• Child and adult body mass index [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Child's and adult caregiver's weight will be assessed by an electronic scale and height will be measured by a stadiometer.
• Child and adult salivary habituation [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  To assess habituation of salivary responses to food cues, whole mouth parotid salivary flow will be measured using the Strongin-Hinsie Peck method. Two measures will be taken, one with juice and one with food.

• Child and adult dietary Intake [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Dietary intake for both the child and adult caregiver will be assessed by 3 (2 weekdays and 1 weekend day) 24-hour dietary phone recalls, using the five-step, multiple-pass method. Variables of interest will be the variety of RED foods consumed over the three days; and the mean over the three days of daily servings and kcal from RED foods, kcal, energy density (kcal/g), and Healthy Eating Index (HEI)-2015. Adherence to the prescriptions in the two conditions will be examined. At 6, 12, and 18 months, the percentage of goals met each day will be calculated, with a mean percentage calculated. We will also provide a detailed list of snack foods to participants, and they will be asked to indicate which of the foods on the list were eaten during the previous month, regardless of quantity consumed.
• Child and adult physical activity via wGT3X-BT [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  The wGT9x (ActiGraph, LLC, Pensacola, FL) will objectively measure time spent in MVPA (physical activity at > 3.0 metabolic equivalents units).
• Child percent overweight [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Percent overweight (%OW) will also be calculated (100*[BMI/50th percentile BMI for child age and sex]).
• Child and adult waist circumference [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Waist circumference (WC) will be measured using standard procedures.
• Meal planning, preparation, and grocery shopping [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Parent time scarcity and fatigue as barriers to planning and preparing meals will measure frequency of occurrence of these barriers.
• Child eating pathology [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Child eating pathology will be assessed using the Kid's Eating Disorder Survey
• Home Food Inventory [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Self-reported inventory of foods available in the household will be assessed
• Child and Adult Sleep Habits [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Usual sleeping and waking time will be collected
• Child Routines [ Time Frame: Change from 0 to 6, and 6 to 18 months ]
  Parent-report measure of commonly occurring routines in school-aged children will measure the frequency of occurrence of routines in children.
• Compliance and process data [ Time Frame: 6, 12, and 18 months ]
  Total number of weekly, and type, of self-monitoring records (hard copy or electronic) completed will be assessed. Number of treatment sessions attended will be recorded.

Identifying successful methods for reducing long-term energy intake continues to be a challenge in obesity treatment. Basic behavioral research has found that the rate of habituation (i.e., rate of reduction in physiological and behavioral responding) to food is related to amount of food consumed, and faster habituation rates reduce food intake. The rate of habituation to food can be accelerated when variety in foods is limited, producing decreased intake. Thus, a dietary prescription that limits variety of high-energy-dense (HED) foods may boost ability to reduce long-term energy intake, enhancing long-term weight loss.

Furthermore, habituation rates to food show large individual variability. For example, individuals with overweight habituate slower to food than individuals with a healthy weight, and slower habituation rates predict greater increases in child standardized body mass index (ZBMI). Thus, slower habituation rates to food may be a behavioral phenotype for increased risk of suboptimal weight outcomes. Obesity interventions that accelerate habituation to food may then be more beneficial for those with this behavioral phenotype.

The investigators have been conducting a line of translational research that applies habituation theory to obesity treatment involving: 1) studies systematically testing basic concepts to better inform intervention development; 2) "proof-of-concept" testing; and 3) efficacy trials. The long-term goal of this research is to develop a dietary prescription that harnesses habituation as a mechanism for reducing long-term energy intake. This research has culminated in piloting a limited variety prescription (variety of both HED snack foods and entrees at dinner were limited) within a 6-month family-based behavioral obesity treatment (FBT) for children. Twenty-four families, with a child > 85th percentile BMI and aged 8 to 12 years, were randomized to FBT that included the Traffic Light Diet (1000-1500 kcal/day, < 2 servings/day of RED [HED] foods) and a > 60 min/day of moderate- to vigorous-intensity physical activity prescription or to FBT that included a limited dietary variety prescription (one RED snack food and dinner entrée were chosen; families regularly consumed these foods as compared to other RED snack foods and entrees) (FBT+Variety). At 6-months children in FBT+Variety had a significantly greater reduction in percent overweight than those in FBT (-15.4% vs.- 8.9%), and families in FBT+Variety had a lower daily intake of kcal from fat (351 kcal vs. 494 kcal). This limited dietary variety prescription shows promise for enhancing weight outcomes in FBT. However, research is needed to examine if limiting variety improves long-term weight loss, if this improvement is due to enhanced habituation, and explore if there is a behavioral phenotype that more greatly benefits from this dietary approach.

