Sugar-sweetened beverages consumption is associated with worse cognitive functions in older adults: from the national health and nutrition examination survey and food patterns equivalents database

Burden of cardiometabolic disease attributable to sugar sweetened beverages consumption in North Africa and the Middle East from 1990 to 2021

Objectives

The consumption of sugar-sweetened beverages (SSBs) is recognized as a significant risk factor for chronic non-communicable diseases (NCDs). Accurate estimates of the burden of SSBs are crucial for preventing, controlling, and treating associated diseases to achieve the Third United Nations Sustainable Development Goal of reducing premature mortality from NCDs by one-third by 2030. In this study, we aim to systematically assess the regional patterns and trends in the burden of SSBs in the North Africa and the Middle East (NAME) region. By analyzing regional differences, the study identifies specific areas where SSBs consumption has a more significant impact on public health.

Methods

The study data were retrieved from the Global Burden of Disease (GBD) study 2021. This study analyzed the impact of SSBs on mortality, years lived with disability, years of life lost, and disability-adjusted life years (DALYs) in 21 countries in the NAME region from 1990 to 2021. Our analysis considered various factors, including sex, age, region, and socio-demographic index.

Results

In 2021, DALYs attributable to SSBs there were 315,312 (95% uncertainty interval, 140,854 to 503,347) in absolute terms reflecting 518.3% (424.9 to 642.2) increase over three decades. From 1990 to 2021, the age-standardized rate of DALYs attributable to SSBs increased by 118.5%, from 27.9 (11.4 to 43.9) to 61.0 (27.6 to 97.0) per 100,000 population. Qatar (246.7 [113.1 to 404.5]), Saudi Arabia (201.2 [87.1 to 314.2]), and Bahrain (180.1 [78.4 to 295.8]) had the highest age-standardized rate of DALYs. The highest attributable DALYs and mortality from SSBs consumption were due to diabetes mellitus in all countries in 1990 and 2021. In 2021, Qatar (224.7 [104.9 to 365.5]), Bahrain (167.0 [74.8 to 274.8]), and Saudi Arabia (153.1 [75.3 to 230.4]) had the three highest age-standardized rates of DALYs from diabetes mellitus attributed to SSBs.

Conclusions

NAME witnessed a substantial increase in the burden attributable to SSBs. Alarmingly, exposure to SSBs has principally contributed to the increased burden of diabetes mellitus and chronic kidney disease. Among the region's countries, exposure and attributable burden trends vary considerably. It is imperative that governments and health authorities within the NAME region work together to combat SSBs' detrimental effects. Local, socioeconomic, and educational factors need to be considered when developing prevention and treatment strategies at the individual, community, and national levels.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-025-01578-9.

The association between dietary dark green vegetable intake and cognitive function in US older adults

Dark green vegetables include dark green leafy vegetables and broccoli. They are sources of many essential nutrients, including vitamins A, B and C, folate, fibre, carotenoids and flavonoids. This study aimed to explore the association between dietary dark green vegetable intake and cognitive function in US older adults. We included 2344 older adults (≥60 years old) from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 cycles. Dark green vegetable consumption was assessed using a continuous variable (cups/day) and two categorical variables. The first categorical variable classified participants into non-consumers and consumers based on whether they consumed dark green vegetables. The second categorical variable grouped participants into four levels of dark green vegetable consumption (non-consumers, consumers with low intakes, consumers with moderate intakes and consumers with high intakes). We used five continuous variables with non-normal distribution to assess cognitive function, including a composite z-score and the standardised scores of four individual cognitive tests. The four cognitive tests included the Immediate Recall Test (IRT), the Delayed Recall Test (DRT), the Animal Mobility Test (AFT) and the Digit Symbol Substitution Test (DSST). The standardised scores of the four cognitive tests were calculated using the mean and standard deviation of each cognitive test score. The composite z-score was calculated by averaging the standardised scores of four cognitive tests to evaluate global cognition. We used multiple linear regression models to examine the association between dietary dark green vegetable intake and cognitive function. Our findings indicated that dark green vegetable intake was positively associated with global cognition (β [95% CI]: 0.17 [0.04, 0.30]; p = 0.016) and IRT (β [95% CI]: 0.26 [0.08, 0.43]; p = 0.009) and DRT (β [95% CI]: 0.21 [0.05, 0.36]; p = 0.012) standardised scores. Individuals with high intake of dark green vegetables showed notably better global cognition (β [95% CI]: 0.16 [0.05, 0.28]; p = 0.010) and showed higher IRT (β [95% CI]: 0.22 [0.07, 0.38]; p = 0.010) and DRT standardised scores (β [95% CI]: 0.21 [0.07, 0.36]; p = 0.007) compared with the non-consumers. Blood neutrophil counts mediated the cognitive benefits of dark green vegetables (Proportion: 9.5%, p = 0.006). In conclusion, our findings suggest that dark green vegetable consumption may have favourable effects on cognitive function in US older adults, especially on immediate and delayed learning abilities. The underlying mechanisms include the ability of dark green vegetables to reduce blood neutrophil levels, an indicator of decreased systemic inflammation. Increasing dietary intake of dark green vegetables may be a beneficial intervention to improve cognitive health in the older US population.

