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Objectives The cognitive-protective effects related to the consumption of a variety of fruits are supported by several intervention studies. This systematic review and meta-analysis compared the magnitude of effects following chronic (≥1 week) consumption of frozen, freeze-dried powder including extracts and juices of fruits, covering berries, cherries and citrus, on cognition and mood in adults. Methods PubMed, Web of Science, Scopus, and psycARTICLES were searched from inception until February, 2021. Inclusion criteria were randomised controlled trials assessing memory, executive function, psychomotor speed, mood and mini mental state examination in adult participants ≥18 years of age. Cognition was tested by global or domain specific tasks. Results Out of 13,861 articles identified, 16 papers were included; 11 studies provided suitable data for meta-analysis. Fourteen studies reported improvement or trend for improvement in cognition, five studies assessed mood and one study supplementing grape juice found trend for mood improvement. From the meta-analysis, cherry juice supplementation was suggested to improve psychomotor speed by −0.37 of standardised mean difference (95% CI [−0.74, 0.01]) in reaction time (P = 0.05). Conclusions The meta-analysis did not sufficiently support a role for fruits or fruit forms to improve cognition and mood.

In the original publication, a study supplementing orange juice by Morand, et al., 2011 (France) was incorrectly reported for the diastolic blood pressure (DBP) outcome. We originally reported no improvement in DBP as results were reported as least square means, when actually Morand and investigators found a significant improvement in DBP by orange juice compared to placebo. The study should have been reported in Table 1 as “significant improvement compared to the control”, and therefore there should be 11 interventions in the review reporting improvements on blood pressures. We include here an updated forest plot of the citrus juice group, that includes the correct findings of the Morand study investigating the outcome of DBP (Fig. 6). In our updated meta-analysis there was no significant improvement in DBP by the citrus juice interventions compared to the control. The I2 test suggested significant substantial heterogeneities for citrus juice group investigating the effects on DBP (I2 = 83%, P