Effects of chronic consumption of specific fruit (berries, cherries and citrus) on cognitive health: a systematic review and meta-analysis of randomised controlled trials

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.

Acute cognitive performance and mood effects of coffee berry and apple extracts: A randomised, double blind, placebo controlled crossover study in healthy humans

Background: Polyphenols from coffee berry (chlorogenic acid) and apple (flavanol) have been shown to improve mood and increase cerebral blood flow in healthy humans. These effects may underpin the cognitive effects of polyphenols seen previously.Objective: The aim of the present paper was to extend previous research by investigating the effects of coffee berry at high and low doses when combined with apple extract on cognitive performance and mood.Design: This randomised, double-blind, placebo controlled, crossover trial included 46 healthy males and females,18-49 years of age (mean age 23 years),consuming: 1100 mg coffee berry extract, 1100 mg coffee berry extract plus 275 mg apple extract, 100 mg coffee berry extract plus 275 mg apple extract or placebo on 4 separate occasions, completing cognitive and mood assessments pre-dose and then again at 1-, 3- and 6 hrs post-dose.Results: Analysis revealed a consistent pattern of alerting effects following 1100 mg coffee berry extract. Limited effects on cognitive function were observed. Specifically, faster peg and ball performance (executive function) was observed following 1100 mg coffee berry plus apple extract and accuracy on the Rapid Visual Information Processing (RVIP) task increased on the third of four repetitions following 1100 mg coffee berry alone. Interestingly, more false alarms on RVIP were observed following the same intervention.Conclusions: In line with previous findings, 1100 mg coffee berry engendered increased arousal. The absence of effects on mood when an apple extract was added, and the potential for the low dose of caffeine within the coffee berry to act synergistically with polyphenols, raise interesting future avenues of research.Abbreviations: Cognitive demand battery (CDB), Profile Of Mood States (POMS), Visual Analogue Scale (VAS), Rapid Visual Information Processing (RVIP).

One-Carbon Metabolites, B Vitamin Intake, Apolipoprotein E Genotype, and Their Interactive Effects on Cognitive Performance: Secondary Outcomes of the REACH Cohort

Objectives

To investigate associations between one-carbon metabolites and cognitive performance in older adults, and to examine the interactive effects of B vitamin intake, apolipoprotein E genotype, and one-carbon metabolites on cognition.

Methods

Three hundred and thirteen healthy older men and women (65–74 years, 65% female) were included in this secondary analysis of the REACH cohort. Cognitive performance was assessed by the Computerised Mental Performance Assessment System (COMPASS). Fasting plasma one-carbon metabolites (betaine, choline, cysteine, dimethylglycine, glycine, homocysteine, methionine, S-adenosylmethionine, serine) were quantified by ultra high performance liquid chromatography with tandem mass spectrometry, and four-day food records were analyzed for nutrient intake. Presence of the

apolipoprotein E ε4 allele was measured by polymerase chain reaction amplification. Linear regression models were adjusted for age, sex, batch effects, education level, physical activity, energy intake and supplement use. Interaction terms were fit between continuous (metabolites) and categorical (quartiles of B vitamin intake or metabolites not fit as the main independent variable, presence of apolipoprotein ε4 allele) variables.

Results

Higher glycine concentrations were associated with better global cognitive performance (β = 1.340, P = 0.017), episodic memory (β = 1.396, P = 0.016) and location learning (β = 1.394, P = 0.027) in linear regression models, although this relationship was not apparent in participants with higher choline concentrations or the apolipoprotein ε4 genotype (interaction, P < 0.05). Conversely, the apolipoprotein ε4 genotype and higher vitamin B12 intake both attenuated the inverse association between Hcy and cognition across several domains of cognitive performance (interaction, P < 0.05).

Conclusions

The relationship between cognitive performance and one-carbon metabolites, notably glycine and homocysteine, is modified by vitamin B12 intake, apolipoprotein E genotype, and status of inter-connected metabolites. These findings point towards the need for a personalized approach to dietary interventions which protect against age-related cognitive decline.

