Table 3.

List of papers clustered in Topic 2.

Study	Methods	Results	Reference
Zhong et al. (2023)	Dietary intake	Q1 of BC vs. Q4 had lower risks of both CERAD WL decline [odds ratio (OR) = 0.63, 95% confidence interval (CI): 0.44–0.90] and AFT decline (OR = 0.66, 95% CI: 0.47–0.94). Q3 of BC dietary intake had a significantly decreased risk of lower DSST scores (OR = 0.67, 95% CI: 0.48–0.83). For males, dietary BC intake was associated with a decreased risk of AFT decline (OR = 0.51, 95% CI: 0.30–0.85). For females, dietary BC intake was associated with decreased risks of CERAD WL and AFT decline (OR = 0.37, 95% CI: 0.21–0.64; OR = 0.58, 95% CI: 0.37–0.91, respectively)	[29]
Yuan et al. (2020)	Dietary intake	Long-term intakes of total BC and dietary BC were each associated with lower odds of moderate and poor SCF (OR = 0.77 in Q5; p < 0.001)	[31]
Beydoun et al. (2020)	Dietary intake	BC intake was associated with a faster decline and poorer performance on the CDT	[30]
Gerger et al. (2019)	Serum levels	Positive correlation of BC serum concentration with verbal memory assessed through the ISLT (p < 0.01)	[32]
Nooyens et al. (2015)	Dietary intake	No association between BC intake and cognitive decline	[34]
Johnson et al. (2013)	Serum levels	BC serum concentrations positively correlated with most measures of better cognitive function (p < 0.05)	[35]
Péneau et al. (2011)	Dietary intake of BC-rich FVs	The intake of BC-rich FVs was negatively associated with executive functioning scores (p = 0.02)	[38]
Akbaraly et al. (2007)	Serum levels	No associations were found between lower BC serum levels and cognitive impairment	[36]
Perkins et al. (1999)	Serum levels	Decreasing serum levels of BC were not associated with poor memory performance	[43]
Perrig et al. (1997)	Serum levels	BC serum concentration (β0.106, p = 0.035) remained a significant predictor of semantic memory performance	[28]

Q, quartile. Other abbreviations are presented in the Abbreviations section.