ABSORB (Amount of Blueberries So Older Adults Reap Benefits)

Acute Bioavailability of Berry Flavonoids and Impact on Inflammatory Biomarkers in Older Adults With Minor Depressive Symptoms: A Pilot Study

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05937165

Enrollment

Registered

2023-07-10

Start date

2023-10-31

Completion date

2024-11-25

Last updated

2025-12-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Depressive Symptoms, Aging

Brief summary

This randomized, cross-over, pilot study aims to compare preliminary impact of a standard dose of blueberry powder (24 g) vs a higher dose (48 g) on the bioavailability of flavonoids and inflammatory biomarkers in older adults with minor levels of depressive symptoms.

Detailed description

Blueberries are a rich source of anti-oxidants and dietary fiber, and are recommended to consume as a part of a healthy diet. Regular consumption of blueberries as a source of dietary antioxidants may be an effective way to lower inflammation in older adults, who commonly have higher levels of inflammatory markers. However, older adults typically have a decreased efficiency of nutrient absorption and may need a higher dose of blueberries to absorb enough of the flavonoids needed to reap their benefits on inflammation. Thus, it is important for preliminary studies to pre-determine an appropriate dose of blueberry flavonoids specifically for older adults. This study aims to evaluated the preliminary impact of freeze-dried blueberry powder consumption on flavonoid bioavailability and inflammatory biomarkers in older adults. This will be an individual-level, unblinded, randomized, cross over pilot study in 5 older adults with minor levels of depressive symptoms. Eligible participants will collect a 24 hour urine sample, and then come in for the baseline assessments and provide a blood sample. Next they will be randomized to consume either the higher dose (48 g/day, equivalent \ 2 cups of fresh blueberries) or the lower dose (24 g/day, equivalent \ 1 cup of fresh blueberries) for 3 days. After 3 days they will begin collecting a 24 hour urine sample, and come in to repeat the baseline assessments and provide a blood sample. After a two week wash out period, participants will repeat the same baseline and follow-up assessments while consuming the other powder.

Interventions

OTHERFreeze-dried Blueberry Powder

Three day consumption of two doses of freeze-dried blueberry powder

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

OTHER

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

65 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* Men and women aged 65 years and older * Minor levels of depressive symptoms (center for epidemiological studies depression scale, ≥4 and \<16 points)

Exclusion criteria

\*: * Unwilling to follow the study protocol * Cognitive impairment (assessed via the telephone Montreal Cognitive Assessment) defined as individuals scoring \<19) * Self-reporting a history of major depression, bipolar, schizophrenia, or other psychotic or neurologic disorders * Self-reporting of history gastro-intestinal diseases/conditions e.g., of bowel resection, inflammatory bowel disease/syndrome, Celiac disease * Self-reporting immune disorders, e.g., rheumatoid arthritis, cancer, and other immunocompromising conditions * Self-reporting history of type 1 or type 2 diabetes * Self-reporting any history of substance or alcohol use disorder * Allergy to blueberries * Self-reporting use of anti-inflammatory (e.g., fish oil or non-steroidal anti-inflammatory drugs) or immune-suppressant drugs * Are excessive tea or coffee consumers (e.g., \>3 cups/day) * Recent and consistent use of antibiotics * Currently taking or advised during the intervention to take anti-depressants * Current homicidal or suicidal ideation (assessed via the P4 Suicidality Screener * All deviations must be approved by the study sponsor

Design outcomes

Primary

Measure	Time frame	Description
Urinary Flavonoid Biomarkers	Baseline and Day 3 of intervention	Change in total flavonoid metabolites found in the urine. The values for the metabolites represent the relative abundance of each metabolite, rather than absolute quantification, with higher values reflecting higher levels of total flavonoid metabolites in the urine.
Inflammatory Biomarker C-reactive Protein	Baseline and Day 3 of intervention	Change in serum C-reactive Protein

Secondary

Measure	Time frame	Description
Inflammatory Biomarker Tumor Necrosis Factor Alpha	Baseline and Day 3 of intervention	Change in tumor necrosis factor alpha
Inflammatory Biomarker Interleukin 6	Baseline and Day 3 of intervention	Change in interleukin 6
Inflammatory Biomarker Interferon Gamma	Baseline and Day 3 of intervention	Change in serum interferon gamma

Countries

United States

Participant flow

Participants by arm

Arm	Count
Freeze-dried Blueberry Powder (Standard Dose Then Higher Dose) Consumption of 24 g of freeze dried blueberry powder for 3 consecutive days and then consumption of 48 g of freeze dried blueberry powder for 3 consecutive days, separated by a washout.	3
Freeze-dried Blueberry Powder (Higher Dose Then Standard Dose) Consumption of 48 g of freeze dried blueberry powder for 3 consecutive days and then consumption of 24 g of freeze dried blueberry powder for 3 consecutive days, separated by a washout.	3
Total	6

Withdrawals & dropouts

Period	Reason	FG000	FG001
Overall Study	Withdrawal by Subject	0	1

Baseline characteristics

Characteristic	Freeze-dried Blueberry Powder (Standard Dose Then Higher Dose)	Freeze-dried Blueberry Powder (Higher Dose Then Standard Dose)	Total
Age, Continuous	69 years STANDARD_DEVIATION 4	76 years STANDARD_DEVIATION 5	73 years STANDARD_DEVIATION 5
Depressive Symptom Severity	3.0 points STANDARD_DEVIATION 2	4.3 points STANDARD_DEVIATION 3.1	3.7 points STANDARD_DEVIATION 2.4
Race (NIH/OMB) American Indian or Alaska Native	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Asian	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Black or African American	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) More than one race	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants	0 Participants	0 Participants
Race (NIH/OMB) White	3 Participants	3 Participants	6 Participants
Region of Enrollment United States	3 Participants	3 Participants	6 Participants
Sex: Female, Male Female	2 Participants	3 Participants	5 Participants
Sex: Female, Male Male	1 Participants	0 Participants	1 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk
deaths Total, all-cause mortality	0 / 5	0 / 6
other Total, other adverse events	0 / 5	0 / 6
serious Total, serious adverse events	0 / 5	0 / 6