiatry.
For now, we must all wait for scientists to conduct large-scale, placebo-controlled trials to provide definitive evidence.
Explore further: Can probiotics keep gastrointestinal system healthy?
More information: "Psychobiotics: A Novel Class of Psychotropic" by Timothy G. Dinan, Catherine Stanton, and John F. Cryan (DOI: 10.1016/j.biopsych.2013.05.001). The article appears in Biological Psychiatry, Volume 74, Issue 10 (November 15, 2013)
Medical Xpress on facebook
Related Stories
Can probiotics keep gastrointestinal system healthy?
Sep 17, 2013
There's convincing evidence that probiotics can be helpful in maintaining gastrointestinal health in certain situations. But like many natural approaches to maintaining health, there's been a tendency toward ...
Researchers call for new rules to regulate probiotics
Oct 17, 2013
The U.S. Food and Drug Administration (FDA) should consider the unique features of probiotics—bacteria that help maintain the natural balance of organisms in the intestines—in regulating their use and marketing, says ...
Probiotics prevent diarrhoea related to antibiotic use
May 30, 2013
Probiotic supplements have the potential to prevent diarrhoea caused by antibiotics, according to a new Cochrane systematic review. The authors studied Clostridium difficile (C. difficile) infections in patients taking antibi ...
What else may probiotics do in adults?
May 20, 2008
Probiotic bacteria, defined as living microorganisms that have beneficial effects on human health, have mostly been studied in the prevention and treatment of different gastrointestinal diseases and allergies. Probiotic products, ...
Study: Probiotics reduce stress-induced intestinal flare-ups
Mar 14, 2013
For those with irritable bowel syndrome who wonder if stress aggravates their intestinal disorder, a new University of Michigan Health System study shows it's not all in their head.
Recommended for you
Literacy depends on nurture, not nature, education professor says
37 seconds ago
A University at Buffalo education professor has sided with the environment in the timeless "nurture vs. nature" debate after his research found that a child's ability to read depends mostly on where that child is born, rather ...
Putting it off: Why we procrastinate
30 minutes ago
Everyone procrastinates. I became somewhat distracted by completely irrelevant websites, for instance, while preparing to write this article.
Cognitive scientists ID new mechanism at heart of early childhood learning and social behavior
15 hours ago
Shifting the emphasis from gaze to hand, a study by Indiana University cognitive scientists provides compelling evidence for a new and possibly dominant way for social partners—in this case, 1-year-olds ...
Wireless sensors used to study meditation's effect on heart health
18 hours ago
Demystifying meditation with science, researchers at the Scripps Translational Science Institute (STSI) have teamed with The Chopra Foundation and The Chopra Center for Wellbeing in a novel study of the ancient ...
Back to the future: Nostalgia increases optimism
21 hours ago
New research from the University of Southampton shows that feeling nostalgic about the past will increase optimism about the future.
Study finds context is key in helping us to recognize a face
Nov 13, 2013
Why does it take longer to recognise a familiar face when seen in an unfamiliar setting, like seeing a work colleague when on holiday? A new study published today in Nature Communications has found that part of the reason ...
User comments
© Medical Xpress 2011-2013, Phys.org network
Probiotics are not new, but their status as a nutritional buzzword is. Most folks have now heard and seen the term countless times in commercials and advertisements, as yogurt, dietary supplement, natural food product, and even cosmetic companies promote their probiotic-containing products.
But what are they, and why are they important? Probiotics are live bacteria that help maintain a healthy digestive system. The development and marketing of products that contain live bacteria has flourished as there is a growing perceived interest in the ingestion of 'natural foods' that might promote health.
Many of the numerous health-improvement claims have yet to be supported scientifically, but these micro-organisms do exert positive effects in intestinal tracts, particularly when used to counteract the effects of antibiotics, which kill both 'bad' and 'good' bacteria. Indeed, the first known description of probiotics occurred in 1908 when a Russian scientist named Élie Metchnikoff observed that rural Europeans who regularly consumed fermented milk product had longer life spans.
Over the past few years, studies have been undertaken to explore the possible impact of probiotics on behavior. It is within this context that the concept of a psychobiotic has arisen.
The authors of a new review article in Biological Psychiatry, Timothy Dinan and his colleagues from University College Cork in Ireland, define a psychobiotic as "a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness."
They review the evidence that these bacteria, when ingested in adequate amounts, offer enormous potential for the treatment of depression and other stress-related disorders.
The gut microbiota, which contains approximately 1 kg of bacteria, can be modulated by diet and many other factors. It is not static and can change from day to day, starting at birth. Evidence has shown that even the form of delivery (vaginal versus cesarean) alters an individual's microbiota.
