EXPLORE THE WONDERS OF YOUR MICROBIOME
There is a strong link between your gut flora and your mood, which doctors are starting to figure out. Scientists have found potentially striking links between anxiety and depressions and gut bacteria, notes Martin Krigel, M.D. Ph. D., associate professor adjunct of immunobiology at the Yale School of Medicine. In one preliminary study, when anxious mice were given gut bacteria from mice who were not anxious, they experienced less anxiety as well as changes in their brain chemistry. In another small study, 40 people with depression were divided into two groups; at the end of eight weeks, the group given probiotics experienced a decrease in depression compared with the people who took a placebo.
Intestinal conditions like irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD), as well as symptoms like bloating and cramps, have been linked with an imbalance in the gut microbiome certain microbes produce a lot of gas and other chemicals linked to inflammation, which contribute to the symptoms of intestinal discomfort.
A healthy immune system
About 70 percent of your immune system lives in your gut these bacteria guard against pathogens and inflammation. And there's increasing evidence of links between your body's bacteria and autoimmune conditions like rheumatoid arthritis, multiple sclerosis and lupus, says Samatha Nazareth, M.D., a gastroenterologist in New York City. When there is a shift or imbalance in our gut bacteria or even the presence of a certain strain, in some cases the body thinks it's being invaded, which can trigger these disorders, says Dr. Kriegel.
People with a rich variety of gut bacteria were less likely to be obese, according to a study in the journal Nature. In animal studies, some mice transplanted with the microbiome from obese humans promptly gained weight, while the mice who received a thin person's microbiome stayed lean. It could be that the gut microbiome is able to influence weight through the bugs' ability to extract energy from food as well as their interaction with our appetite/satiety hormones and their role with the immune system, says Dr. Nazareth. On the upside, exercise seems to enhance gut bacteria.
One study found that certain gut microbiome characteristics were associated with "good" HDL cholesterol and triglycerides. And the bacteria lactobacilli found in fermented milk products may help reduce cholesterol.