Population aging is a common challenge faced by most countries. According to the World Health Organization (WHO), the elderly population aged 60 and over is expected to reach 2 billion by 2050, accounting for 22% of the total population (1). Due to the decline in the birth rate and the increase in life expectancy, China became an aging society in 2000 (2). In 2021, China had 200 million people aged over 65 years (14.2% of the whole population) (3), and the number is forecast to double by 2050 (4). In contrast to developed countries such as Japan and the United States, China is experiencing “getting old before getting rich,” resulting in the emergence and accentuation of multiple health problems (5). Numerous studies observed gender differences in health status and most health problems (6). Women live longer but have higher rates of disability and poor health than men. Men have better health but die at a younger age than women. This phenomenon is known as the “male–female health-survival-paradox” (7). It is unclear whether Eastern populations, with different living conditions and cultures from contemporary Western societies, also experience gender differences in health. Therefore, exploring gender differences in health may have important implications for improving the health status and health outcomes of older adults in China.

Mental health is one of the most neglected global health issues, with approximately 15% of adults aged 60 and over suffering from a mental disorder (8). Loneliness is one of the key indicators of poor mental health, and people with existing mental health problems are also more likely to experience loneliness (9). In the context of rapid urbanization, changing family structures and the erosion of kinship ties in China, the prevalence of loneliness is gradually increasing, and 28% of older people have experienced loneliness (10). Gender differences in loneliness are also observed, but the results of existing studies are inconsistent. Some studies showed that men reported more intense feelings of loneliness than women, particularly those without a spouse or partner (11, 12). However, a WHO report noted that older women are vulnerable to loneliness, possibly related to longer lifespans and more severe health problems (8). In fact, for cultural reasons, older people, particularly men in China, may not receive timely treatment for loneliness because they are more reluctant to admit their loneliness. Therefore, investigating loneliness and its gender differences in older adults is of great significance for improving their overall health and quality of life.

Previous research demonstrated that there are associations between loneliness and health-related behavioral risk factors (BRFs) in older adults (13). Smoking, physical inactivity, and unhealthy diet were found to be significantly associated with a higher risk of loneliness (14). Evidence from longitudinal studies found that lonely individuals were less likely to engage in social interactions and physical activities (15), and more likely to smoke (10), drink alcohol (16), and experience sleep problems (17). What’s more, individuals with a co-occurrence of multiple health-related BRFs have been shown to be at higher risk of depression, anxiety, distress, and even chronic diseases and mortality than those with a single health-related risk behavior (18, 19). It’s also worth noting that the health-related BRFs were more likely to cluster in older men living in rural areas with lower socioeconomic status (20). However, there is a paucity of research investigating the association between the co-occurrence of BRFs and loneliness among the Chinese elderly, which means more attention is needed and essential.

The evidence for cultural differences in loneliness is complex, and people from different societies and cultures may experience varying degrees of loneliness (21). One study showed that living in a more collectivistic society was linked to greater loneliness (22). Han, the most populous ethnic group in China, has multiple internal ethnic branches, including the Hakka. There are around 80 million Hakkas worldwide, with 50 million residing in Guangdong, Jiangxi, and Fujian provinces in China. Compared with other Chinese, the Hakka people have distinct traditions and cultures. Previous studies showed that the Hakka people were forced to migrate from northern China to the south away from their homeland for historical reasons, which left them with limited access to resources (23). On the one hand, they gradually formed a living arrangement that a whole village lived together in a large “castled house” (tu lou), where people worked together and socialized closely. On the other hand, poor living conditions forced them to learn medical knowledge about various medicinal herbs and develop unique health-related behaviors to fight disease and maintain health in order to survive natural disasters such as extreme weather, poisons, and animal attacks. In recent years, with the change of lifestyle and the weakening of traditional filial piety, the traditional extended family has been gradually replaced by private nuclear families, and a rising number of the Hakka elderly live alone, which may put them at higher risk of loneliness and lead to some changes in their health-related BRFs. Therefore, this study aimed to explore the gender differences in the relationship between loneliness and health-related BRFs among the Hakka elderly. We hope to draw more attention to loneliness and health-related BRFs among Hakka older adults and to provide a theoretical basis for local governments to develop and implement relevant, effective, and targeted intervention programmes.

The word “Hakka” means “guests,” “foreigners,” or “strangers,” which is related to the history of their multiple migrations, implying that they are not the original inhabitants of the region (23). Therefore, although the Hakka is an ethnic branch of Han Chinese, their lifestyles, beliefs, and culture are in part distinct from those of ordinary Chinese people. This study found that the Hakka elderly who had physical inactivity, insufficient leisure activities participation, unhealthy dietary behavior, smoking, or irregular sleep behaviors had greater loneliness, which is consistent with other studies (30, 31). Surprisingly, although the unhealthy weight was associated with loneliness in both male and female Hakka elderly groups, we found that males with unhealthy weight had significantly lower ULS-8 scores than those with healthy weight, while females with unhealthy weight had significantly higher ULS-8 scores, which caused the relationship between unhealthy weight and loneliness in the total population not statistically significant. Possible explanations for this phenomenon are as follows: Firstly, females are more likely to maintain a healthy weight because of the body size stereotype, and obese people are more likely to face stigma and discrimination. Secondly, due to the traditional Chinese idea that “body fat represents rich” and better living conditions nowadays, some older adults, especially those who survived the “Great Famine” in the 1960s, may mitigate the effects of loneliness by consuming more food (32), and this phenomenon is more evident in males (33). Thirdly, an unhealthy weight may be a sign of poor health status. Previous studies showed that individuals with underweight (34), overweight, or obese (33) are more likely to have mental health issues than those with a healthy weight. Compared to the male elderly, the female elderly had higher rates of disability and poor health (7), which could further cause unhealthy weight and loneliness issues.

