Replacing carb snacks with pistachios before bed may boost gut bacteria linked to reduced inflammation, according to a new study.
Study on prediabetes and pistachios
A study conducted on adults with prediabetes suggests that replacing a carbohydrate-rich snack with pistachios before bedtime could promote certain beneficial intestinal bacteria. Researchers from Pennsylvania State University tested this change on 51 adults with prediabetes over twelve weeks.Trial design and results
In a randomized crossover trial published in July 2025 in the journal Current Developments in Nutrition, participants were asked to replace their snack containing 15 to 30 grams of carbohydrates with about 57 grams of pistachios in the evening. The analysis showed an increase in bacteria such as Roseburia and the Lachnospiraceae family, which produce short-chain fatty acids (SCFAs), an interesting lead for inflammation management.Trial completion and microbial changes
According to the publication from Pennsylvania State University, 51 of the 66 volunteers completed the two 12-week periods. Each person tested the carbohydrate snack and then the pistachios, always in the evening. This type of randomized trial limits the effect of individual differences. The authors describe a shift in the intestinal microbial landscape with more bacteria producing butyrate, a short-chain fatty acid (SCFA) crucial for the intestinal mucosa.Nutritionist comments on pistachios
For nutritionist Federica Amati, from ZOE, pistachios have a very interesting profile.
