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Our bodies play host to millions of bacteria. Actually, they outnumber our own cells by about 100-fold. And yet, we contain the notion that we’re responsible for our very own lives, not the bacteria that has just hitched a ride.
A new study, published in BioEssays, tells another story. The findings reveal that the bacteria within our bodies might actually be affecting our cravings and our moods to make sure that we eat what they want. The research team – from UC Bay area, Arizona State University and University of New Mexico – say these bacteria could be driving us to obesity.
The research team performed overview of recent scientific literature, finding that microbes influence human eating behavior and dietary choices, forcing a persons host to consume the particular nutrients they grow best on. Different species of bacteria need different nutrients. For example, some prefer fat, while others prefer sugar.
Dr. Athena Aktipis, PhD and co-founder from the Center for Evolution and Cancer with the Helen Diller Family Comprehensive Cancer Center at UCSF, states that bacteria not just need to compete with each other for food and to retain a distinct segment within their ecosystem – aka us – they likewise have different goals for the actions than we do.
The diverse ecosystem of bacteria inside our digestive system is famous collectively as the gut microbiome. Our decisions might be affected by signaling molecules released into our gut through the microbiome. Our gut is linked closely to the immune system, those hormones and also the central nervous system, making our physiologic and behavioral responses susceptible to influence from these signaling molecules.
“Bacteria within the gut are manipulative,” said Carlo Maley, PhD, director of the UCSF Center for Evolution and Cancer. “There’s a diversity of interests represented in the microbiome, some aligned with our own dietary goals, and others not.”
Maley shows that we’re not entirely without recourse. By deliberately choosing and altering what we consume, we are able to influence the compatibility from the gut microbiome, measurably changing it within 24 hours of diet change.
“Our diets have a big effect on microbial populations within the gut,” Maley said. “It’s an entire ecosystem, and it’s evolving on the time scale of minutes.” An example will be the bacteria based in the human gut biomes in Japan, in a position to digest seaweed since it is a popular choice in the diet.
The researchers think that the gut bacteria may be affecting our choices and behaviors by acting with the vagus nerve, which connects 100 million nerve cells in the digestive tract to the lower brain.
“Microbes have the capacity to manipulate behavior and mood through altering the neural signals within the vagus nerve, changing taste receptors, producing toxins to create us feel below par, and releasing chemical rewards to make us feel great,” said Aktipis, who is currently within the Arizona State University Department of Psychology.
The research team, including University of recent Mexico’s Department of Emergency Medicine’s Joe Alcock, MD, emphasizes that further scientific studies are essential to fully understand the amount of influence our gut bacteria might hold over us. For example, if bacteria that digest seaweed were transplanted in to the human gut, wouldn’t it lead the host to consume more seaweed?
For those trying to improve their health, the authors say there’s encouraging news in how quickly the microbiome could be changed. This transformation could be affected by food and supplement choices, probiotics and antibiotics. Creating an optimized balance of power among bacterial species within our gut may let us lead less obese and healthier lives, overall.
“Because microbiota are often manipulatable by prebiotics, probiotics, antibiotics, fecal transplants, and dietary changes, altering our microbiota offers a tractable method of otherwise intractable problems of obesity and unhealthy eating,” the authors wrote.
