Eating Behaviors Among Weight-Discordant Siblings

Study Overview
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Brief Summary
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The purpose of this study was to compare weight-discordant siblings in eating in the absence of hunger, caloric compensation, and the quality of their habitual diet. The investigator hypothesized that, within families and controlling for age differences, overweight and obese siblings would show greater eating in the absence of hunger, poorer caloric compensation, and poorer diet quality (e.g., increased percent of energy from fat and caloric beverages) compared to normal-weight siblings.

Detailed Description
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The study used a discordant sibling design to compare putative obesity-promoting eating traits among siblings, 5-12 years, who were raised in the same household, but were discordant for weight status (normal-weight: BMI-for-age between 5 and less than the 85th percentile; overweight/obese: BMI-for-age greater or equal to the 85th percentile). Forty-seven pairs of same-sex siblings (boys and girls) were recruited from the greater Philadelphia area to participate in a 4-week study during which their eating behaviors and body composition were assessed. The study tested the hypotheses that overweight/obese, compared to normal-weight, siblings exhibit 1) a weaker ability to compensate for calories, 2) a greater susceptibility towards eating in the absence of hunger, and 3) habitual dietary intakes that favor increased dietary energy density (kcal/g) and increased %energy derived from fat and caloric beverages. The use of a behavioral genetics design to study eating phenotypes among siblings is a unique approach to elucidate shared and non-shared environmental influences that can contribute to variations in weight status during childhood.

Official Title
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Eating Behaviors Among Weight-Discordant Siblings

Conditions
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Obesity

Intervention / Treatment
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* Other: Feeding study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: same-sex; weight discordant (normal-weight vs. overweight/obese); meet age criteria; like most foods that were served in the study. Exclusion Criteria: serious medical conditions or medication use known to affect appetite, food intake and body weight; developmental or psychiatric conditions; food allergies or nutrient intolerances (including lactose intolerance).

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 12 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: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low energy-dense preload<br> | Other: Feeding study<br>* In a crossover design, siblings were served dinner once a week for 3 weeks. Across conditions, siblings were served the same dinner, but, 25 minutes before dinner, they either consumed in full or did not consume one of two preloads that varied in energy density. On the day when no preload was consumed, eating in the absence of hunger was assessed after dinner and defined as the number of calories consumed from snacks. Habitual dietary intake was assessed using 24-hour dietary recalls.<br>|
| Experimental: High energy-dense preload<br> | Other: Feeding study<br>* In a crossover design, siblings were served dinner once a week for 3 weeks. Across conditions, siblings were served the same dinner, but, 25 minutes before dinner, they either consumed in full or did not consume one of two preloads that varied in energy density. On the day when no preload was consumed, eating in the absence of hunger was assessed after dinner and defined as the number of calories consumed from snacks. Habitual dietary intake was assessed using 24-hour dietary recalls.<br>|
| Experimental: No preload<br> | Other: Feeding study<br>* In a crossover design, siblings were served dinner once a week for 3 weeks. Across conditions, siblings were served the same dinner, but, 25 minutes before dinner, they either consumed in full or did not consume one of two preloads that varied in energy density. On the day when no preload was consumed, eating in the absence of hunger was assessed after dinner and defined as the number of calories consumed from snacks. Habitual dietary intake was assessed using 24-hour dietary recalls.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Energy intake | %COMPX, EAH, dietary intake variables | Up to 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body composition | Weight status (BMI-for-age percentile), BMI z-score, total body fat (%), waist circumference (cm), skinfold thickness (mm) | Single assessment at Week 4 |