Adequate dietary nutrition is crucial for health, reducing the risk of various diseases. The World Health Organization emphasizes nutrition's role in disease prevention. Poor diet contributes significantly to non-communicable diseases, a leading cause of death globally. Education plays a vital role in improving dietary intake, encompassing both general education level and nutrition education specifically. Studies in developed countries show a strong link between higher education and better diet quality, with education often being a more influential factor than income. Education influences health perceptions, lifestyle choices, and food variety. In China, despite significant improvements in rural residents' dietary quality since its economic opening, disparities remain between urban and rural areas. Rural residents exhibit poorer dietary quality, higher malnutrition rates, and increased susceptibility to both under- and over-nutrition. The "Healthy China 2030" initiative highlights improving rural dietary health as crucial for national well-being. This study addresses the challenge of improving rural dietary health by focusing on the upward spillover effect of education, hypothesizing that children's higher education positively impacts their parents' dietary intake. This is particularly relevant in China due to significant intergenerational educational differences. The study addresses endogeneity concerns using an instrumental variable approach, leveraging the implementation of China's Compulsory Education Law. The study uses the 2011 CHNS data, focusing on middle-aged and elderly parents in rural China, differing from many studies that focus on younger parents.

Extensive research, primarily in developed countries, demonstrates a strong positive relationship between educational attainment and dietary nutrient intake and quality. Higher education correlates with better health outcomes and healthier lifestyle choices, including balanced diets. Studies show that higher education is associated with greater food variety, increased consumption of fruits and vegetables, and reduced consumption of less healthy options. In the US, education is strongly linked to both income and diet quality. Similar findings are seen in Australia and Europe. Research in China also indicates a positive association between higher education (especially among women) and better dietary patterns and nutrient intake. While prior research shows a downward spillover effect of education (parents' education impacting children's diet), this study explores the upward spillover effect, focusing on how children's higher education may influence their parents' dietary habits. This is important given the potential for knowledge transfer within families and the unique context of rapid educational development in China.

This study utilizes data from the 2011 China Health and Nutrition Survey (CHNS), focusing on middle-aged and elderly (45 years and older) parents in rural families. The sample includes various provinces representative of China's diverse geographical and socioeconomic conditions, ensuring some extent of national representation. CHNS data is well-suited for studying intergenerational relationships, offering comprehensive information on household members, including educational levels, income, and health conditions. The 24-hour dietary recall method is employed to capture detailed food consumption data. Food consumption is categorized into nine types based on the China Food Composition Table 2004, and nutrient intake is calculated based on this table, focusing on calories, carbohydrates, proteins, and fats. Dietary quality is measured using the Dietary Balance Index (DBI-2007), considering both insufficient and excessive intake. The DBI-2007 includes High Bound Score (HBS), Low Bound Score (LBS), and Diet Quality Distance (DQD), reflecting excessive, inadequate, and imbalanced intake, respectively. To address the potential endogeneity issue (unobserved variables affecting both children's education and parents' diet), a two-stage least squares (2SLS) instrumental variable (IV) approach is used. The implementation of the Compulsory Education Law (CEL) in different provinces serves as the instrumental variable, as it affects children's education but is not directly related to parents' dietary intake. The impact of the CEL varies across provinces depending on pre-existing educational development levels, a factor incorporated into the model. Control variables include age, gender, marital status, parental education level, family income, BMI, and weekly hours of various types of physical labor. The study conducts separate analyses for food consumption, nutrient intake (both total and from plant/animal sources), and diet quality, examining the impact of children's education on each.

The instrumental variable estimation shows that children's higher education significantly impacts parents' dietary habits. Specifically, higher children's education levels are associated with a significant decrease in parents' consumption of cereals and vegetables, but a significant increase in consumption of livestock meat, poultry, milk, eggs, and aquatic products. The Cragg-Donald Wald F-statistic consistently exceeds 10, confirming the validity of the chosen instrumental variables. Regarding nutrient intake, higher children's education is associated with a significant reduction in parental calorie and carbohydrate intake, but a significant increase in fat and protein intake. Analyzing nutrient sources reveals that higher children's education leads to decreased energy and protein intake from plant-based foods, but increased intake of plant-based fats and all three macronutrients (calories, protein, and fat) from animal sources. This suggests a shift towards a diet richer in animal protein and fats. Regarding diet quality, measured by the DBI-2007, higher children's education results in lower scores for HBS, LBS, and DQD, indicating improvements in dietary balance and reduced imbalances. Heterogeneity analysis reveals stronger effects of sons' education compared to daughters' education on parents' dietary intake, likely due to traditional cultural norms in rural China where sons play a more significant role in parental care. Similarly, mothers show a stronger response to children's education compared to fathers, possibly due to the traditionally higher status of fathers in rural Chinese families. Further analysis demonstrates that higher children's education significantly improves parents' dietary knowledge, increasing their agreement with statements promoting healthy dietary practices.

The findings support the hypothesis that children's education has an upward spillover effect on parents' dietary nutrient intake. This effect is likely mediated through increased dietary knowledge transfer from children to parents, leading to more informed dietary choices and a shift towards a more balanced diet. While previous research has emphasized the downward spillover effect of education, this study highlights the significant contribution of children's education to improving parental health, particularly in the context of rural China where nutritional knowledge gaps may be more prevalent. The observed shift towards higher consumption of animal products might be interpreted as a reflection of improved economic conditions alongside the acquisition of dietary knowledge.

This study provides strong evidence of an upward spillover effect of education on dietary nutrient intake in rural China. Higher children's education significantly improves parents' food consumption, nutrient intake, and diet quality. This highlights the importance of investing in rural education as a strategy for improving population health. Future research could explore the long-term health outcomes associated with these dietary improvements and investigate other potential mechanisms mediating the intergenerational effect of education on health behaviors.

The reliance on self-reported dietary data from the 24-hour recall method may be subject to recall bias and potential inaccuracies in reporting food consumption. The study's focus on rural China may limit the generalizability of the findings to other contexts. Additional research is needed to investigate other potential factors that might contribute to the relationship between children's education and parents' dietary habits and health.