03 August 2021
2 minutes of reading
Increasing flavonoid consumption reduced the risk of subjective cognitive decline among men and women, according to findings published in the United States. neurology.
“Although some small, short-term intervention trials provide some evidence supporting the beneficial role of flavonoids in cognitive decline, epidemiological studies have been inconclusive. Furthermore, it is unclear whether different flavonoid subclasses and specific foods that contribute to flavonoid intake have different associations with cognitive function.” Tian-Shin Yeh, MD, PhDA research fellow in epidemiology at the Harvard T.H. Chan School of Public Health and colleagues wrote. “We therefore investigated associations between flavonoid intake and subsequent subjective cognitive decline (SCD) using extensive repeated dietary assessments from over 20 years of follow-up in two large prospective male and female cohorts.”
Yeh and colleagues analyzed data from 27,842 men aged 40 to 75 from the Health Professionals Follow-up Study (HPFS; 1986-2002) and 49,493 women aged 30 to 55 years from the Nurses’ Health Study (NHS; 1984-2006).
The researchers used Poisson’s regression to evaluate associations between dietary flavonoids and subsequent SCD, including flavonols, flavones, flavanones, flavan-3-ols, anthocyanins, polymeric flavonoids and proanthocyanidins. The NHS cohort took seven repeated food frequency questionnaires (SFFQ) to determine long-term average dietary intake and their SCDs were evaluated in 2012 and 2014. The HPFS cohort received five replicate SFFQs and their SCD was evaluated in 2008 and 2012.
The pooled results showed that higher flavonoid consumption was associated with a lower probability of SCD, after adjusting for age, total energy intake, major non-dietary factors, and specific dietary factors. When comparing the highest and lowest quintiles of flavonoid consumption, the pooled multivariate-adjusted ORs of 3-unit increases in SCD were 0.81 (95% CI, 0.76-0.89).
In addition, the strongest correlations in the pooled results were seen for flavones (OR = 0.62; 95% CI, 0.57-0.68), flavanones (OR = 0.64; 95% CI, 0.58-0.68) and anthocyanins (OR = 0.76; 95%). CI, 0.72-0.84).
Limitations of this study include the lack of basic cognitive assessments, as well as the potential presence of recall bias in the participants, and generalizability as the participants were mostly white healthcare professionals.
Yeh and colleagues conclude, “Our findings support the benefit of higher flavonoid intake for maintaining cognitive function in US men and women.” “These findings may suggest future interventional studies in the investigation of possible therapeutic or preventive strategies for cognitive decline, including the possible effects of certain flavonoids on cognitive function and effective dosage. Meanwhile, consumption of flavonoid-rich foods such as strawberries, citrus fruits, and fruit juices can reduce cognitive may be useful for maintaining function.