Sleep disturbances have become a pressing public health problem. The association between diet and sleep health has attracted increasing attention in recent years. This study aimed to elucidate the associations of dietary carbohydrate amount and carbohydrate quality with sleep quality. This study was conducted among 4772 participants with a mean age of (62.4 ± 6.3) years in the Lifestyle and Healthy Aging of Chinese Square Dancer Study. Dietary data were collected using a 64-item food frequency questionnaire. Carbohydrate quality was assessed by the carbohydrate quality index (CQI), which is based on four components: dietary fiber intake, glycemic index, whole grain/total grain ratio, and solid carbohydrate/total carbohydrate ratio. Sleep quality was evaluated by the Pittsburgh sleep quality index. Multivariable logistic regression analysis was performed to analyze the association of carbohydrate amount and quality with sleep quality. After controlling for sociodemographic, lifestyle, and multiple disease-related factors, the odds ratio for the highest vs. the lowest quintile of the CQI was 0.64 (95% confidence interval (CI) 0.53, 0.78; P-trend < 0.0001). In contrast, no significant associations were observed between carbohydrate amount and sleep quality. The findings suggest that higher dietary carbohydrate quality, rather than carbohydrate amount, was associated with better sleep quality. This study provided a diet-related sleep-improving strategy for the general population.

Specific carotenoid (e.g., β-carotene, lutein, lycopene) has potential benefits for cognitive health demonstrated in both human and animal studies. To mimic the composition of carotenoids in the human diet and to avoid the overdose of any specific carotenoid, we developed a mixture of 6 carotenoids (7.5 mg/(kg·day), including 9.0% α-carotene, 35.8% β-carotene, 12.2% lutein, 1.6% zeaxanthin, 41.0% lycopene and 0.4% β-cryptoxanthin) and investigated its long-term neuroprotective effect and potential mechanism in APP/PS1 mice, a well-established animal model for Alzheimer’s disease. Initiated at 3 months with a total of 4 months’ gavage intervention, the dietary carotenoids mixture was found to alleviate cognitive impairment and amyloid β deposition in the brain (P < 0.05). Consistently, dietary carotenoids mixture restored Nissl bodies and the density of dendritic spines, and increased protein expression of Synapsin and PSD95 in the hippocampus and cortex of APP/PS1 mice (P < 0.05). In addition, carotenoids were also found to reduce oxidative stress and inflammation level and increase autophagy (P < 0.05). Importantly, carotenoids have been shown to up-regulate the expression of silent information regulator 1 (SIRT1) and brain-derived neurotrophic factor (BDNF) in the brain (P < 0.05). Together, long-term intake of dietary carotenoids mixture could alleviate the cognitive deficit in APP/PS1 mice, wherein the SIRT1/BDNF pathway might play an important role. Our findings could contribute to the development of effective dietary and nutritional intervention strategies for delaying neurodegeneration in the aging population.