Increased habitual flavonoid intake predicts attenuation of cognitive ageing in twins

Abstract

Background Although the pathophysiology of cognitive decline is multifactorial, and modifiable by lifestyle, the evidence for the role of diet on cognitive function is still accumulating, particularly the potentially preventive role of constituents of plant-based foods. Methods We aimed to determine whether higher habitual intake of dietary flavonoids, key components of plant-based diets, were associated with improved cognition and medial temporal lobe volumes using three complementary approaches (longitudinal, cross-sectional and co-twin analyses). In 1126 female twins (n=224 with a 10-year follow-up of diet and cognition data) aged 18–89 years, habitual intakes of total flavonoids and seven subclasses (flavanones, anthocyanins, flavan-3-ols, flavonols, flavones, polymeric flavonoids (and proanthocyanidins separately)) were calculated using validated food frequency questionnaires. Cognition was assessed using the Cambridge Neuropsychological Test Automated Battery test. Hippocampal volumes were measured in a subset using magnetic resonance imaging (16 monozygotic-twin pairs). Statistical models were adjusted for a range of diet and lifestyle factors. Results Higher intakes of flavanones (tertile (T)3-T1=0.45, 95%CI 0.13,0.77; p=0.01) and anthocyanins (T3-T1=0.45, 95%CI 0.08,0.81; p=0.02) were associated with improvements in age-related cognition score over 10 years. In cross-sectional analysis higher intake of flavanones (T3-T1= 0.12, 95% CI 0.02, 0.21; p=0.02) and proanthocyanidins (T3-T1= 0.13, 95% CI 0.02, 0.24; p=0.02) were associated with improved paired-associates learning. Higher intake of anthocyanins was significantly associated with improved executive function (T3-T1= −0.52, 95% CI 0.19, 0.84; p=0.001) and with faster simple reaction times (T3-T1= −18.1, 95% CI −35.4, −0.7; p=0.04). In co-twin analysis, those with higher anthocyanin (2.0%, p=0.01) and proanthocyanidin (2.0%, p=0.02) intakes at baseline had the largest left hippocampal volumes after 12 years. Conclusion Small increases in habitual intake of flavonoid-rich foods (containing anthocyanins, flavanones and proanthocyanidins; equivalent to approximately two servings of oranges and blueberries per day) over long time periods have the potential to attenuate cognitive ageing.

Dietary (Poly)phenols and Cognitive Decline: A Systematic Review and Meta‐Analysis of Observational Studies

“…A total of 1823 studies were identified through the search strategy ( Figure 1 ). Out of these, after examination of the title ( n = 1303) and abstract ( n = 521) and full texts ( n = 487), 37 articles [ 15–51 ] were included in this review. The main characteristics of the included studies are presented in Table S2, Supporting Information.…”

“…[ 19 ] Among more recent studies, an investigation of the TwinsUK study recruited and followed up for about 10 years 1126 female twins (aged 18–89 years), tested for cognitive function with the Cambridge Neuropsychological Test Automated Battery (CANTAB) tests: in the cross‐sectional analysis, higher compared to lower intake of flavanones (T3 vs T1 cognitive score = 0.12, 95% CI: 0.02, 0.21; p = 0.02) and proanthocyanidins (T3 vs T1 cognitive score = 0.13, 95% CI: 0.02, 0.24; p = 0.02) was associated with improved paired‐associates learning, and higher intake of anthocyanins was significantly associated with improved executive function (T3–T1 cognitive score = −0.52, 95% CI: 0.19, 0.84; p = 0.001) and with faster simple reaction times (T3–T1 cognitive score = −18.1, 95% CI: −35.4, −0.7; p = 0.04); when assessed longitudinally, higher intake of flavanones (T3 vs T1 age‐related cognition score = 0.45, 95% CI: 0.13, 0.77; p = 0.01) and anthocyanins (T3 vs T1 age‐related cognition score = 0.45, 95% CI: 0.08, 0.81; p = 0.02) were associated with improvements in age‐related cognition score over 10 years. [ 20 ] Finally, a recently published study from the Rush Memory and Aging Project, including 961 participants (aged 60–100 years) and followed for an average of 6.9 years annually, tested for cognitive performance with a battery of 19 standardized tests, showed that total flavonol intake was associated with slower decline in global cognition ( β = 0.004, 95% CI: 0.001, 0.006), episodic memory ( β = 0.004, 95% CI: 0.002, 0.006), semantic memory ( β = 0.003, 95% CI: 0.001, 0.007), perceptual speed ( β = 0.003, 95% CI: 0.001, 0.004), and working memory ( β = 0.003, 95% CI: 0.001, 0.005). Among individuals compounds, kaempferol and quercetin were associated with slower global cognitive decline ( β = 0.01, 95% CI: 0.006, 0.02 and β = 0.004, 95% CI: 0.0005, 0.007), respectively.…”

The Impact of Purple-Flesh Potato (Solanum tuberosum L.) cv. “Shadow Queen” on Minor Health Complaints in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study

“…The longitudinal cross-sectional and co-twin analyses showed that higher anthocyanin intake was associated with improvements in age-related cognitive scores over a 10-year period. Specifically, higher anthocyanin intake was significantly associated with improved executive function and faster and simpler reaction times [26]. Electroencephalography (EEG) data of the acute administration of anthocyanin-rich blackcurrant juice (500 mg of polyphenols) revealed an anxiolytic effect, as indexed by the suppression of the α spectral power and an increase in the slow wave δ and θ spectral powers [27].…”

Dietary flavonoids: a novel strategy for the amelioration of cognitive impairment through intestinal microbiota

“…Although there are few reports regarding the use of flavonoids to address cognitive decline through intestinal microbiota, the efficacy of flavonoids in regulating intestinal microbiota and inhibiting inflammation shows that they have strong potential to prevention of cognitive decline and other neurodegenerative diseases. 82 Wang et al explored the role of intestinal flora metabolites in the oligomerization of amyloid protein in AD by oral administration of grape seed extract (GSPE)mainly catechin, epicatechin and their derivatives, proanthocyanidinsto male Sprague-Dawley rats. It was found that GSPE treatment increased the 3-hydroxybenzoic acid and 3-(3 0 -hydroxyphenyl) propionic acid content significantly in rat brain, and both of them could effectively interfere with the assembly of amyloid peptides into neurotoxin aggregates, suggesting that GSPE had a potential role in preventing the occurrence and development of dementia.…”

“…Although there are few reports regarding the use of flavonoids to address cognitive decline through intestinal microbiota, the efficacy of flavonoids in regulating intestinal microbiota and inhibiting inflammation shows that they have strong potential to prevention of cognitive decline and other neurodegenerative diseases 82 . Wang et al .…”