ABSORB (Amount of Blueberries So Older Adults Reap Benefits)

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