Dementia is a debilitating condition that affects a person’s ability to remember, think and make decisions, making it difficult for them to carry out daily activities. It has become one of the leading causes of death and disability among the elderly worldwide. In China, which has both the largest elderly population and one of the fastest aging populations, dementia poses significant economic, health and social challenges.
Since dementia is irreversible and effective treatments are limited, early prevention and detection of cognitive decline is critical. Studies have shown that certain lifestyle factors such as physical activity, diet and sleep can affect cognitive function. However, the impact of dietary sodium and potassium on cognitive function remains poorly understood.
In a prospective study published in the journal KeAi Global transitions, a group of researchers from China looked at the impact of dietary sodium, potassium, ratio of sodium to potassium and salt on the cognitive function of a group of elderly people in China. There were 4,213 participants and they were at least 50 years old at baseline. The results are based on cognitive tests and self-reports by the participants.
The research team found that a high sodium intake (>5593.2 mg/day) and a high sodium-to-potassium ratio (>3.8/day) increased the risk of memory impairment in the elderly. Conversely, higher levels of potassium intake (>1653.3 mg/day) were associated with a higher cognitive score; the mean cognitive test score (13.44 at baseline, total score was 27.00) increased by ~1 point when 1000 mg/day of sodium was replaced by an equal intake of potassium.
In addition, the researchers built on previous studies by showing that the effects of dietary sodium, sodium to potassium ratio and potassium on cognitive function have the potential to be mediated by cardiovascular and cerebrovascular disease (CCVD), while the link between salt and cognitive function may be mediated by sleep.
Although China has been trying to limit salt and sodium in people’s diets for more than a decade, its population’s intake remains alarmingly high, exceeding many other countries and the World Health Organization’s recommendation of a maximum of 1,400 mg of sodium per day for people aged 50 and over. -79 years. years and 5 g/day of salt. This high salt intake is often accompanied by insufficient consumption of potassium (1499.0 mg/day in this study vs. the Chinese recommended amount of 3600 mg/day).
The results of the study also confirm previous findings that the dietary sodium-to-potassium ratio could provide a better measure of how these elements affect cognitive function than looking at individual sodium or potassium levels.
Corresponding author, Ai Zhao adds, “Based on our findings, it is reasonable to suggest that reducing sodium intake and appropriately increasing potassium intake is beneficial for cognitive function. Given our results and the nutritional status of the Chinese, it will be important for future studies to focus on determining the optimal ratio of dietary sodium and potassium in the elderly.In addition, the development of strategies to improve the sodium-to-potassium ratio in Chinese diets would provide an should be a priority.”
Reference: “Association of Sodium, Potassium, Sodium/Potassium, and Salt with Objective and Subjective Cognitive Function in the Elderly in China: A Prospective Cohort Study” By Xiaona Na, Menglu Xi, Yiguo Zhou, Jiaqi Yang, Jian Zhang, Yuandi Xi, Yucheng Yang , Haibing Yang and Ai Zhao, Nov 3, 2022, Global transitions.
The study was funded by the Sanming Project of Medicine.