Increasing in Chewing Number Reduces Energy Intake in Healthy Weight and Overweight Young Adults
Condition: Mastication
MeSH terms: Overweight
Study type: Interventional

Summary: 
      A randomized cross-over design aims to investigate chewing activities between healthy vs.
      overweight and determine effects chewing times on energy intake and postprandial plasma
      glucose and insulin. Forty-one participants were allocated into lean and overweight groups
      according to BMI. Phase I, Bite size (g/bite), bite rate (bites/min), chewing frequency
      (chews/min), and chews (chews/g food) were recorded after a sandwich breakfast. Phase II,
      gram of sandwich eaten ad libitum after 15 and 50 chew per bite (number from phase I) were
      recorded. Postprandial plasma glucose and insulin were examined at 0 (baseline), 30, 60, 90,
      120 and 180 min.
    

Detailed description: 
      Forty-one eligible participants were divided into 2 groups; lean and overweight according to
      their BMI [lean BMI (kg/m2) ≥ 18.5 and < 23, overweight BMI ≥23]

      Phase I: investigate the differences of chewing activities between healthy weight and
      overweight participants.

      The day before the clinic visit, participants were requested to consume only portion control
      of fried rice with egg for their dinner at 6 -7 pm. No other foods or drinks were allowed
      after provided dinner. The next morning, participants arrived at the clinic between 7-8 am
      after a 12 hours overnight fast and a 24 hours period without exercise. Sandwich was served
      with 300 ml. of water for breakfast ad libitum. Foods consumed were recorded. A digital
      camera recorded each participants chewing activities including bite size (g/bite); the ratio
      of food weight to bite number, bite rate (bites/min); the ratio of bite number to meal time,
      chewing frequency (chews/min); the ratio of chews to meal time, chews (chews/g food); the
      ratio of chews to meal weight.

      Phase II: investigate the effects 15 chews and 50 chews on energy intake, hunger, satiety,
      appetite, postprandial plasma glucose and insulin in both healthy weight and overweight
      participants Participants were allocated into 2 groups of a 15 chews and 50 chews per bites
      with 2 weeks of wash-out period. The day before the clinic visit, participants were requested
      to consume only portion control of fried rice with egg for their dinner at 6 -7 pm. No other
      foods or drinks were allowed after provided dinner in order to prevent confounding factors of
      previous food consumption. On the next day, participants arrived at the clinic between 7-8 am
      after a 12 hours overnight fast and a 24 hours period without exercise. At clinic visit,
      baseline characteristics including anthropometry, hunger, satiety, appetite, and plasma
      glucose and insulin concentrations were collected before breakfast was served. Participant
      was requested to rate their hunger, satiety and appetite using a visual analogue scale (VAS)
      questionnaire.

      After collecting baseline indicators, participants were served an ad libitum sandwich and 300
      ml water for breakfast. Participants had to finish their breakfast within 20 min after first
      bite. VAS questionnaire and blood samples of postprandial glucose and insulin were examined
      at 0 (baseline) 30, 60, 90, 120 and 180 min after test meal. Blood samples was collected from
      indwelling catheters at mentioned time points.
    

Intervention name(s): Food - Sandwich
Intervention type(s): Other
Intervention description(s): Sandwich as a breakfast for testing chewing activities.
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Randomized cross-over design
Masking: None (Open Label)
Primary purpose: Health Services Research