What about blended beans like hummus? Unlike grains, blending legumes doesn't affect their glycemic response.

My general take on beans is simple: the more beans, the better — however you get them.

Another way to feed our good bacteria is to eat intact grains, beans, nuts, and seeds.

In one study, researchers split people into two groups and had them eat the same food, but in one group, the seeds, grains, beans, and chickpeas were eaten more or less in a whole form, while they were ground up for the other group. For example, for breakfast, the whole-grain group got muesli, and the ground-grain group had the same muesli, but it was blended into a porridge. Similarly, beans were added to salads for the whole-grain group, whereas they were blended into hummus for the ground-grain group.

Note that both groups were eating whole grains—not refined—that is, they were eating whole foods. In the ground-grain group, though, those whole grains, beans, and seeds were made into flour or blended up.

What happened? Those on the intact whole-grain diet “resulted in a doubling of the amount excreted compared to the usual diet and produced an additional and statistically significant increase in stool mass” compared with those on the ground whole-grain diet, even though they were eating the same food and the same amount of food. Why?

On the whole-grain diet, there was so much more for our good bacteria to eat that they grew so well and appeared to bulk up the stool. Even though people chewed their food, “[l]arge amounts of apparently whole seeds were recovered from stools,” but on closer inspection, they weren’t whole at all. Our bacteria were having a smorgasbord. The little bits and pieces left after chewing transport all this wonderful starch straight down to our good bacteria. As a result, stool pH dropped as our bacteria were able to churn out so many of those short-chain fatty acids. Whole grains are great, but intact whole grains may be even better, allowing us to feed our good gut bacteria with the leftovers.