Between 1966 and 1976, around 16.5 million urban teenagers relocated from Chinese cities to rural villages as part of a nationwide programme during the Cultural Revolution. Known as "sent-down youth", or zhiqing, these workers typically spent five to six years in the countryside before returning to cities. The connections formed between these workers and the villages that hosted them endured for decades, creating social and information networks between specific rural communities and specific cities.

This historical episode is the basis for new research into one of the least examined groups in the migration debate: the parents and grandparents who stay in the village while working-age family members leave for the city. The research paper, Rural-Urban Migration and the Health of Left-Behind Older Adults, published in Health Economics, was authored by Dr Tess Stafford, a Senior Lecturer in the School of Economics at UNSW Business School, Dr Xiaoyun Zhang in the School of Economics at Zhejiang Gongshang University; and Associate Professor Katja Hanewald in the School of Risk & Actuarial Studies at UNSW Business School.

The research explores two forces reshaping China: labour mobility and population ageing. By 2024, China had almost 300 million migrant workers – an increase of 2.2 million from the previous year. At the same time, 13.7% of the population was aged 65 or older, a share projected to more than double to 30.2% by 2050. Rural pension and health coverage have expanded, but families in the countryside still rely heavily on relatives for support. When those relatives leave, the question of who fills the gap extends from being a social to an economic one.

"China's rural-to-urban migration is widely regarded as the largest internal migration in history and has transformed both the country's labour market and family structures,” said A/Prof. Hanewald.

The methodology problem behind migration research

Working out whether migration causes poorer health among those left behind is difficult because migration decisions and parental health are intertwined. Families with sicker parents might send a child away to earn money for treatment, or a child might stay specifically to provide care. Villages with poor infrastructure might push younger residents to leave while independently damaging the health of everyone who remains. Simply comparing migration rates with health outcomes risks capturing all of these forces at once, in either direction.

Learn more: Digital resilience: how a rural Chinese community adopted digital social innovation

The sent-down youth program supplies a way around this problem. The researchers combine historical records of which villages received sent-down youth, and from which cities, with present-day wage growth in those sending cities. Villages with longstanding social ties to fast-growing cities should see more present-day migration, for reasons unrelated to the current health of those who remain. Using data from the China Health and Retirement Longitudinal Study (CHARLS), a nationally representative survey of people aged 45 and over, the researchers find that this approach strongly predicts village-level migration rates, with statistical strength well above the threshold economists use to trust an instrument.

What the numbers show

The results challenge the assumption that labour mobility lifts everyone connected to it. A one standard deviation increase in a village’s migration rate (roughly a 19 percentage point rise) is associated with a 0.36 standard deviation drop in the ability to manage basic daily tasks such as dressing and eating; a 0.17 standard deviation drop in managing more complex tasks such as cooking and medication; a 0.40 standard deviation decline in lung function; and a 0.21 standard deviation decline in mental health. In some specifications, self-reported life satisfaction falls too, by 0.09 standard deviations. The pattern is similar (regardless of age and gender) though older people are hit harder on physical measures, while younger left-behind adults show more emotional and cognitive strain.

"China's rural-to-urban migration is widely regarded as the largest internal migration in history and has transformed both the country's labour market and family structures"

KATJA HANEWALD

As the authors put it: “To the extent there are gains from rural-urban migration, our results strongly suggest that older individuals are not the beneficiaries of these gains.”

Why the money doesn’t compensate

Household expenditure on utilities, medical services and communication falls when migration rises, according to the research. However, remittances from non-resident children decline rather than rise – so the wealth gains one might expect from migration fail to materialise.

Physical assistance needs increase across all age and gender groups, with most met by spouses, while younger people and men report a gap between the help they need and the help they receive. Contact with children, in person and remotely, drops. Older individuals and men take on more farm work to compensate for lost labour, work that can itself erode health when strenuous.

A/Prof. Hanewald explained: “Relaxing hukou restrictions to allow migrants to bring their aging parents with them could help mitigate the negative effects of migration documented in our study.”

What this means for practitioners

For anyone working in policy, aged care, insurance, or regional economic development, the lesson is that labour mobility programs built around productivity gains for migrants and receiving cities can impose a measurable health cost on older people who do not move.

The paper points to levers already in motion in China: expanding rural health insurance coverage, building out home- and community-based aged care, expanding pension and cash transfer schemes, and reforming the hukou household registration system so migrants can bring their ageing parents with them rather than leave them behind. China’s New Cooperative Medical Scheme, which covered 88% of the rural population (more than 800 million people) by 2010, offers one model; the Home- and Community-Based Elderly Care Services pilot launched in 2016 is another.

Subscribe to BusinessThink for the latest research, analysis and insights from UNSW Business School

For businesses operating in markets undergoing similar transitions, from India to parts of Southeast Asia, the mechanism applies generally: when labour shifts geographically, the people left holding the household together absorb costs that don’t appear in productivity statistics.

“The key takeaways to think about are policies that protect older individuals from the loss of support from migration: expand access to health insurance; expand access to health care; expand pension and cash transfer programs; relax the household registration (hukou) system,” Dr Tafford concluded.