A Pilot Test of Mood and Circadian Rhythm Mechanisms Driving Binge Eating

Summary

Mood and circadian rhythm disruptions are associated with binge eating (BE). BE is a discrete, episodic behavior characterized by 1) eating an objectively large amount of food and 2) experiencing a subjective sense of loss of control. BE episodes are often preceded by negative mood states, and a subtype of individuals with BE has high levels of negative moods. This group has more comorbid psychopathology and a poorer response to treatment. Thus, understanding the role of negative mood is a critical area for research on BE. Individuals with BE demonstrate disruptions in several circadian rhythms, including diurnal meal timing, hormone patterns (e.g., daily cortisol rhythms), and mood variations. The most potent synchronizer of circadian rhythms is light. Thus, exposure to light may explain other phenomena that fluctuate similarly, such as mood and the occurrence of BE. Mood is subject to the influence of light, and BE is also influenced by exposure to bright light. It is unknown whether regulating circadian rhythms via regular exposure to light improves BE through its effects on mood or via changes in other biological or behavioral rhythms. This knowledge can inform the development of treatments targeting biobehavioral mechanisms that maintain BE and indicate for whom this may be most effective. This project aims to test the roles of negative mood and circadian rhythms in the relationship between light exposure and BE and identify subtypes of individuals in whom this effect is strong. The investigators hypothesize that individuals exposed to less natural bright light will experience more frequent BE, more negative mood, and a blunted morning cortisol response. The investigators further hypothesize that manipulating exposure to artificial bright light will reduce the frequency of BE and negative mood and increase the morning cortisol response. Finally, the investigators hypothesize that the effects of this artificial bright light exposure on BE frequency will be mediated by changes in negative mood, which itself will be accounted for by changes in circadian rhythms as indicated by the morning cortisol response. Additionally, the investigators have two moderation hypotheses: that the effects of artificial bright light exposure on BE will be greater for those who fit the high negative mood type than those who do not and that the effects will be greater for individuals with a blunted morning cortisol response at baseline than for those without.

Conditions

• Eating Disorder
• Binge Eating
• Circadian Dysregulation

Interventions

DEVICE

Bright Light Exposure

For 10 consecutive days, participants will use an Ultralux(R) V HD-LED light therapy light for 30 minutes beginning 30 minutes after waking. The light will be preset to deliver \~10,000 lux at 22".

DEVICE

Natural Light Exposure

For 10 consecutive days, participants will use an Ultralux(R) V HD-LED light therapy light for 30 minutes beginning 30 minutes after waking. The light will be preset to deliver \~500 lux at 22".

Sponsors & Collaborators

• University of Wyoming

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-02-15

Primary Completion

2020-03-15

Completion

2020-03-15

Countries

• United States

Study Locations