More and more research is being done on the gut microbiome, the community of bacteria and fungi found in your digestive tract. These microbes out number our human cells 10 to 1 and can contribute up to 5 lbs of one’s overall weight. These little organisms partake in digestion, nutrient absorption, immune function, neurotransmitter production, and more. In fact, recent research suggests differences in the microbiome of lean individuals compared to their overweight peers.

Two of the major bacterial phyla in the human gut are Bacteroidetes and Firmicutes. In the healthy human gut, Bacteroidetes should make up the majority of the gut bacterial community. However, in a number of studies, those who are overweight show a higher proportion of Firmicutes in their gut. Firmicutes has been shown to increase energy absorption, which means that if Suzy has more Bacteroidetes and Stan has more Firmicutes, if they both eat the same meal, Suzy will absorb LESS calories from that meal than Stan. In other words, this creates a pretty vicious cycle! Over-eating/excess energy intake encourage Firmicutes growth; Firmicutes increases calorie absorption, leading to further weight gain, and the cycle continues!

So, what can you do? To optimize your gut health, one of the most important things you can do for an immediate response is to eat more fiber from plant foods throughout your day. A good goal would be to eat 9 servings or cups every day of a variety of whole fruits, vegetables, and leafy greens. This can be a challenge since most of us eat maybe a third of this, but you will see the benefits right away. The fiber in these foods feed “good” gut flora and for some people, a change can be seen within 24 hours. Over the long-term, the nutrient density and fiber in these foods will be a significant factor to help your body decrease inflammation, increase Bacteroidetes, and reduce Firmicutes.  Additionally, regular, consistent exercise has been found to support proper gut balance. While formal exercise (examples: walking, cardio classes, weight training) is a great choice, other increases in your daily activity level (examples: gardening, taking the stairs at work) can make a positive impact.

Finally, remove any artificially sweetened foods and beverages from your diet. Look for these words on the food label and always avoid the foods or beverages that contain:    Aspartame (Equal, NutraSweet, NatraTaste Blue), Sucralose (Splenda), Acesulfame Potassium or K (ACE K, Sunette, Equal Spoonful, Sweet One, Sweet ‘n Safe), and Saccharin (Sweet ‘N Low, Sweet Twin). If you’ve been relying on artificial sweeteners, please work to remove them from your diet and instead opt for whole fruits when you’re craving sweetness. While sugar is definitely something to reduce and avoid in your diet, artificial sweeteners have been shown to radically disrupt the microbiome and increase phyla related to inflammation.

You are what you eat, and what you eat, is what your gut bacteria and fungi consume! So do yourself a favor, and feed them well.

Aubrey Phelps MS RDN LDN