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Completed

NCT Number: NCT03412136

The Acute Effect of Protein or Carbohydrate Intake on Testosterone Levels and Food Intake in Children and Adolescent Boys

The purpose of this study was to determine the effect of acute protein and glucose intake on testosterone levels measured in adolescent boys and determine whether changes in testosterone levels are associated with alterations in short-term food intake. It was hypothesized that 1) ingestion of a protein beverage would result in no change of testosterone levels whereas glucose would result in a significant decrease of testosterone levels 60 minutes after ingestion and 2) decreases of testosterone levels as a result of the glucose preload would predict food intake for boys of similar body size. The first objective was to investigate the effect of an acute protein or glucose drink on testosterone levels and the second objective was to determine whether changes of testosterone levels associate with food intake.

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Key information

Conditions

Appetitive Behavior Behavior Behavior, Animal Body Weight Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Pediatric Obesity Signs and Symptoms

Age range

9 year–18 year

Sex eligibility

Male

Study type

Interventional

Phase

Not applicable

Primary location

University of Toronto

Toronto, Ontario, M5S 3E2, Canada

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 9-18 years, healthy, male.

Exclusion criteria

  • History of prematurity, chronic illness, were taking any medications known to affect glucose homeostasis, appetite or pubertal development.

Treatment and study plan

Control

Dietary Supplement

Participants were given 5 minutes to ingest the non-caloric beverage which contained 1.5ml of chocolate extract (Vanilla Food Company, Markham, Ontario, Canada) to account for the flavor differences and mixed with 500ml of water and sweetened with 0.2g sucralose (Tate & Lyle, Stoney Creek, Ontario, Canada) in order to match sweetness with the glucose beverage.

Glucose

Dietary Supplement

Participants were given 5 minutes to ingest the beverage which contained either 1g of protein (plain whey-protein isolate; BiPro USA., Eden Prairie, Minnesota, U.S.A) per kg of bodyweight and was flavoured with 1.5ml of chocolate extract (Vanilla Food Company, Markham, Ontario, Canada) to account for the flavor differences and mixed with 500ml of water.

Protein

Dietary Supplement

Participants were given 5 minutes to ingest the beverage which contained 1g of glucose monohydrate (BioShop Canada Inc., Burlington, Ontario, Canada) per kg of bodyweight and flavoured with 1.5ml of chocolate extract (Vanilla Food Company, Markham, Ontario, Canada) to account for the flavor differences and mixed with 500ml of water.

Primary outcomes

  1. Testosterone Change

    Time frame: 0-65 minutes

    The first blood draw was taken prior to ingesting the experimental beverage at baseline (0 minutes). Participants were then given 5 minutes to ingest the beverage, and blood was later obtained 20, 35 and 65 minutes after baseline blood draw. Units were measured in ng/dl.

Secondary outcomes

  1. Appetite Biomarkers- Glucose

    Time frame: 0-85 minutes

    Glucose. Units were measured in mg/dl.

  2. Appetite Biomarkers- Glucagon-like peptide-1

    Time frame: 0-85 minutes

    Glucagon-like peptide-1. Units were measured in pM.

  3. Appetite Biomarkers- Active Ghrelin

    Time frame: 0-85 minutes

    Active Ghrelin. Units were measured in pg/ml.

  4. Appetite Biomarkers- Insulin

    Time frame: 0-85 minutes

    Insulin. Units were measured in uIu/ml.

  5. Subjective Appetite- Determination to eat

    Time frame: 0-85 minutes

    Visual Analog Scales were employed to assess subjective appetite based on the Determination to Eat. Units were measured in mm (based on a 100mm scale).

  6. Subjective Appetite- Hunger

    Time frame: 0-85 minutes

    Visual Analog Scales were employed to assess subjective appetite based on feelings of Hunger. Units were measured in mm (based on a 100mm scale).

  7. Subjective Appetite- Fullness

    Time frame: 0-85 minutes

    Visual Analog Scales were employed to assess subjective appetite based on feelings of FullnessUnits were measured in mm (based on a 100mm scale).

  8. Subjective Appetite- Prospective Food Consumption

    Time frame: 0-85 minutes

    Visual Analog Scales were employed to assess subjective appetite based on Prospective Food Consumption. Units were measured in mm (based on a 100mm scale).

  9. Food Intake

    Time frame: 65-85 minutes

    Participants were provided an ad libitum pizza meal. The participants were instructed to eat during the next 20 min until they were comfortably full. Based on the participant preferences determined during screening, two varieties of Deep 'N Delicious 5-inch-diameter pizza were provided for consumption; pepperoni and three-cheese pizzas (McCain Canada Ltd., Florenceville, Ontario, Canada). Units were measuring in kcal.

Sponsors and collaborators

Lead sponsor

University of Toronto

Other

Collaborators

  • Canadian Institutes of Health Research (CIHR)

Registry information

Official study title

Acute Decrease in Serum Testosterone After Glucose and Protein Beverages in Adolescent Males

Important dates

Study start
2014
Primary completion
2016
Study completion
2016
First posted
Jan 26, 2018
Registry last updated
Jan 26, 2018

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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