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

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.