During the eight-day Chinese New Year holiday, traditionally filled with marathon meals, Liu Han, a 24-year-old Beijing resident, managed to avoid the pitfall of food waste plaguing many festive gatherings.

Dining out with friends four times throughout the holiday, Liu meticulously planned each meal to prevent food waste. He consulted restaurant review apps for group-buying deals, gauged portion sizes by observing nearby tables, and confirmed with staff to prevent over-ordering.

"People tend to have big eyes but a small stomach," Liu said, using a phrase describing someone who appears to have a big appetite, but in reality, cannot consume as much.

This approach marked a significant shift from past years, where "saving face" often led to excessive ordering.

While previously hesitant to speak up for fear of appearing to be penny pinching, Liu has joined a growing movement of waste-conscious diners advocating for more detailed menus to combat the "asymmetric information" that contributes to food waste.

"Public attitudes toward food waste have significantly changed," Liu said, highlighting how more informative menus could eliminate the need for app consultations or staff inquiries.

This cultural shift is partly driven by years of government campaigns promoting clean plates.

The China Association of Business Professionals, a civil society group, recently drafted guidelines encouraging food providers to revamp menus to offer more than just dish names, prices and pictures.

The guidelines suggest including ingredient quantities and recommended serving sizes. Additionally, allergen warnings and descriptions of textures and flavors are recommended.

"Research shows that beyond 'face culture', a key cause of waste is the information gap between providers and consumers," said Wang Ling'en, a researcher who drafted the guidelines. "The size of dishes and the taste are major factors."

According to a 2018 survey by the Chinese Academy of Sciences and the World Wide Fund for Nature, gatherings and banquets contribute significantly to food waste, with nearly 38 percent of food wasted at larger events. This exceeds the average 11.3 percent waste in China's urban catering sector.