hilary1617
First time at the rodeo.
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http://www.theatlantic.com/health/archive/2015/06/gut-bacteria-on-the-brain/395918/?utm_source=SFFB
“This was not what we expected, that eating yogurt twice a day for a few weeks would do something to your brain.”
By now, the idea that gut bacteria affects a person’s health is not revolutionary. Many people know that these microbes influence digestion, allergies, and metabolism. The trend has become almost commonplace: New books appear regularly detailing precisely which diet will lead to optimum bacterial health.
But these microbes’ reach may extend much further, into the human brains. A growing group of researchers around the world are investigating how the microbiome, as this bacterial ecosystem is known, regulates how people think and feel. Scientists have found evidence that this assemblage—about a thousand different species of bacteria, trillions of cells that together weigh between one and three pounds—could play a crucial role in autism, anxiety, depression, and other disorders.
....
Other research has examined entire humans, not just their bugs. A paper published in the May 2015 issue of Psychopharmacology by the Oxford University neurobiologist Phil Burnet looked at whether a prebiotic—a group of carbohydrates that provide sustenance for gut bacteria—affected stress levels among a group of 45 healthy volunteers. Some subjects were fed 5.5 grams of a powdered carbohydrate known as galactooligosaccharide, or GOS, while others were given a placebo. Previous studies in mice by the same scientists had shown that this carb fostered growth of Lactobacillus and Bifidobacteria; the mice with more of these microbes also had increased levels of several neurotransmitters that affect anxiety, including one called brain-derived neurotrophic factor.
Perhaps the most well-known human study was done by Mayer, the UCLA researcher. He recruited 25 subjects, all healthy women; for four weeks, 12 of them ate a cup of commercially available yogurt twice a day, while the rest didn’t. Yogurt is a probiotic, meaning it contains live bacteria, in this case strains of four species, bifidobacterium, streptococcus, lactococcus, and lactobacillus. Before and after the study, subjects were given brain scans to gauge their response to a series of images of facial expressions—happiness, sadness, anger, and so on.
To Mayer’s surprise, the results, which were published in 2013 in the journal Gastroenterology, showed significant differences between the two groups; the yogurt eaters reacted more calmly to the images than the control group. “The contrast was clear,” says Mayer. “This was not what we expected, that eating a yogurt twice a day for a few weeks would do something to your brain.” He thinks the bacteria in the yogurt changed the makeup of the subjects’ gut microbes, and that this led to the production of compounds that modified brain chemistry.
“This was not what we expected, that eating yogurt twice a day for a few weeks would do something to your brain.”
By now, the idea that gut bacteria affects a person’s health is not revolutionary. Many people know that these microbes influence digestion, allergies, and metabolism. The trend has become almost commonplace: New books appear regularly detailing precisely which diet will lead to optimum bacterial health.
But these microbes’ reach may extend much further, into the human brains. A growing group of researchers around the world are investigating how the microbiome, as this bacterial ecosystem is known, regulates how people think and feel. Scientists have found evidence that this assemblage—about a thousand different species of bacteria, trillions of cells that together weigh between one and three pounds—could play a crucial role in autism, anxiety, depression, and other disorders.
....
Other research has examined entire humans, not just their bugs. A paper published in the May 2015 issue of Psychopharmacology by the Oxford University neurobiologist Phil Burnet looked at whether a prebiotic—a group of carbohydrates that provide sustenance for gut bacteria—affected stress levels among a group of 45 healthy volunteers. Some subjects were fed 5.5 grams of a powdered carbohydrate known as galactooligosaccharide, or GOS, while others were given a placebo. Previous studies in mice by the same scientists had shown that this carb fostered growth of Lactobacillus and Bifidobacteria; the mice with more of these microbes also had increased levels of several neurotransmitters that affect anxiety, including one called brain-derived neurotrophic factor.
Perhaps the most well-known human study was done by Mayer, the UCLA researcher. He recruited 25 subjects, all healthy women; for four weeks, 12 of them ate a cup of commercially available yogurt twice a day, while the rest didn’t. Yogurt is a probiotic, meaning it contains live bacteria, in this case strains of four species, bifidobacterium, streptococcus, lactococcus, and lactobacillus. Before and after the study, subjects were given brain scans to gauge their response to a series of images of facial expressions—happiness, sadness, anger, and so on.
To Mayer’s surprise, the results, which were published in 2013 in the journal Gastroenterology, showed significant differences between the two groups; the yogurt eaters reacted more calmly to the images than the control group. “The contrast was clear,” says Mayer. “This was not what we expected, that eating a yogurt twice a day for a few weeks would do something to your brain.” He thinks the bacteria in the yogurt changed the makeup of the subjects’ gut microbes, and that this led to the production of compounds that modified brain chemistry.