Funding Sources

This work was supported by the Health Research Council of New Zealand and AgResearch Ltd.

Dietary Patterns, Their Nutrients, and Associations with Socio-Demographic and Lifestyle Factors in Older New Zealand Adults

Dietary patterns analyse combinations of foods eaten. This cross-sectional study identified dietary patterns and their nutrients. Associations between dietary patterns and socio-demographic and lifestyle factors were examined in older New Zealand adults. Dietary data (109-item food frequency questionnaire) from the Researching Eating, Activity and Cognitive Health (REACH) study (n = 367, 36% male, mean age = 70 years) were collapsed into 57 food groups. Using principal component analysis, three dietary patterns explained 18% of the variation in diet. Dietary pattern associations with sex, age, employment, living situation, education, deprivation score, physical activity, alcohol, and smoking, along with energy-adjusted nutrient intakes, were investigated using regression analysis. Higher 'Mediterranean' dietary pattern scores were associated with being female, higher physical activity, and higher education (p < 0.001, R2 = 0.07). Higher 'Western' pattern scores were associated with being male, higher alcohol intake, living with others, and secondary education (p < 0.001, R2 = 0.16). Higher 'prudent' pattern scores were associated with higher physical activity and lower alcohol intake (p < 0.001, R2 = 0.15). There were positive associations between beta-carotene equivalents, vitamin E, and folate and 'Mediterranean' dietary pattern scores (p < 0.0001, R2 ≥ 0.26); energy intake and 'Western' scores (p < 0.0001, R2 = 0.43); and fibre and carbohydrate and 'prudent' scores (p < 0.0001, R2 ≥ 0.25). Socio-demographic and lifestyle factors were associated with dietary patterns. Understanding relationships between these characteristics and dietary patterns can assist in health promotion.

Effects of chronic consumption of specific fruit (berries, citrus and cherries) on CVD risk factors: a systematic review and meta-analysis of randomised controlled trials

Purpose

This review aims to compare the magnitude of the effects of chronic consumption of fruits; specifically berries, citrus and cherries on cardiovascular disease (CVD) risk factors.

Methods

PubMed, Web of Science, Scopus, and psycARTICLES were searched from inception until January 2020. Forty-five chronic (≥ 1 week) randomised controlled trials assessing CVD risk factors including endothelial (dys)function, blood pressure (BP), blood lipids and inflammatory biomarkers were included.

Results

Investigated interventions reported improvements in endothelial function (n = 8), inflammatory biomarkers and lipid status (n = 14), and BP (n = 10). Berries including juice of barberry, cranberry, grape, pomegranate, powder of blueberry, grape, raspberry and freeze-dried strawberry significantly reduced SBP by 3.68 mmHg (95% CI − 6.79 to − 0.58; P = 0.02) and DBP by 1.52 mmHg (95% CI − 2.87 to − 0.18, P = 0.04). In subgroup analysis, these associations were limited to cranberry juice (SBP by 1.52 mmHg [95% CI − 2.97 to − 0.07; P = 0.05], DBP by 1.78 mmHg [95% CI − 3.43 to − 0.12, P = 0.04] and cherry juice (SBP by 3.11 mmHg [95% CI − 4.06 to − 2.15; P = 0.02]). Berries also significantly elevated sVCAM-1 levels by 14.57 ng/mL (85% CI 4.22 to 24.93; P = 0.02).

Conclusion

These findings suggest that supplementing cranberry or cherry juice might contribute to an improvement in blood pressure. No other significant improvements were observed for other specified fruits. More research is warranted comparing different classes of fruit and exploring the importance of fruit processing on their cardiovascular-protective effects.

Electronic supplementary material

The online version of this article (10.1007/s00394-020-02299-w) contains supplementary material, which is available to authorized users.