Brief
Pilot study links daily blueberry intake to gut changes and mood trends in seniors
Researchers observed subtle gut‑microbiome shifts and a non‑significant mood improvement among seniors who consumed blueberry powder for three months.
By Felo News Desk · Published
A pilot study involving 18 adults aged 65 and older examined whether daily consumption of blueberry powder could affect gut bacteria and depressive symptoms. Participants took either 48 g of blueberry powder (about two cups of fresh berries) or a matching placebo for three months, with researchers measuring gut‑microbial composition, short‑chain fatty acids, and mood questionnaires before and after the trial.
What happened
The double‑blind, randomized, parallel‑arm trial enrolled 18 participants, most of whom were women and predominantly white. The placebo group comprised eight participants with a mean age of 75 ± 6 years, while the blueberry group included ten participants with a mean age of 71 ± 4 years. Over the three‑month period, researchers performed metagenomic sequencing on stool samples to assess microbial species and gene abundance, and used liquid chromatography/mass spectrometry to quantify fecal short‑chain fatty acids.
What the reports add
According to ScienceDaily, the blueberry group showed a greater and more consistent reduction in depressive‑symptom scores than the placebo group, though the difference did not reach statistical significance. The study also reported subtle changes in genes linked to microbial enzymes that are relevant to depression. No significant differences were found in short‑chain fatty‑acid levels between the two groups.
What was said
"Fiber and anthocyanins in blueberries have potential to modify the gut microbiome and metabolites that are relevant to depression in older adults," said lead author Courtney L. Millar, PhD, assistant scientist II at Hebrew SeniorLife's Hinda and Arthur Marcus Institute for Aging Research and assistant professor of medicine at Beth Israel Deaconess Medical Center and Harvard Medical School, as quoted by ScienceDaily.
How it came about
The investigation was motivated by growing interest in the gut‑brain axis and the role of diet in mental health. Researchers recruited physically inactive seniors experiencing mild depressive symptoms to explore whether a nutritionally rich food—blueberries, known for their fiber and anthocyanin content—could produce measurable changes in gut microbes and mood. The pilot’s findings are intended to inform larger, definitive trials.
Key facts
- The study enrolled 18 participants aged 65 and older, 10 receiving blueberry powder and 8 receiving placebo. (sciencedaily.com)
- Participants consumed 48 g of blueberry powder daily for three months. (sciencedaily.com)
- Depressive‑symptom scores declined more in the blueberry group, but the difference was not statistically significant. (sciencedaily.com)
- Metagenomic sequencing revealed subtle changes in gut‑microbial genes linked to depression. (sciencedaily.com)
- No significant change in short‑chain fatty‑acid levels was observed between groups. (sciencedaily.com)
Sources
- [1] sciencedaily.com — originally reported as “Eating blueberries every day may have a surprising effect on your mood”
