The Biobehavioral Impact of Diet Quality on Affect and Craving

The current study experimentally investigates whether reducing highly processed (HP) foods (defined in this study as foods high in added sugars) leads to, psychological and / or behavioral indicators of withdrawal. The following hypotheses are tested:

1. To test the hypothesis that reducing highly processed food intake will result in higher daily reports of physical (e.g. headaches), cognitive (e.g. difficulty concentrating), and affective (e.g., irritability) withdrawal symptoms).
2. To test the hypothesis that reducing highly processed food intake will result in increased negative affect (e.g., irritability, depression) as indicated by and psychological (self - reported distress ratings; daily emotion / mood reports) measures.
3. To test the hypothesis that reducing highly processed food intake will result in increased food craving as indicated by psychological (self - report craving ratings; daily craving report) measures.

All activities are completed remotely. Participants complete 4 phone appointments with a trained member of the research team. Daily questionnaires and ecological momentary assessments are completed at home between phone appointments. The initial call signs electronic consent and gets baseline measurements (questionnaires). After the initial call, participants start an active assessment period (pre / post dietary change assessments). Pre-dietary change includes at home questionnaires and ecological momentary assessments while eating a typical diet. It also includes the second phone appointment. Post-dietary change includes at home questionnaires and ecological momentary assessments while consuming 3 days of food portions lower in highly processed foods. Participants will complete a food journal on the remaining 2 days of post - dietary change assessment to report what food they ate. Post - dietary change also includes the third phone appointment. The second and third phone appointments each include computer tasks and questionnaires. The final phone appointment is a debriefing interview. Participants planning to continue eating a healthier diet may also be invited to complete a follow-up period, which involves answering a short questionnaire at home every other day for two weeks. 7 individuals had in-person data collected prior to the pandemic requiring a shift to virtual data collection.


Eligibility Criteria:
Inclusion Criteria:

* Age 25 to 40
* Access to internet, private computer and smart phone
* Overweight (self-report BMI above 25.0)
* Moderately or Highly motivated to eat a healthier diet
* Mild, moderate or severe levels of addictive like eating (2 or higher on the Yale Food Addiction Scale)
* Fluent in english
* Willing to follow dietary guidelines provided by study team and eat only provide food for 3 days. Willing to delay dietary change until instructed to do so

Exclusion Criteria:

* Use of nicotine in the past month, cannabis in the past month, or illicit drugs in the past 6 months
* Weight fluctuation of 20+ pounds in the last 3 months
* Attempted weight loss using a formal weight loss program (e.g. weight watchers) in the last month
* Prior weight loss surgery (e.g. bariatric surgery)
* Medications or medical conditions that may impact study results such as medications that impact appetite, heart rate, or reward functioning (e.g. taking synthroid or has diabetes)
* Current major psychiatric diagnoses (e.g., bipolar, schizophrenia, substance use disorder, eating disorder)
* A diagnosis of a restrictive eating disorder in the past 5 years (anorexia nervosa, bulimia nervosa, purging disorder)
* Significant dietary restrictions (e.g. allergies, veganism)
* currently pregnant, breastfeeding, trying to get pregnant, or within 6 months of giving birth