The rapid development of the new “Internet Plus” economic form and the increase in broadband penetration has promoted the continuous expansion of electronic transactions across the world [1,2,3]. Online services are gaining popularity due to the convenience of electronic transactions, the wide range of suppliers, and the expansion of delivery services [4, 5]. As a new form of food consumption that is rapidly developing worldwide, online food delivery (OFD) provides consumers with online food ordering and delivery services, thereby changing traditional food production and retail practices. While solving the problem of time cost for individuals and families in food acquisition and preparation, OFD has also gradually changed consumer dietary consumption patterns. In particular, OFD has become more popular in the midst of the COVID-19 pandemic [6,7,8,9]. For example, although the size of the restaurant industry in China did not change significantly from 2019 to 2021, the size of OFD increased by 61.62% in the same time frame. In addition, the penetration rate of OFD increased from 3.87% in 2015 to 19.92% in 2021 . In 2021, there were 544 million OFD users in China , and more than 40% of restaurants in China provide both online and in-person food services .
The global OFD market will reach USD 339.3 billion by 2022, and it is further estimated that the global OFD market will see its average annual growth rate remain at 8.28% from 2022 to 2026 . The rise of OFD has greatly changed the food environment,Footnote 1 triggering changes in the practices of food production, transportation, and consumption worldwide. Consumers are increasingly buying food through online platforms, which has partially replaced traditional home cooking or dine-in patterns.Footnote 2
However, OFD may have negative effects. For example, by saving time spent on food shopping and home cooking, OFD may also reduce physical activity time, resulting in an increase in health problems associated with sedentary lifestyle [8, 13, 14]. Moreover, due to lack of information or labeling, it is difficult to guarantee the nutritional quality of OFD food [15,16,17], not to mention meeting the individualized nutritional needs [18, 19]. These may lead to a negative impact on public health. The increasing prevalence of chronic diseases in younger age groups due to dietary and nutritional health problems has become a widespread social problem in countries including China [20,21,22,23]. Therefore, it is of essential importance to investigate the nutritional value of OFD food and its impact on public health, especially on the risk of chronic diseases. However, only very few reports exist on this topic to date. It is of particular relevance to study this topic in China given the rapid development and huge market size of its OFD market.
According to Statista , the global OFD market will reach USD 339.3 billion by 2022, while China alone will account for USD 158.1 billion, equivalent to 46.60% of the global market. In other words, China has the largest OFD market, the greatest young consumer groups, and also the largest group of undergraduates and graduate students in the world. It is the uniqueness that other countries may not have. Moreover, due to the uncertainty of the COVID-19 pandemic, and more importantly, the convenience and relatively low prices of food ordered online, it is foreseeable that the online food delivery industry will develop faster in China in the future. In this sense, it is unique, forward-looking and representative to study the nutritional quality of OFD foods in China. In general, in addition to the special OFD foods for special groups, the OFD foods in western developed countries are also standardized produced and processed as in China. Objectively, the nutrition of OFD foods is difficult to effectively meet the health needs of the most consumer groups. Therefore, this study is representative to some extent, and the research conclusions have certain reference value for other countries. Nevertheless, the conclusions of this study are merited of greater reference value to China due to the differences in dietary structure and culture among countries in the world.
In the context of OFD’s rapid development and high penetration rate in China, this study aims to evaluate the nutritional quality of popular OFD foods. We analyze the best-selling OFD set meals of the 345 most popular OFD restaurants delivering to addresses near 115 different universities across China. Moreover, a survey was conducted among undergraduates, graduate students, and other young groups aged 18–30 to investigate consumers’ perception of the low nutritional quality of OFD food and analyze its health impact.
In the last few decades, rapid economic development and the need for convenience have led to a rapid global rise of food away from home (FAFH),Footnote 3 including dining out, takeaways, OFD, and other ways of preparing or consuming food outside of home . This has raised concerns regarding the relationship between FAFH quality and public health. Lachat et al. (2012)  and Wallard-Cole et al. (2021)  concluded that FAFH led to increased intakes of energy, total fat, saturated fat, and sodium, as well as decreased micronutrient intake among consumers, and argued that the nutritional quality of FAFH generally did not meet the daily nutritional needs of consumers.
OFD is one of the most important ways through which FAFH has developed rapidly worldwide. Both the size of OFD users and the scope of influence OFD has on the food landscape have attracted the attention of scholars. Young people are the main users of OFD globally . In the US, Canada, and France, consumers aged 18–34 make up more than one-third of all OFD consumers . In Australia and New Zealand, more than 25% of OFD consumers are young people aged 15–34 . Examining a Malaysian context, Eu and Sameeha (2021)  reported that OFD consumers were mainly college students aged 19–29. In China, more than 50% of OFD consumers are young people aged 18–30 . Moreover, a survey on OFD conducted in China showed that 90.48% of the students had used OFD services and 92% of the restaurants around the university had joined online platforms designed to facilitate OFD .
