Project Results

Data analysis is complete! See a the project's abstract below, which is taken from my MS thesis, for a more technical description of the results. 

We had some interesting results, such that none of our findings were statistically significant. I say interesting because they are contrary to what we predicted, such that one night of partial sleep deprivation did not affect disordered eating in this sample of adult females. In other words, short-term, partial sleep loss may not affect disordered-eating behaviors, as has been suggested in previous research. 

Despite our lack of significant findings, this study adds to our understanding of the relation between sleep loss and disordered eating, as this is one of two research studies that used an experimental manipulation of sleep deprivation to examine the effects on disordered eating. 

To contributors reading this - I know that these results may seem disappointing (I know I've felt disappointed at times); however, my hope is that this study will still set the stage for more studies examining the link between sleep disturbances and eating disorder symptoms. Our study likely had limited statistical power due to unforeseen methodological issues and we used a representative sample of adult females. Future studies may benefit from sampling participants with current eating disorder symptoms and/or diagnosed eating disorders and from using a larger sample with a crossover design (vs. parallel group design). Unfortunately, science is filled with research studies that have null findings and that have not turned out the way the researchers expected. I believe the important thing to do is continue to think critically, ask questions, accept that we can't make perfect predictions, and admit our mistakes. 

If you have questions regarding these results, feel free to message me or post on project's the discussion board! Thank you!!

-- Nicole 

ABSTRACT

Previous research has linked sleep disturbances with disordered eating. Studies have also shown that one night of partial sleep deprivation causes increases in food intake and appetite disturbances. However, the effects of sleep deprivation on disordered eating and subjective appetite are unclear as research has yet to examine the effects of one night of partial sleep deprivation (less than or equal to 4 hours of sleep) on disordered eating in a representative adult female sample. Adult, female participants (N=40) completed eligibility and baseline measures reporting medical conditions, eating disorder symptoms, sleep disturbances, depressed mood, and anxiety symptoms. Participants were randomized to either the sleep-deprived condition (~50% of their average sleep duration) or the habitual-sleep condition (~100% of their average sleep duration). The morning after the sleep condition, participants completed self-report appetite and disordered eating measures before and after consuming a standardized test meal and later that evening. The following statistical analyses, adjusted for multiple comparisons (p<0.002), found no significant group differences: independent samples t-tests (outcome: pre-meal appetite, disordered eating, and test-meal consumption), multivariate analyses of variance (MANOVAs) (outcome: pre- and post-meal area under the curve [AUC] disordered eating and appetite), repeated measures ANOVAs (time X group; outcome: pre- and post-meal appetite and disordered eating), analyses of covariance (ANCOVAs; controlling for pre-meal ratings; outcome: disordered eating at follow-up), and Pearson’s chi-square tests (outcome: follow-up appetite and disordered eating). Despite finding no support for the effect of sleep deprivation on disordered eating, this study extends previous research as a novel study using the experimental manipulation of sleep deprivation to examine its effects on disordered eating.

About This Project

Research studies have linked characteristics of eating disorders (e.g., binge eating, extreme dieting) with sleep disturbances (e.g., sleep loss from difficulty falling and staying asleep). This study will test how one night of sleep deprivation affects eating behaviors, including food consumption and disordered eating. This study aims to identify novel risk factors of disordered eating, with hopes to inform interventions for people with eating disorders.

Ask the Scientists

What is the context of this research?

- Disordered eating characterizes eating disturbances that range from non-problematic eating to eating disorders, which indicate extreme eating disturbances.

- Up to approximately 3% of the general population may be diagnosed with an eating disorder throughout their lifetime.

- Eating disorders are serious mental illnesses, which are linked to elevated rates of mortality and suicide.

- It is crucial to understand predictors of disordered eating for effective early intervention strategies to prevent the onset or curtail the progression of an eating disorder.

- Research supports an association between sleep problems and disordered eating.

- No studies have directly tested sleep deprivation as a risk factor for disordered eating.

What is the significance of this project?

- This is the first study to test the effects of sleep deprivation on disordered eating, which will determine the short-term impact of sleep deprivation on disordered eating behaviors, including binge eating, vomiting, and exercising.

- This study will pave the way for future studies, involving objective measures of sleep (actigraphy watches) and appetite hormones, as well as prospective designs to understand the long-term impact of sleep deprivation on disordered eating.

- It is critical to understand novel risk factors of disordered eating to improve treatments of eating disorders. In fact, studies report that current treatments have high rates of relapse, suggesting the need for improved treatments.

What are the goals of the project?

The goals of this study are to examine how one night of sleep deprivation influences eating patterns the next day. We will explore if sleep deprivation leads to:

1. Greater urges to binge eat, vomit, and exercise?

2. Greater consumption of a test meal?

3. Greater feelings of hunger and desire to eat before the test meal?

And,

4. Do depression and anxiety affect the impact of sleep deprivation on disordered eating?

Sixty adult women will either sleep about 8 hours or about 4 hours (sleep deprived) before visiting our lab to report disordered eating urges and appetite after consuming an english muffin and a nutritional shake. Participants will report disordered eating behaviors the night after the lab visit.