The investigators plan to implement a novel limited RED food variety prescription within an 18-month FBT to examine its effect on 18-month body mass index (BMI). This will be the first RCT to examine how habituation rate, assessed via salivary habituation, mediates reduction in RED food intake, overall energy intake, and reductions in BMI over time, as well as if baseline habituation rate is a behavioral phenotype that moderates BMI outcomes. One hundred fifty-six children aged 8 to 12 years at > 85th percentile BMI will be randomized to one of two, 18-month interventions compared in our 6-month pilot study: FBT or FBT+Variety. Child and adult caregiver assessments will occur at 0, 6, 12, and 18 months on anthropometrics, dietary intake (RED food variety, energy, and diet quality), habituation, and physical activity. The investigation was designed for all intervention sessions and assessments to be conducted in person. Due to COVID-19, modifications have occurred to the trial for health safety reasons. Initially, all meetings and assessments were moved to occur remotely via Zoom. The trial is currently in a transition stage where, families choose between attending assessments in person or remote via Zoom. Intervention sessions remain remote via Zoom. Health safety guidelines are in place for all in person contact.

The primary aims are to determine for children:

1. Influence of FBT+Variety on long-term weight loss.
2. Influence of FBT+Variety on long-term habituation to RED foods. The habituation rate will mediate differences in dietary intake and BMI between conditions.

An exploratory aim is to examine in children:

1) Influence of habituation rate on moderating outcomes in FBT+Variety and FBT (identifying a behavioral phenotype that bests benefits from a limited variety prescription).

Comparisons will also be made between the conditions on all child dietary and activity measures. Additionally, adult caregiver measures will be examined, with outcomes anticipated to be similar to child outcomes.

• Obesity
• Childhood Obesity

• Behavioral: FBT
  FBT will receive a family-based, behavioral intervention for childhood obesity, consisting of group meetings once a week for months 1 to 4, twice a month for months 5 to 6, once a month for months 7 to 12, and once every two months for months 13 to 18 (29 sessions). For all meetings, the child and adult caregiver will be weighed and be provided with feedback, homework will be reviewed, and a behavioral lesson will be presented. At the 60-min meetings, the child and adult will attend separate 40 min group meetings, and then for the last 20 min of the meetings they will meet together with an individual therapist to address specific family-issues by developing behavioral action plans. No goals on variety in RED foods will be provided.
• Behavioral: FBT+Variety
  This condition is FBT with a limited variety prescription. The limited variety prescription reduces the number of different RED foods consumed.

• Active Comparator: FBT (family-based behavioral treatment)
  This condition will be prescribed the Traffic Light Diet (1000-1500 kcal/day, < 2 servings/day of RED [non-nutrient-dense, energy-dense] foods) and a > 60 min/day of MVPA prescription for children and > 30 min/day of MVPA for adults at least 5 days/week. FBT will receive a family-based, behavioral intervention to assist the targeted child and a participating adult caregiver with making changes in energy balance behaviors.
  Intervention: Behavioral: FBT
• Experimental: FBT+Variety
  The FBT+Variety condition will receive FBT along with a limited variety prescription. In this prescription families will identify two RED foods, a dinner entree and snack food, and develop meal plans that reduce variety of RED foods by regularly consuming these foods and limiting consumption of other RED entrees and snack foods.
  Intervention: Behavioral: FBT+Variety

