Should Gut Bugs Influence the 2015 Dietary Guidelines?
As science and policy continue to collide, one thing remains certain: We are what we eat. This week, the National Institutes of Health hosted a public hearing about what should and shouldn't be included in the 2015 Dietary Guidelines for Americans -- a model template for healthful eating, one that's updated every five years.
What I hope policymakers take into account this year is basic biology, the science that tells us how our food choices impact everything from our physical and mental health to the types of bacteria that reside in our gut, which research continues to show is more important than we've ever known. New studies, including a review in this month's On the Cutting Edge, a publication of the Academy of Nutrition and Dietetics, show that the more diverse our gut flora is, the less likely we are to suffer from inflammation, Type 2 diabetes and obesity.
As we continue to learn more about the role bacteria play in the digestive process and how this ecosystem impacts overall health, we see that diversity is key and shaped largely by our diets. To create a rich microbiome, you should consider two major factors: prebiotics and probiotics (or fermentable and fermented foods). As the names somewhat imply, prebiotics serve as food for beneficial bacteria or probiotics.
Probiotics are live microorganisms, which remain metabolically active and fully intact once they reach the gastrointestinal tract. They balance pH levels in the colon, support healthy immune function, fend off pathogens (toxic intruders) and even make vitamins critical for health. To sustain these efforts, they feed off prebiotics, which flourish and ferment once they reach the microbiota.
Prebiotics help our bodies absorb essential minerals, reduce inflammation in the body, support insulin function, and suppress ghrelin, also known as the "hunger hormone." Together, probiotics and prebiotics are a powerhouse duo that team up to ensure our immune system, metabolism and intestinal tract are functioning at optimal speed.
While more research is needed to examine what comes first -- a diverse microbiota and flourishing health or vice versa -- we know it's best to stick to plant-based foods, adding fermented varieties to the mix. Here are my favorite easy-to-prepare sources:
Prebiotics:
Oats and whole grains
Asparagus
Onions and garlic
Bananas
Leafy Greens
Soybeans
Probiotics:
Water kefir
Tempeh
Kimchi (Korean spicy cabbage)
Sauerkraut (fermented cabbage)
Miso
Soy sauce
I hope to see the latest science continue to edge its way into the 2015 Dietary Guidelines for Americans. As both discussions forge ahead, what better time to merge the two? We're getting close to creating one, unified vision for health.
An apple a day, or in this case, a bowl of leafy greens, tempeh and kimchi, might just keep gut bugs growing and chronic disease at bay.
