By now we’re all familiar with the fact that gut health matters — a lot. After all, microbes in the gut have been linked to a whole host of health conditions, from small intestinal bacterial overgrowth (SIBO) to altered blood sugar regulation, depression, and colorectal cancer.
Chances are you already take a daily probiotic supplement, or opt for eats like Lavva Yogurt and kimchi for a hit of beneficial bacteria. But probiotic-rich foods aren’t the only ones that make our microbiome happy.
Enter: resistant starches.
What is resistant starch?
Resistant starches are exactly what they sound like: carbohydrates that are resistant to digestion in the GI tract. You can think of them as a counterpart to dietary fiber. Instead of getting digested and absorbed in the small intestine, resistant starches, which act as prebiotics, are fermented by bacteria in the colon. This fermentation process triggers the production of compounds called short-chain fatty acids (SCFAs), plus some gas.
Health benefits of resistant starches
The SCFAs produced by the fermentation of resistant starches serve as an important source of fuel for gut microbes and cells of the large intestine. By feeding the good gut bugs (think: Lactobacilli and Bifidobacteria), resistant starches and their associated SCFAs fortify the beneficial bacteria and crowd out the bad bacteria.
What’s more, SCFAs like propionate and butyrate encourage the colon cells to grow and turn over, which may help reduce one’s risk of colorectal cancer.
All backed up? Resistant starches can help with that. The non-digestible carbs can increase the weight of our stool and in turn encourage GI motility. In other words, they keep things moving right along.
Since resistant starches aren’t metabolized to glucose and absorbed, they don’t raise our blood sugar levels like other carbs do. That may be why some studies suggest that resistant starches can help improve insulin sensitivity and lower fasting blood sugar levels.
The non-digestible carbs might also reduce the “bad” LDL cholesterol in our blood. That’s not all that surprising since sources of resistant starch include heart healthy plant foods. More on that below.
Sources of resistant starch
Good news: resistant starches aren’t all that hard to come by. Here are few sources of resistant starches:
- Plantains* & greenish bananas – As bananas ripen, the resistant starch gets converted to regular starch and loses its prebiotic benefits. *Fun fact: Lavva includes young plantains rich in resistant starch in our plant-based yogurts, which also serve up probiotic cultures. Talk about a double win.
- Legumes, like white beans and lentils – dry legumes can be 20-30% resistant starch by weight, per Harvard’s T.H. Chan School of Public Health
- Jerusalem artichokes (AKA sunchokes)
- Cooked, then cooled carbohydrates. Cooking and then cooling carbs like potatoes, rice, and pasta in the fridge overnight recrystallizes the starch molecules in the food, which in turn strengthens their resistant starch qualities. Research shows that heating up the cooled, cooked carbs doesn’t reduce their resistant starch content, so feel free to reheat last night’s noodles or enjoy them cold in a summery pasta salad.
The bottom line on resistant starch
Clearly, eating resistant starches is a good idea for your gut. But the fiber-like carbs are also tied to broader health benefits, like blood sugar regulation and increased satiety. Aim to include resistant starches in your daily diet with Lavva Yogurt for breakfast, legumes in your lunch salad, and a cold sweet potato salad with dinner. Thank us later.
Written by Anthea Levi, MS, RD