Plant-based eating may protect your brain from the negative impact of exposure to air pollution as you age

A new epidemiological study is the first to explore the interaction between air pollution and plant-based eating on cognitive function in older adults with normal cognition. In their article published last March in The Lancet Regional Health – Western Pacific, authors Zhu et al. looked at the effect of air pollution and diet on the cognitive ability of elderly people in China. They used data from participants in the Chinese Longitudinal Healthy Longevity Survey (CLHLS), available from the National Archive of Computerized Data on Aging (NACDA). The CLHLS is the world’s largest nationally representative survey of centenarians, nonagenarians, and octogenarians, which also includes a comparative group of younger elderly. The CLHLS was meant to determine which of many factors play a role in healthy aging. Seven waves of in-depth surveys between 1998 and 2014 were conducted in 22 provinces in China. An eighth wave of data collection was done in 2018.

Zhu et al. analyzed data from respondents who were between the ages of 65 and 110, from the 2008 wave of the CLHLS. At follow-up, an average of six years later, 1,537 of the 6,525 participants they studied, who had normal cognition at baseline, had developed poor cognitive function. The authors calculated a measure of the respondents’ dietary patterns, and with satellite-derived data that provided annual averages of fine particulate matter, the authors were able to determine respondents’ air pollution exposure. They then evaluated respondents’ cognitive ability using data gathered with the Mini-Mental State Examination (MMSE). They also took into consideration covariates like rural/urban residence, education level, financial status, main occupation before age 60, regular exercise, social and leisure activities, and smoking habits. Zhu et al. found that the effects of long-term air pollution exposure on developing poor cognitive function were lower among the participants who ate more plants. Their findings indicate that promoting plant-based eating would be one strategy to help reduce the effects of air pollution on neurological health, especially for people living in developing countries.

In addition to this one, the ICPSR Bibliography contains hundreds more publications that are linked to CLHLS data.