Mild cognitive impairment (MCI) represents an intermediate stage between normal cognitive function and dementia. Delaying the onset or progression of dementia has therefore become a key research priority. Although previous studies have examined the individual effects of fish oil or pine bark extract on cognitive decline, their findings remain inconclusive. In this study, we compared the effects of fish oil alone versus fish oil combined with pine bark extract on cognitive function and the oxidative status in patients with MCI. Participants aged 55–75 years with MCI were enrolled in a 24-week, double-blind, parallel-group trial, and they were randomly assigned to either a fish oil group (F group, n = 14), which received one fish oil capsule (350 mg eicosapentaenoic acid and 250 mg docosahexaenoic acid) and one placebo capsule, or a fish oil combined with pine bark extract group (F+P group, n = 14), which received one fish oil capsule and one pine bark extract capsule (100 mg). Compared to the baseline, the F group showed a significant decrease in Clinical Dementia Rating scores and a significant increase in Mini-Mental State Examination scores. In the subdomain analysis of the Cognitive Abilities Screening Instrument, the F group demonstrated a significant increase in the drawing score, whereas the F+P group showed a significant increase in the short-term memory score. Regarding the antioxidant status, compared to the baseline, the F group exhibited a significant increase in plasma thiobarbituric acid reactive substance (TBARS) levels and erythrocytic superoxide dismutase activity, whereas catalase (CAT) activity significantly decreased. After 24 weeks, plasma TBARS levels showed no significant change, while CAT activity was significantly higher in the F+P group than in the F group. These findings suggest that combined supplementation with fish oil and pine bark extract may be associated with potential improvements in short-term memory performance and antioxidant status in middle-aged and older adults with MCI, although the results should be interpreted cautiously.
Hsiao et al. (2026) studied this question.