• Altman M, Wilfley DE. Evidence update on the treatment of overweight and obesity in children and adolescents. J Clin Child Adolesc Psychol. 2015;44(4):521-37. doi: 10.1080/15374416.2014.963854. Epub 2014 Dec 12. Review.
• Epstein LH, Temple JL, Roemmich JN, Bouton ME. Habituation as a determinant of human food intake. Psychol Rev. 2009 Apr;116(2):384-407. doi: 10.1037/a0015074. Review.
• Epstein LH, Robinson JL, Temple JL, Roemmich JN, Marusewski AL, Nadbrzuch RL. Variety influences habituation of motivated behavior for food and energy intake in children. Am J Clin Nutr. 2009 Mar;89(3):746-54. doi: 10.3945/ajcn.2008.26911. Epub 2009 Jan 28.
• Temple JL, Giacomelli AM, Roemmich JN, Epstein LH. Dietary variety impairs habituation in children. Health Psychol. 2008 Jan;27(1S):S10-9. doi: 10.1037/0278-6133.27.1.S10.
• Epstein LH, Fletcher KD, O'Neill J, Roemmich JN, Raynor H, Bouton ME. Food characteristics, long-term habituation and energy intake. Laboratory and field studies. Appetite. 2013 Jan;60(1):40-50. doi: 10.1016/j.appet.2012.08.030. Epub 2012 Oct 22.
• Epstein LH, Robinson JL, Temple JL, Roemmich JN, Marusewski A, Nadbrzuch R. Sensitization and habituation of motivated behavior in overweight and non-overweight children. Learn Motiv. 2008 Aug;39(3):243-255.
• Bond DS, Raynor HA, McCaffery JM, Wing RR. Salivary habituation to food stimuli in successful weight loss maintainers, obese and normal-weight adults. Int J Obes (Lond). 2010 Mar;34(3):593-6. doi: 10.1038/ijo.2009.267. Epub 2009 Dec 15.
• Bond DS, Raynor HA, Vithiananthan S, Sax HC, Pohl D, Roye GD, Ryder BA, Wing RR. Differences in salivary habituation to a taste stimulus in bariatric surgery candidates and normal-weight controls. Obes Surg. 2009 Jul;19(7):873-8. doi: 10.1007/s11695-009-9861-3. Epub 2009 May 20.
• Epstein LH, Carr KA, Cavanaugh MD, Paluch RA, Bouton ME. Long-term habituation to food in obese and nonobese women. Am J Clin Nutr. 2011 Aug;94(2):371-6. doi: 10.3945/ajcn.110.009035. Epub 2011 May 18.
• Temple JL, Giacomelli AM, Roemmich JN, Epstein LH. Overweight children habituate slower than non-overweight children to food. Physiol Behav. 2007 Jun 8;91(2-3):250-4. Epub 2007 Mar 16.
• Aspen VA, Stein RI, Wilfley DE. An exploration of salivation patterns in normal weight and obese children. Appetite. 2012 Apr;58(2):539-42. doi: 10.1016/j.appet.2011.11.027. Epub 2011 Dec 3.
• Epstein LH, Kilanowski C, Paluch RA, Raynor H, Daniel TO. Reducing variety enhances effectiveness of family-based treatment for pediatric obesity. Eat Behav. 2015 Apr;17:140-3. doi: 10.1016/j.eatbeh.2015.02.001. Epub 2015 Feb 13.

Inclusion Criteria:

• age between 8 and 12 years
• > 85th percentile BMI
• one adult caregiver (> 18 years) living in the household with a BMI > 25 kg/m2 willing to attend treatment meetings

Exclusion Criteria:

• child and adult caregiver report living in two separate households for > 2 days per week
• child or adult caregiver report a heart condition, chest pain during periods of activity or rest, or loss of consciousness on the Physical Activity Readiness Questionnaire (PAR-Q) (individuals reporting joint problems, prescription medication usage, or other medical conditions that could limit exercise will be required to obtain written physician consent to participate)
• child or adult caregiver report being unable to walk for 2 blocks (1/4 mile) without stopping
• child or adult caregiver report major psychiatric diseases or organic brain syndromes
• child or adult caregiver report currently participating in a weight loss program and/or taking weight loss or appetite regulation medication or lost > 5% of body weight during the past 6 months
• child report having bariatric surgery for weight loss/planning to have bariatric surgery in the next 18 months, adult caregiver having bariatric surgery in the previous two years or planning to have bariatric surgery in the next 18 months
• adult caregiver reports being pregnant, lactating, less than 6 months post-partum or plans to become pregnant in the next 18 months
• child or adult caregiver report planning to move outside of the metropolitan area within the time frame of the investigation
• child or adult caregiver report dietary restrictions for medical reasons
• child or adult caregiver report allergies to lemon or lime juice (used in habituation measures)
• child is not able to read at a third-grade reading level.
• do not have reliable internet access.

• National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
• The Miriam Hospital
• University of Memphis
• University at Buffalo