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Effects of Food Form and Fitness on Appetite and Digestion.

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01070199
Recruitment Status : Completed
First Posted : February 17, 2010
Last Update Posted : July 25, 2011
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Information provided by:
Purdue University

Brief Summary:
Energy-yielding fluids induce weaker appetitive and compensatory dietary responses than energy-matched semi-solids or solids. This is problematic because the high and increasing contribution of energy from beverages in the diet may enhance positive energy balance and weight gain. The prevailing view of the overweight/obesity problem is that it stems from a small, sustained positive energy balance. It follows then that only small changes, perhaps manipulations in the rheological characteristics of the diet, will be required to correct the problem. Certain populations that are more prone to weight gain may benefit from such manipulations. Obese individuals have a higher beverage intake and experience greater weight loss with reductions in beverage intake. Further, there is evidence that obese individuals consume more energy after a liquid pre-load than their lean counterparts, yet there is no difference in energy intake after a solid load. In contrast, habitual exercisers have been shown to have an increased accuracy of short-term regulation of food intake at meals following liquid preloads. A better understanding of the mechanisms by which beverages and energy-matched solid food forms elicit differential appetitive and dietary responses in these populations needed. This research will attempt to identify the influence of physical fitness and body fat on the ability to compensate for the energy content of solid and liquid preloads by reduction in energy intake at a subsequent ad libitum meal (i.e., acute compensation) and over the course of the day (i.e., short-term compensation). Furthermore, this study will examine the cognitive contribution to differential responses to energy-matched beverage and solid food forms and the effects of mastication on appetite, GI transit, glycemic response, and selected endocrine responses.

Condition or disease Intervention/treatment Phase
High and Increasing Contribution of Energy From Beverages in the Diet May Enhance Positive Energy Balance and Weight Gain Behavioral: liquid to liquid Behavioral: liquid to solid Behavioral: solid to liquid Behavioral: solid to solid Not Applicable

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 81 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Effects of Food Form and Fitness on Appetite and Digestion.
Study Start Date : January 2009
Actual Primary Completion Date : December 2009
Actual Study Completion Date : December 2010

Arm Intervention/treatment
Experimental: liquid to liquid, Behavioral: liquid to liquid
• One test session will involve presentation of a glass of clear cherry-flavored unthickened beverage (Kool-Aid, Kraft Foods Inc., White Plains, NY). This session will be referred to as the "Liquid to Liquid" session as the participants will be consuming a liquid and be told that the consistency in their stomach will be a liquid.
Other Name: Liquid test load

Experimental: liquid to solid, Behavioral: liquid to solid
This session involves a solution of calcium chloride and a solution of sodium alginate. The participant will be instructed to pour the cherry-flavored beverage/alginate solution into the calcium chloride. The result is a solid mass. They are allowed to examine the solution to confirm the solid texture and consistency.Participants will be told that this same reaction will occur in their stomach when the session's beverage is consumed due to the effect of gastric acid on the solution. But, the participant will be consuming the same cherry-flavored beverage as in the 1st session. Thus, they will believe that their GI tract will be challenged with a solid mass, but in reality, the challenge is the same (i.e., liquid).Therefore, the only difference between the test sessions is expectation.
Other Name: liquid test load

Experimental: solid to liquid Behavioral: solid to liquid
• This session will involve the same dense gelatin cubes previously described, but participants will be told that the solid cubes will turn to liquid when they come into contact with the acid in their stomach. This trial will be known as "Solid to Liquid". A demonstration of the "Solid to Solid" and "Solid to Liquid" phases will be shown to the participant before they consume the load. Both phases exhibited by placing two cubes into separate containers filled with similar looking clear liquids. The "Solid to Solid" phase container will contain cold water so the cube stays in solid form. The "Solid to Liquid" phase container will contain hot water that will quickly dissolve the cube into a liquid form.
Other Name: liquid test load

Experimental: solid to solid Behavioral: solid to solid
Participants will be presented with dense gelatin cubes. These 1" x 1" x 1" cubes will have a solid appearance and require mastication, but is isocaloric to the beverage. However, after mastication and gastric processing, the solid rapidly breaks down into a clear fluid.However, participants will be informed that the cubes will remain the same solid consistency in their stomach. The masticatory process and stimulus form will be standardized through the use of a metronome. Participants will be required to chew the solid cube at a fixed rate prior to swallowing. Thus, adding to the cognitive impression that they are eating a solid when essentially the GI challenge will be similar to the beverage.
Other Name: liquid test load

Primary Outcome Measures :
  1. Change of energy intake. [ Time Frame: 24 hours ]
    Effects of actual and perceived food form on short term energy intake in lean and obese, fit and unfit adults.

Secondary Outcome Measures :
  1. Change of appetite. [ Time Frame: 4 hours ]
    Effects of actual and perceived food form on hunger, fullness, desire to eat, and thirst.

  2. Gastric emptying [ Time Frame: 4 hours ]
    Effects of actual and perceived food form on gastric emptying time.

  3. Gastro-intestinal transit [ Time Frame: 4 hours ]
    Effects of actual and perceived food form on gastro-intestinal transit time.

  4. Endocrin responses [ Time Frame: 4 hours ]
    Effects of actual and perceived food form on GLP-1, CCK, Insulin, Ghrelin concentration.

  5. Glucose response [ Time Frame: 4 hours ]
    Effects of actual and perceived food form on serum glucose concentration.

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • 18-50 years of age BMI of 18-23 kg/m2 (lean) or 30-35 kg/m2 (obese) Sedentary physical activity level (<70th¬ percentile of estimated VO2max for age and sex) or physically Active/Exercisers (>70th¬ percentile of estimated VO2max for age and sex) Good health and not taking any medications known to influence appetite Non-smokers Not pregnant or lactating Weight stable (≤ 3 kg within last 3 months) Dietary restraint score <11 on the Three Factor Eating Questionnaire (included in the on-line screening questionnaire) Glucose Tolerant or Non-Diabetic (fasting blood glucose of <100 mg/dL) Self-reported consumer of breakfast and lunch

Exclusion Criteria:

  • History or presence of significant metabolic diseases that may impact study results (i.e., endocrine, hepatic, renal disease) Individuals planning on starting a new diet or exercise regimen during the course of the study Use of obesity pharmacotherapeutic agents or over-the counter anti-obesity agents within the last 3 months Underlying conditions such as any cardiovascular, pulmonary, or neurological dysfunction that may be aggravated with exercise

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01070199

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United States, Indiana
Purdue University
West Lafayette, Indiana, United States, 47907
Sponsors and Collaborators
Purdue University
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Richard Mattes, PhD, Purdue University Identifier: NCT01070199    
Other Study ID Numbers: R01DK079913 ( U.S. NIH Grant/Contract )
R01DK079913 ( U.S. NIH Grant/Contract )
0805006922 ( Other Identifier: Purdue University )
First Posted: February 17, 2010    Key Record Dates
Last Update Posted: July 25, 2011
Last Verified: July 2011
Keywords provided by Purdue University:
obese, liquid, solid, fitness, humans, appetite
Additional relevant MeSH terms:
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Weight Gain
Body Weight Changes
Body Weight