Early life stress, such as maternal separation, is known to induce long-term changes in the microbiome. Dinan and his colleagues review one study that assessed the potential benefits of a specific probiotic, B. infantis, in rats displaying depressive behavior due to maternal separation. The probiotic treatment normalized both their behavior and their previously-abnormal immune response. This preclinical study and others like it strongly support the hypothesis that probiotics have the potential to exert behavioral and immunological effects.
Some psychobiotics have been shown to have anti-inflammatory effects. This is important because depression and stress are both associated with inflammation in the body. Infectious diseases, such as syphilis and Lyme disease, can also produce depressive states. Evidence suggests that immune activations, perhaps via psychobiotic action, could alleviate such states. According to the authors, "the intestinal microbial balance may alter the regulation of inflammatory responses and in so doing, may be involved in the modulation of mood and behavior."
Human studies are still largely lacking, but a few have shown promising results. In one, healthy volunteers received either a probiotic combination (L.. helveticus R0052 and B. longum) or placebo for 30 days. Those who received the probiotics reported lower stress levels. In a separate study, volunteers who consumed a yogurt containing probiotics reported improved mood.
"What is clear at this point is that, of the large number of putative probiotics, only a small percentage have an impact on behaviour and may qualify as psychobiotics," said Dinan.
"This intriguing new area of research may open new possibilities for the treatment of depression," said Dr. John Krystal, Editor of Biological Psychiatry.
For now, we must all wait for scientists to conduct large-scale, placebo-controlled trials to provide definitive evidence.
Explore further: Can probiotics keep gastrointestinal system healthy?
More information: "Psychobiotics: A Novel Class of Psychotropic" by Timothy G. Dinan, Catherine Stanton, and John F. Cryan (DOI: 10.1016/j.biopsych.2013.05.001). The article appears in Biological Psychiatry, Volume 74, Issue 10 (November 15, 2013)
Medical Xpress on facebook
Related Stories
Can probiotics keep gastrointestinal system healthy?
Sep 17, 2013
There's convincing evidence that probiotics can be helpful in maintaining gastrointestinal health in certain situations. But like many natural approaches to maintaining health, there's been a tendency toward ...
Researchers call for new rules to regulate probiotics
Oct 17, 2013
The U.S. Food and Drug Administration (FDA) should consider the unique features of probiotics—bacteria that help maintain the natural balance of organisms in the intestines—in regulating their use and marketing, says ...
Probiotics prevent diarrhoea related to antibiotic use
May 30, 2013
Probiotic supplements have the potential to prevent diarrhoea caused by antibiotics, according to a new Cochrane systematic review. The authors studied Clostridium difficile (C. difficile) infections in patients taking antibi ...
What else may probiotics do in adults?
May 20, 2008
Probiotic bacteria, defined as living microorganisms that have beneficial effects on human health, have mostly been studied in the prevention and treatment of different gastrointestinal diseases and allergies. Probiotic products, ...
Study: Probiotics reduce stress-induced intestinal flare-ups
Mar 14, 2013
For those with irritable bowel syndrome who wonder if stress aggravates their intestinal disorder, a new University of Michigan Health System study shows it's not all in their head.
Recommended for you
Literacy depends on nurture, not nature, education professor says
37 seconds ago
A University at Buffalo education professor has sided with the environment in the timeless "nurture vs. nature" debate after his research found that a child's ability to read depends mostly on where that child is born, rather ...
Putting it off: Why we procrastinate
30 minutes ago
Everyone procrastinates. I became somewhat distracted by completely irrelevant websites, for instance, while preparing to write this article.
Cognitive scientists ID new mechanism at heart of early childhood learning and social behavior
15 hours ago
Shifting the emphasis from gaze to hand, a study by Indiana University cognitive scientists provides compelling evidence for a new and possibly dominant way for social partners—in this case, 1-year-olds ...
Wireless sensors used to study meditation's effect on heart health
18 hours ago
Demystifying meditation with science, researchers at the Scripps Translational Science Institute (STSI) have teamed with The Chopra Foundation and The Chopra Center for Wellbeing in a novel study of the ancient ...
Back to the future: Nostalgia increases optimism
21 hours ago
New research from the University of Southampton shows that feeling nostalgic about the past will increase optimism about the future.
Study finds context is key in helping us to recognize a face
Nov 13, 2013
Why does it take longer to recognise a familiar face when seen in an unfamiliar setting, like seeing a work colleague when on holiday? A new study published today in Nature Communications has found that part of the reason ...
User comments
© Medical Xpress 2011-2013, Phys.org network
0 comments:
Post a Comment