The Acute Effects of Blueberries on Cognition and Mood in the Postpartum
- Conditions
- MoodParentsHealthy
- Interventions
- Dietary Supplement: Blueberry drinkDietary Supplement: Placebo drink
- Registration Number
- NCT06402916
- Lead Sponsor
- University of Reading
- Brief Summary
Blueberries are an excellent source of natural substances (flavonoids) with well-documented health benefits. Previous research has shown that consuming a serving of blueberries can improve mood in children, healthy young adults, and young adults with depressive symptoms. These results are consistent with a growing body of evidence from human and animal studies indicating that blueberries can have a beneficial effect on brain function and mental health. The postpartum period represents a challenging period whereby mood disorders such as postpartum depression become increasingly prevalent, in addition to this, mothers and fathers often report poorer cognition during this time. Therefore, it is of interest to explore whether acute blueberry supplementation can benefit mood and cognition for parents during this sensitive time.
The aim of the present study is to examine whether consuming a drink containing powdered blueberries can improve mood and cognition in parents in the 0-6 month postpartum. The design follows a randomised, double blind, placebo controlled cross over design. Participants will be invited to take part in an in-person study investigating a fruit drink on mood and cognition. Participants will come to the Nutrition-cognition lab at the Psychology department at the University of Reading for a screening session, after providing informed consent, participants will return a week later to attend a 3-hr visit during which they will receive either a blueberry or placebo drink and complete computer tasks and standardised questionnaires. Participants will then return a week later and complete the same procedure, consuming the other intervention drink.
- Detailed Description
The design follows a randomised, double blind, placebo controlled cross over design. Participants will be recruited via social media, posters in the local area, and through word of mouth and email advertisements and will be invited to take part in an in-person study investigating a fruit drink on mood and cognition. Participants will come to the Nutrition-cognition lab at the Psychology department for a screening session, during the session the study will be explained by the researcher and the participant will receive the participant information sheet. If the participant is eligible and wants to take part, they will sign the consent form. Data collected at screening will include age, ethnicity, highest level of education, marital status, specific diet, income, employment, physical illnesses, psychological diagnosis, regular medications, how old their infant is, infant gender, previous children, and age of other children as well as postnatal depression, postnatal anxiety (mother's sample only), state anxiety (father's sample only) a food frequency questionnaire and anthropometric measures to determine body mass index (BMI). Participants will then complete practice versions of the cognitive tests. Office for National Statistics recommendations will be used when collecting participants demographic details of ethnicity and income.
A week later, upon arrival at the Nutrition Cognition Lab (approximately 9am) participants will be asked to note what they had for breakfast (to ensure they have the same breakfast next week for standardisation) and a researcher will ask whether they have followed the pre-session restrictions prior to coming in for the visit (see below). Participants will then complete the mood and cognitive questionnaires (listed below) and have their blood pressure taken (duration 30 min). The order of questionnaires and cognitive tasks will be kept the same throughout the study. Participants will then be randomly allocated to consume one of two interventions (blueberry drink or a similarly flavoured placebo drink). The blueberry drink consists of 46g freeze dried wild blueberry powder mixed with 250ml water, the placebo drink contains 46g placebo powder matched for sugars and vitamin C content of the blueberry powder, mixed with 250ml water. The tests will then be repeated 2 hours after consuming the drink. Participants will be able to leave the lab and have free time for the 2hrs in between testing. During the procedure, we will also request that if participants bring their infant on the day, that they also bring a partner (friend, relative or parent of infant) to care for their infant during this time so to not distract the participant during the mood and cognitive tasks. Participants will then return to the lab a week later and carry out the same procedure, though consuming the other intervention drink. After the study has been completed, participants will be debriefed and given the opportunity to ask any questions. Participants will also be reminded of their right to withdraw their data from the study if they wish. Helplines and support web links will be provided to all participants as well as encouragement for participants to contact their GP should they wish to seek support. Helplines and weblinks include Samaritans UK and PANDAS Foundation. Weblinks to NHS, MIND and the Association for Postnatal Illness.
Pre-session restrictions: Twenty-four hours before the first and second test sessions, all participants will be advised to follow a low flavonoid diet which will be advised by an information sheet provided by the researchers upon sign-up. These restrictions will be implemented as a control measure so that other dietary flavonoids do not interfere with the results of the study and researchers will check adherence to restrictions prior to the first sitting of the study. Within this 24-hour period, participants will also be asked not to drink alcohol, caffeine or take recreational drugs. Participants will also be asked to refrain from exercise and food 2 hours before and following the intervention (water will be allowed) to avoid confounding effects.
Recruitment & Eligibility
- Status
- NOT_YET_RECRUITING
- Sex
- All
- Target Recruitment
- 60
- Participants must be a biological mother or father to an infant aged 0-6 months.
- Have a good understanding of English language
- Allergic to blueberries or any other Vaccinium species
- Participation in other interventional studies within the last month
- Participants with cancer, or conditions affecting the liver, heart or kidneys due to unknown effects on flavonoid metabolism
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Blueberry drink Blueberry drink 46g freeze-dried wild blueberry (Vaccinium angustifolium) powder mixed with 250 ml water. Placebo drink Placebo drink 46g placebo powder matched for macronutrients, color, and flavor mixed with 250 ml water.
- Primary Outcome Measures
Name Time Method Mean current affect 2 hours post ingestion Assessed using scores from the Positive and Negative Affect Scale. This questionnaire has 20 items that describe some feelings and emotions. The participant needs to mark how much they are experiencing these feelings on a scale from 1-5. This produces scores of Positive Affect and Negative Affect; higher scores reflect higher positive or negative mood, respectively.
- Secondary Outcome Measures
Name Time Method Verbal memory 2 hours post ingestion Assessed using the Rey Auditory Verbal Learning Test.
Mean subjective mood scores 2 hours post ingestion Immediate mood scale-This questionnaire contains 22 items developed to assess dynamic components of mood. Participants are asked to rate their current mood state on a continuum using 7-point Likert scales (e.g., happy-sad, distracted-focused, sleepy-alert). For each item, an integer score between 1 and 7 is derived. The total score for this scale is the sum of the scores on all 22 items.
Blood pressure 2 hours post ingestion Resting systolic and diastolic blood pressure will be taken with an ambulatory blood pressure monitor. Measurements will be taken on participants left arm and the mean of three consecutive measurements will be calculated.
Sustained attention and executive functioning 2 hours post ingestion Assessed with the Modified Attention Network Task with accuracy and reaction time as outcome measures.
Visuospatial working memory 2 hours post ingestion Measured using the Visuospatial n-back with accuracy and reaction time as outcome measures.
Mean state anxiety 2 hours post ingestion Assessed using scores from the State-Trait Anxiety Inventory- State scale. Higher scores indicate higher levels of anxiety. This questionnaire is a measure of state and trait anxiety containing 40 items in total (20 for trait; 20 for state). Only the state scale (20 items) will be used in current research to measure situational anxiety. Participants are asked to agree or disagree with anxiety-related statements on a scale of 1-4
Mean subjective feelings 2 hours post ingestion These consists of 16 dimensions of mood: Slow-Quick Witted, Tense-Relaxed, Attentive-Dreamy, Incompetent-Proficient, Happy-Sad, Antagonistic-Friendly, Interested-Bored, Withdrawn-Social. The participant is required to mark, on a line to what extent the described state is appropriate to them at that moment in time. The individual responses from the 16 mood scales are combined to make three affective dimensions of alertness, contentment, and calmness.