Meanwhile, the impact of OFD on health has attracted great interest from scholars. The overall conclusion is that food through OFD cannot meet individuals’ nutritional needs. For example, Horta et al. (2021)  investigated online platforms where OFD is hosted and found that most restaurants provided a large number of pre-made foods and beverages without sufficient customization to fit individual needs. Partridge et al. (2020)  and Brar and Minaker (2021)  also found that most OFD foods popular with consumers were from takeout franchises with standardized production, which did not include much nutritional customization. Likewise, Stephens et al. (2020)  suggested that standardized online ordering of fast food similar to pizza was popular among OFD consumers in the US. Horta et al. (2022)  found that traditional meals and pasta set mealsFootnote 4 were the food items most frequently pushed to consumers by Brazilian OFD platforms.
In order to further verify the performance that the nutrition of OFD foods is difficult to effectively meet people’s health needs, scholars have conducted a series of studies on this. For example, the “Ghost kitchensFootnote 5” style production and processing mode , resulting in the increasing and serious public health problems . Zang et al. (2018)  found that the low nutritional quality of FAFH was manifested in increased intake of energy, fat, and carbohydrates by consumers. Goffe (2020)  pointed out that the convenient meals available via OFD ordering platforms popular with the global public were generally characterized by high energy and low nutritional quality. Based on data from three countries, Poelman et al. (2020)  suggested that the majority of foods through OFD were unhealthy, and that consumers living in communities with lower socioeconomic levels only had access to a smaller proportion of healthy food types. Partridge et al. (2020)  used data from two international cities to evaluate the characteristics and nutritional quality of foods on OFD platforms, concluding that the most popular foods on the platforms were unhealthy. Brar and Minaker (2021)  also reported that foods available on OFD platforms in Canada were of low nutritional quality and did not meet the requirements of healthy dietary guidelines. After assessing the nutritional quality and marketing attributes of food on Australian OFD platforms, Wang et al. (2021)  speculated that OFD platforms promote unhealthy food, and strongly suggested scholars to further conduct specific research on the nutrition of OFD foods. Similarly, Keeble et al. (2020)  emphasized the necessity to investigate how OFD affects dietary patterns and public health in their research.
Moreover, some studies have investigated specific health problems caused by changes in the food environment as a result of OFD. For example, FAFH, which is closely supported by OFD, has been shown to be generally high in calories, added sugar, saturated fat, salt, and low in nutritional value [26, 35,36,37,38]. These food characteristics have been proven as key risk factors for chronic diseases such as obesity, high cholesterol, diabetes, and hypertension [20,21,22,23]. Nago et al. (2014)  and Wellard-Cole et al. (2018)  also reported a positive correlation between the degree of weight gain and the frequency of FAFH consumption. McCrory et al. (2019)  believed that the rising obesity rate is inextricably linked to the popularity of FAFH. Moreover, Janssen et al. (2018)  and Dana et al. (2021)  suggested that the low-nutrient food through OFD is a key factor leading to overweight and obesity. Stephens et al. (2020)  and Horta et al. (2022)  pointed out that long-term reliance on OFD may lead to chronic diseases such as obesity, hypertension, and diabetes.
Numerous studies have discussed the public health issues caused by food through OFD. However, Stephens et al. (2020) , Partridge et al. (2020) , and Keeble et al. (2020)  pointed out that despite the rapid increase in public dependence on OFD, few objectives and generally accepted research exist demonstrating the health impact of food through OFD from either individual or public health perspectives. Research on the nutritional quality of meals that focuses on consumers in the context of Chinese OFD platforms is even more scarce despite the fact that China has the largest OFD market in the world.
This paper attempts to fill the gaps in the above literature. Considering that the main users of OFD in China are young people , the best-selling OFD set meals from 345 most popular OFD restaurants delivering to consumers on or near 115 different university campuses in China were used as our sample. Different from previous studies, the efforts and contributions of this paper are as follows: Based on the background of rapid development, large scale, large number of users and high penetration rate of OFD in China, we evaluate the nutritional quality of OFD foods based on the dietary guidelines published by the Chinese Nutrition Society, which is believed to be the first study in this field. Moreover, an online survey was conducted among undergraduates, graduate students, and other young groups aged 18–30 to investigate consumers’ perception of the nutritional quality of OFD food and summarize its health impact, which is first to use China as a case.