Macronutrients and Satiety in Older and Younger Adults

Study Overview
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Brief Summary
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This study aims to compare the effect of meals high in protein, fat and carbohydrate but equal in energy and volume on energy intake, perceived appetite and gastric emptying in younger (<40 years) and older (> 65 years) people living in the United Kingdom (UK).

Detailed Description
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To assess if increasing protein intake in older adults will have a compensatory decrease in energy intake due to protein's satiating effects. To compare the effect of meals high in protein, fat and carbohydrate but equal in energy and volume on energy intake and perceived appetite in younger (<40 years) and older adults (>65 years). To compare the effect of meals high in protein, fat and carbohydrate but equal in energy and volume on gastric emptying in younger (<40 years) and older adults (>65 years).

Official Title
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The Effect of Different Macronutrients on Appetite and Satiety in Older and Younger Adults

Conditions
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Appetitive Behavior, Gastric Emptying

Intervention / Treatment
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* Other: Smoothie


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: either aged >65 years or <40 years healthy Exclusion Criteria: having a disease and/or using a medication that can impact on appetite in the past three months; having an allergy to any of the test foods; disliking or cannot eat any of the test foods; being pregnant or breastfeeding; being obese (BMI > 30 kg/m2); being on a weight loss diet; smoking more than 10 cigarettes a day.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High Carbohydrate Meal<br>A smoothie including maltodextrin and low-fat strawberry yoghurt - 289 kcal, 61g carbohydrate, 6.7g protein, 1.9g fat. | Other: Smoothie<br>* Preload smoothies that are matched for taste, smell, appearance, quantity and calorie but different caloric content.<br>|
| Experimental: High Fat Meal<br>A smoothie including double cream and low-fat strawberry yoghurt - 312 kcal, 13.3g carbohydrate, 7g protein, 25.5g fat. | Other: Smoothie<br>* Preload smoothies that are matched for taste, smell, appearance, quantity and calorie but different caloric content.<br>|
| Experimental: High Protein Meal<br>A smoothie including whey protein and low-fat strawberry yoghurt - 307 kcal, 13.6g carbohydrate, 57g protein, 2.7g fat. | Other: Smoothie<br>* Preload smoothies that are matched for taste, smell, appearance, quantity and calorie but different caloric content.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ad-libitum meal consumption | Consumption of the ad-libitum meal is measured (g). Participants are instructed to eat until they feel comfortable full and are given 20 min to consume the meal. | 3 days in total | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ratings of appetite | Appetite are assessed using a 100 mm Visual Analogue Scales (VAS, scale 0-100). | 3 days in total | 
| Gastric Emptying | Gastric emptying is measured using of 13C octanoic acid breath test | 3 days in total | 
| Ratings of palatability | Palatability ratings are assessed using a 100 mm Visual Analogue Scales (VAS, scale 0-100). | 3 days in total | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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younger adults, older adults, appetite, satiety, macronutrients