Healthy Prebiotic and Postbiotic Effects of Peanuts and Peanut Butter: College Intervention Trial
Condition: Microbiota; Cognitive Change
Study type: Interventional

Summary: 
      Nuts have a prebiotic effect mainly due to their content of fiber and polyphenols, which
      provide substrates for the human gut microbiota. It is known that prebiotic substances are
      metabolized by microbiota generating postbiotics substances (products or metabolic
      by-products secreted by live bacteria or released after bacterial lysis). These products may
      improve host health and partly explain the health benefits of nut consumption. However, no
      study has been performed about the pre- and postbiotic effects of peanut and peanut butter
      consumption. Therefore, researchers propose a new interventional study to assess the impact
      of daily peanut and peanut butter intake on the organism, evaluating the pre- and postbiotic
      effects. The metabolome data generated will be correlated with the beneficial effects and
      cognitive skills. The final aim of this work is to spread a message of the health benefits of
      peanut consumption for the general population.
    

Detailed description: 
      To evaluate the possible changes in microbiota and cognitive skills after consumption of
      roasted peanuts and peanut butter, a three-arm parallel-group randomized, and controlled
      study is being carried out. Ninety healthy college students were enrolled, according to the
      sample size estimated. Blood, urine, feces and saliva are being drawing at baseline, 3 and 6
      months. Peripheral blood mononuclear cells are being extracted to evaluate the metabolic
      changes caused by the proposed nutritional interventions. To assess diet and physical
      activity a 151-items food frequency questionnaire plus a 7-day dietary record and a validated
      questionnaire Minnesota are being used. To determinate the effects of the intervention on
      body composition and vascular risk factors, anthropometric, biochemical and clinical
      measurements are being collected. Possible changes in cognitive skills will be determined
      from a validated cognitive questionnaire (WAIS-IV, Wechsler Memory Scale-IV (WMS-IV), COPE
      and HAD). To evaluate inflammation and metabolic status before and after intervention, levels
      of hormones and signaling molecules will be analyzed in blood samples. The effect of roasted
      peanut and peanut butter consumption on microbiota will be assayed through identification and
      quantification of polyphenols and short-chain fatty acids in biological samples, as well as
      the gut microbiota characterization from DNA extraction.
    

Intervention name(s): Roasted peanuts (group A); Peanut butter (group B); Control (group C)
Intervention type(s): Other; Other; Other
Intervention description(s): After 2 weeks following a peanut-free diet, the participants of this group consume 25 g/ day of whole skin roasted peanuts (RP) within the habitual diet during 6 months.; After 2 weeks following a peanut-free diet, the participants of this group consume 2 tbsp/ day (32 g/ day) of peanut butter (PB) within the habitual diet during 6 months.; After 2 weeks following a peanut-free diet, the participants of this group consume 2 tbsp/ day (32 g/ day) of control supplement (containing the same proportion of macronutrients as peanuts and peanut butter) within the habitual diet during 6 months.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Group A: Habitual diet + 25 g/day of whole skin roasted peanuts (RP) Group B: Habitual diet+ 2 tbsp/day (32 g/day) of peanut butter (PB) Group C: Habitual diet + control supplement (containing the same proportion of macronutrients as in the intervention)
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: peanuts; peanut butter; microbiota; cognitive skills; polyphenols; short-chain fatty acids; inflammation; vascular