Only 5 Questions with Nutritionist Christy Harrison
What are some healthy ways to encourage the growth of good gut bacteria?
To encourage the growth of good gut bacteria, eat plenty of fiber from vegetables, fruits, and whole grains, and moderate amounts of protein and fat. The gut microbiota of people with plant-centric diets look very different from the microbiota of those who eat a standard Western diet, and these microbial differences parallel differences in health outcomes. It’s probably no surprise that the Western diet is associated with higher rates of chronic diseases, while the plant-rich diets are associated with lower rates.
Is there such a thing as too much good gut bacteria?
It’s very unlikely that the beneficial bacteria in the gut will overpopulate, but it can occur in people who have damaged intestines, compromised immune systems, or a preexisting overgrowth of bacteria in the intestines. If bacteria (beneficial or otherwise) is not regularly moved out of the small intestine, as it should be in normal digestion, then a condition known as small intestinal bacterial overgrowth (SIBO) can occur and cause uncomfortable GI symptoms. Usually the majority of gut bacteria reside in the large intestine (aka the colon).
What are some of the indications that we may have an imbalanced microflora?
[Indications] are all so nebulous, and the research is so young, that I wouldn't want to give people a cause for self-diagnosis at this point. But here are some symptoms of SIBO, and people can be tested for that: excessive gas, extreme bloating and abdominal distention, diarrhea, and abdominal pain. Constipation is a less likely symptom. [Consider your diet]
Does aging impact our microbiome? And are there specific kinds of exposures that can adversely affect our microbiome?
There is some evidence that aging adversely affects the microbiome. Exposure to antibiotics, high-fat and low-fiber diets, and excessive alcohol use can all have a negative impact on the health of the microbiome.
In recent studies, our gastrointestinal system has been suggests as the home to our "second brain" -- can you expand on that concept a little bit?
This is really oversimplified, but the gut has a system of neurons, hormones, and chemicals that function both independently of the brain and in communication with it. The gut is able to transmit information to the brain about the intestinal environment—for example, the rate at which food is being digested—and the microbes are an integral part of that environment.
Christy Harrison, MPH, RD, CDN is a registered dietitian nutritionist in private practice, specializing in NUTRITIONtherapy for eating disorders, chronic disease prevention and management, and wellness. Using principles of intuitive eating and mindfulness, she helps people improve their relationships to food while improving their health.
Christy is also a journalist with more than 12 years of experience in food and nutrition media. She has written for and edited award-winning books, magazines, and websites, including Gourmet and Modernist Cuisine, and she offers career coaching to help others improve their writing and social media skills. Her work aims to capture the joy in food and the nuances of nutrition science and food politics.