decided to shift to a new design and measures

This is a pilot trial to examine the acceptability and feasibility of time-restricted eating as an adjunct to medication treatment for bipolar disorder.

Time-restricted eating (TRE) is a way of scheduling food intake that has been shown to improve circadian rhythms in animals and humans. TRE is based on animal and human science that shows that the timing of eating powerfully influences diurnal rhythms. Animal research has shown that feeding during sleep periods leads to a surge of norepinephrine, cortisol, wakefulness, and activity. Drawing on this, over a decade of studies have examined the impact of experimentally randomizing mice to time-restricted feeding during wake hours (vs. 24-hour ad libitum feeding). Importantly, caloric intake and other facets of diet were yoked for strict control. A consistent finding is that TRE had powerful benefits for circadian and metabolic indicators across studies,and more recent data also shows benefit for animal longevity.

Here, the investigators' goal is to extend this work to bipolar disorder (BD). More specifically, the investigators will gather data to examine the acceptability and feasibility of TRE among those who self-identify with bipolar disorder and who experience some problems with sleep, circadian rhythms, or schedules. The investigators will gather measures of mania, depression, sleep, and QOL, to provide preliminary evidence of change on these dimensions.

Inclusion Criteria:

• adults diagnosed with bipolar disorder and currently receiving medical care for their bipolar disorder.
• Experiencing schedule/sleep or circadian problem in the past 3 months
• Medication regimens stable for past month
• Adequate English language skills for taking part in the program.
• Living in California.

Exclusion Criteria:

• Cognitive deficits (Screening OMC Test)

• Current: psychosis, (hypo)mania, major depressive episode, substance/alcohol use disorders, eating disorder diagnoses or acute suicidal risk (MINI interview; see DSM5 TRE screening)

• High scores (> 5) on the Screening Eating Disorder Examination Questionnaire

• Current shift work

• >5 kg weight change within 3 months

• Pregnancy

• Breastfeeding

• Uncorrected hypo or hyperthyroidism

  * diabetes type 1

• Gastrointestinal conditions impairing nutrient absorption

• Medications contraindicated for fasting, including clozapine, glucose-lowering medications, diabetes-related injections, requiring food early morning or late evening, corticosteroids.

De-identified data will be available at OSF post-study.

Within one year of study completion, if ethics board approves.

Available through OSF.