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Products: Tree Nuts

Peanuts as a nighttime snack enrich butyrate-producing bacteria compared to an isocaloric lower-fat higher-carbohydrate snack in adults with elevated fasting glucose: A randomized crossover trial.

Authors: Sapp, P. A., Kris-Etherton, P. M., Arnesen, E. A., Chen See, J. R., Lamendella, R., & Petersen, K. S.
  • Journals: Clinical Nutrition
  • Pages: 2169–2177
  • Volume: 41(10)
  • Year: 2022
Background: Tree nuts have glucoregulatory effects and influence gut microbiota composition. The effect of peanuts on the microbiota has not been investigated. Objectives: The aim was to examine the effect of 28 g/d of peanuts for 6-wks, compared to an isocaloric lower-fat higher-carbohydrate (LFHC) snack, on gut microbiota composition. A secondary aim was to identify functional and active compositional differences in a subset of participants using metatranscriptomics. Methods: In a randomized, crossover trial, 50 adults (48% female; 42 ± 15 y; BMI 28.3 ± 5.6 kg/m2; plasma glucose 100 ± 8 mg/dL) consumed 28 g/d of dry roasted, unsalted, peanuts (164 kcal; 11% E carbohydrate, 17% E protein, 73% E fat, and 2.4 g fiber) or a LFHC snack (164 kcal; 53% E carbohydrate, 17% E protein, 33% E fat, and 3 g fiber) for 6-wk (4-wk washout period). Gut bacterial composition was measured using 16S rRNA sequencing in the whole cohort. Exploratory metatranscriptomic analyses were conducted on a random subset (n = 24) of samples from the Peanut condition. Results: No between-condition differences in α- or β- diversity were observed. Following peanut intake, Ruminococcaceae were significantly more abundant [Linear discriminant analysis score (LDA) = 2.8; P = 0.027)] compared to LFHC. Metatranscriptomics showed increased expression of the K03518 (aerobic carbon-monoxide dehydrogenase small subunit) gene following peanut intake (LDA = 2.0; P = 0.004) and Roseburia intestinalis L1-82 was identified as a contributor to the increased expression. Conclusion: An increased abundance of Ruminococcaceae was observed following consumption of 28 g/d of peanuts in adults with elevated fasting glucose after 6-wks. Metatranscriptomics revealed increased expression of the K03518 gene. These results suggest peanut intake enriches a known butyrate producer and the increased expression of a gene implicated in butyrate production adds further support for peanut-induced gut microbiome modulation.