BACKGROUND

As the global population ages, there is an increasing prevalence of mild cognitive impairment and dementia. Protecting and preserving cognitive function in older adults has become a critical public health concern.

METHODS

This study utilized data from four phases of the Chinese Longitudinal Healthy Longevity Survey conducted from 2008 to 2018, encompassing a total of 2454 participants. Latent growth curve modeling was employed to analyze the trajectory and role of protein intake frequency and cognitive function.

RESULTS

The frequency of protein intake among older adults tends to rise, with individuals exhibiting higher initial levels experiencing smaller subsequent increases. Conversely, cognitive function generally declines, with those starting at higher levels experiencing more pronounced decreases. Notably, the initial frequency of protein intake is positively correlated with the initial level of cognitive function ( = 0.227, 95% CI: 0.156 to 0.299, < 0.001), but does not significantly influence the rate of change in cognitive function ( = -0.030, 95% CI: -0.068 to 0.009, = 0.128). The rate of change in protein intake frequency is positively associated with the rate of change in cognitive function ( = 0.152, 95% CI: 0.023 to 0.280, = 0.020).

CONCLUSIONS

The alterations in protein intake frequency are linked to alterations in cognitive function among older adults. Maintaining a stable high frequency of protein intake or increasing the frequency of protein intake may contribute to stabilizing cognitive function as well as reducing the risk of cognitive impairment and dementia in older adults.