Think AHEAD (A Healthy Eating And Drinking) Study

• Body fat percentage [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Body circumferences [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Urine specific gravity [ Time Frame: Change throughout 6 months ] [ Designated as safety issue: No ]
• Hunger, satiety, and palatability ratings [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Diet quality [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Satisfaction rating [ Time Frame: 6 months ] [ Designated as safety issue: No ]
• Immune status [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Cardiovascular risk factors [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Diabetes risk factors [ Time Frame: 6 month change ] [ Designated as safety issue: No ]

• Body fat percentage [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Body circumferences [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Urine specific gravity [ Time Frame: Change throughout 6 months ] [ Designated as safety issue: No ]
• Hunger rating [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Diet quality [ Time Frame: 6 month change ] [ Designated as safety issue: No ]
• Satisfaction rating [ Time Frame: 6 months ] [ Designated as safety issue: No ]

Advice to increase water consumption as part of a weight-reducing diet - typically to 8 cups (64 fl oz, ~2 L) per day ("8x8" water recommendation) - is almost ubiquitously recommended by healthcare professionals. Many believe that water promotes weight loss through numerous physiological mechanisms. However, only limited observational data and virtually no experimental data exist regarding the effects of water consumption on body weight. In this study, we propose a randomized controlled pilot study in which two groups of overweight adolescents will receive a standard weight loss regimen, either with (experimental intervention) or without (control intervention) additional advice and support to increase water consumption. We will utilize individual sessions, an innovative text messaging protocol, and motivational telephone calls to promote adherence to the interventions. The purpose of this pilot study is to evaluate feasibility and obtain preliminary efficacy data, to inform design of a future, definitive study.

It is hypothesized that increasing water consumption will improve the efficacy of a standard weight-reducing diet and will lead to decreased consumption of energy-containing beverages, decreased total energy intake, improved diet quality, improved immune status, and improved cardiovascular and diabetes risk factors. This simple behavioral intervention will be feasible and will significantly increase water consumption among participants in the experimental vs. control group.

This is a 6-month randomized controlled trial. After the initial baseline screening and assessments, 60 overweight adolescents will be randomly assigned (30 subjects per group) to a standard weight-reducing diet with the advice to consume 8 cups of water per day (experimental group) or the same standard weight-reducing diet without additional advice (control group). The interventions will consist of nutrition education and behavioral counseling by a registered dietitian, during individual sessions and telephone calls. Mobile text messaging will be used to reinforce information presented at the individual sessions and thereby foster adherence to dietary advice. Diet prescriptions will differ only in regard to the specificity of recommendations regarding water consumption and physical activity recommendations will not differ between groups. The frequency and content of text messages will be consistent between the experimental and control groups, with the exception that the experimental group will receive an additional phrase with each message to encourage the "8 x8" water recommendation.

A registered dietitian will communicate with each participant one time per month, either during an individual session or by telephone. Individual sessions will include nutrition classes, cooking demonstrations, taste testing, hands-on activities, and opportunities for questions and answers. Text messages will be sent on a daily basis.

Study outcomes will be assessed at baseline and at regular intervals throughout the 6 months of the study.

• Experimental: Diet + Water
  Participants will be counseled to follow a standard weight-reducing diet including consumption of 1) ample vegetables, fruits, and legumes; 2) whole rather than refined grains; and 3) high-quality proteins at most meals and snacks. Moreover, we will recommend limiting intake of added fats and sugars and avoiding juices and sugar-sweetened beverages (per standard practice). Participants will also be counseled to increase their water intake to 8 cups per day, consistent with the popular "8 × 8" recommendation (eight 8-oz glasses of water).
  Intervention: Behavioral: Dietary counseling
• Active Comparator: Diet
  Participants will be counseled on the same standard weight-reducing diet, as described above, with no specific advice regarding water consumption. Furthermore, no specific dietary recommendations will be provided on altering fluid/beverage intake, other than to decrease calorie-containing beverages as noted above. When participants ask for a recommendation regarding water intake, they will be advised that drinking plain water is the best way to satisfy thirst and instructed to drink when thirsty.
  Intervention: Behavioral: Dietary counseling

Inclusion Criteria:

• BMI ≥ 85th percentile for sex and age according to CDC growth charts
• Access to a working telephone and cell phone
• At least one parent willing and able to participate in the intervention with the subject
• Residing in predominately one household (no more than one weekend every two weeks in a secondary household)
• Medical clearance from a primary care provider or treating physician to rule out any major medical illness, disability, or disorder (e.g., liver disease, renal failure, cancer)

Exclusion Criteria:

• Intake of more than 4 cups (250 mL per cup) of water per day
• BMI ≥ 40 kg/m2
• Currently smoking (> 1 cigarette in the past week)
• Major surgery within the previous 6 months
• Does not have a primary care provider
• Physician diagnosis of a major medical illness (e.g. diabetes)
• Previous diagnosis of an eating disorder
• Physical, mental, or cognitive handicaps that prevent participation
• Chronic use of medications that may affect study outcomes (e.g. stimulants or diuretics)
• Another member of the family (first degree relative) or household participating in the study
• A friend, classmate or coworker participating in the study with whom they have contact with one or more times per week
• Girls who are pregnant, planning to become pregnant in the next 6 months, lactating, or within 6 months postpartum