Association between plant-based dietary patterns and cognitive function in middle-aged and older residents of China

BACKGROUND

Plant-based diets may protect against cognitive impairment; however, observational data have not been consistent.

OBJECTIVE

This study aimed to evaluate the association between plant-based dietary patterns and cognitive function.

METHODS

The study recruited 937 participants who were asked to complete food frequency questionnaires to assess the quality of their plant-based diets using the overall plant-based diet index (PDI), the healthful PDI (hPDI), and the unhealthful PDI (uPDI). Cognitive function evaluated using the Montreal Cognitive Assessment (MoCA) test. Logistic regression was used to explore the association between plant-based dietary patterns and the prevalence of mild cognitive impairment (MCI), while multiple linear regression was used to analyze the association between plant-based dietary patterns and cognitive scores.

RESULTS

The prevalence of MCI was 26% among the 937 participants. There was a significant association between higher uPDI scores and higher odds of MCI, with Quintile 4 compared with Quintile 1 showing an odds ratio of 2.21 (95% confidence interval 1.35, 3.60). Higher uPDI scores were associated with a lower total MoCA score and poorer performance in various cognitive domains. There were no significant associations between the PDI, the hPDI, and cognitive function. Consuming whole grains, nuts, and eggs once a week or more were associated with a lower risk of MCI, whereas frequently consumption of pickled vegetables was associated with an increased risk of MCI.

CONCLUSIONS

Unhealthy plant-based diets were associated with cognitive impairment, while whole grains, nuts, and eggs may protect cognitive function; pickled vegetables are associated with cognitive impairment.

Fruit and Vegetable Intake and Risk of Disabling Dementia: Japan Public Health Center Disabling Dementia Study

BACKGROUND

Fruits and vegetables contain abundant amounts of antioxidant vitamins such as vitamin C, α-carotene, and β-carotene. Few prospective observational studies have investigated the effects of fruit and vegetable intake on the risk of dementia, and the results are inconsistent.

OBJECTIVES

Our aim was to examine associations between fruit and vegetable intake and the risk of disabling dementia.

METHODS

We conducted a follow-up survey within the Japan Public Health Center-based Prospective Study involving 42,643 individuals aged 50-79 y at baseline (2000-2003). Dietary fruit and vegetable intakes and related antioxidant vitamin intakes (i.e., α-carotene, β-carotene, and vitamin C) were determined using a food frequency questionnaire. The diagnosis of disabling dementia was made based on the daily living disability status related to dementia under the Japanese long-term care insurance program from 2006 to 2016. Hazard ratios and 95% confidence intervals for disabling dementia were estimated using area-stratified Cox proportional hazard models adjusted for potential confounding factors.

RESULTS

A total of 4994 cases of disabling dementia were recorded. We observed an inverse association between total fruit and vegetable intake and the risk of dementia among males and females: the multivariate hazard ratios (95% confidence intervals) for the highest compared with lowest quartiles of intake were 0.87 (0.76, 0.99) (P- trend = 0.05) among males and 0.85 (0.76, 0.94) (P- trend = 0.006) among females. Among antioxidant vitamins, vitamin C intake was inversely associated with the risk of dementia among males and females: the multivariate hazard ratios (95% confidence intervals) for the highest compared with lowest quartiles of intake were 0.71 (0.61, 0.84) (P- trend < 0.0001) among males, and 0.76 (0.67, 0.86) (P- trend < 0.0001) among females.

CONCLUSIONS

Fruit and vegetable intake and dietary intake of vitamin C may contribute to reducing the risk of disabling dementia among males and females.

The Impact of Free and Added Sugars on Cognitive Function: A Systematic Review and Meta-Analysis

A relationship between excessive sugar consumption and cognitive function has been described in animal models, but the specific effects of sugars in humans remains unclear. This systematic review and meta-analysis aimed to evaluate the current knowledge, research characteristics, and quality of evidence of studies investigating the impacts of free and added sugars on human cognition in healthy participants. The review identified 77 studies (65 experimental trials, n = 3831; 9 cross-sectional studies, n = 11,456; and 3 cohort studies, n = 2059). All cohort studies and eight of the nine cross-sectional studies found significant positive correlations between added sugar consumption and risk of cognitive impairment. Four studies identified reduced risk of cognitive impairment associated with natural fructose-containing foods. The majority of randomised control trials assessed short-term glucose facilitation effects on cognitive outcomes. The results from these studies suggest the need for a tightly regulated blood glucose level, dependent on individualised physiological factors, for optimal cognitive function. A meta-analysis of a subset of studies that assessed the impact of glucose on recall found improvements in immediate free recall compared to controls (p = 0.002). The findings highlight the potentially detrimental effect of excessive, long-term, or prenatal added sugar consumption on cognitive function. Further research is needed to examine the specific effects of free and added sugars on cognitive function.