Physical activity can help to combat loneliness by improving people’s moods and developing their social networks and social capital (35). Studies showed that loneliness was pervasive among physically inactive persons (36), particularly in middle-aged populations (37). Varied effects of physical activities were also found on males and females (38). Our result showed that a positive association occurred only in the Hakka female elderly, which may be because females are better at building friendships in the process of participating in exercise (38). But in fact, more than half of the Hakka female elderly who participated in our survey lacked physical activity. This may be explained by the low socioeconomic status of Chinese women and the poorer motor function of females than males (7). Compared with ordinary Chinese elderly, Hakka elderly people have a unique living arrangement. They usually live in villages or family units in “tulou” and have closer social networks and bonding social capital, which means that mobilizing Hakka older people to participate in physical activity may have a significant effect on the improvement of loneliness. In the past few years, square dancing has been a particularly popular activity among the Chinese elderly, especially females (39). Therefore, government agencies could encourage the Hakka female elderly to engage in physical activities by expanding sports venues and increasing sports equipment for physical activities like square dancing to reduce their loneliness.

Our findings showed a negative correlation between leisure activity and loneliness among the total Hakka older population. The effectiveness of leisure activities in preventing and alleviating loneliness among the elderly has been proven (40). Participation in leisure activities is important for social interaction and social contact among the elderly in China. For older persons who have retired, leisure activities can provide them some opportunities to meet people and engage in social events, which could meet their psychological needs (41). Our study also found that the negative association between leisure activities and loneliness was significant for older males but not for older females. Insufficient participation in leisure activities could leave males with fewer social interaction opportunities and narrower social networks (42), which may cause negative emotions such as loneliness, depression, etc. In China, the participation rate in leisure activity among the elderly has shown a downward trend over the past two decades (43). The Hakka people have traditionally been dominated by a culture of extended family. Older males, who were often the most authoritative members of the extended family, may suffer more loneliness from the changes of children leaving home and declining social status. Therefore, we should advocate strengthening the monitoring of engagement in leisure activity among the Hakkas, particularly the Hakka male elderly, and call for more research on the negative trends of leisure activities.

Unhealthy diets are currently becoming a major threat to the health of Chinese people. Previous studies showed that the prevalence of unhealthy diet was highest among people aged 65 years and older (44). Our results showed that unhealthy dietary behavior was strongly correlated with loneliness in the total and male population, which was consistent with previous studies (45). With the population migrating and life expectancy increasing, rural hollowing out is becoming more serious, and the number of empty-nest elderly is gradually increasing. One study showed that the empty-nest elderly were more prone to loneliness and depression than the nonempty-nest elderly (28). Older men living alone had significantly worse eating patterns and more unhealthy eating behaviors than those living with a spouse (29). On the one hand, the Hakka elderly may eat their favorite but unhealthy foods to alleviate loneliness. On the other hand, unhealthy diets may lead to a variety of physical and psychological problems and increase the prevalence of chronic diseases, which indirectly leads to a stronger sense of loneliness among the Hakka elderly. Unfortunately, this study did not explore the differences between the specific dietary styles of the Hakka elderly and the general Chinese elderly. Therefore, we should further study the association between the dietary situation and the mental health status of the Hakka elderly, and government departments should focus on the empty-nest elderly living alone when formulating and implementing policies.

It is difficult to come to a firm conclusion about the relationship between drinking and loneliness. Some studies suggested that lonely persons tend to drink excessively (46, 47), while other studies found that loneliness is associated with lower alcohol consumption (48, 49). Our findings observed a negative association between drinking and loneliness in the Hakka elderly. There are some possible explanations: On the one hand, drinking is considered an essential social activity in Chinese culture. A study of retired older adults found that adults who were socially isolated in their retirement communities were less likely to drink regularly and heavily than those who were more socially connected (50). A stronger sense of belonging brought by group drinking was found to be associated with reduced loneliness (48). The Hakka elderly have fewer opportunities to socialize, which decreases their access to alcohol intake but heightens their sense of loneliness. On the other hand, the unique socio-ecological environment of the Hakka area has shaped a winemaking culture, and the Hakkas’ tolerance, openness, and hospitality are reflected in their drinking culture, allowing them to drink more alcohol but helping to feel less lonely. Thus, it is hard to distinguish whether loneliness prompted the Hakkas who initially drank to drink less or whether the drinking habit reduced loneliness in the current cross-sectional study. Moreover, there is considerable evidence that alcohol consumption is detrimental to health (51), and it would be unwise to conclude that high alcohol intake can reduce loneliness based on our findings alone. Therefore, further research is warranted to understand the underlying physiological and psychosocial connection between loneliness and drinking, which may assist in the development of more effective interventions and preventative measures for loneliness.

In China, the prevalence of sleep problems has been reported to range from 8.3 to 49.7% (52). Older people who felt lonely were found to have a higher prevalence of sleep-related issues, such as insomnia and sleep deprivation (17, 31). This may be because sleep is particularly sensitive to psychological stressors (53). Our study found that irregular sleep was positively associated with loneliness in the total, male and female Hakka elderly, and this is in line with previous studies (17, 31, 53, 54). As a matter of fact, the brain of lonely people maintains a certain level of alertness during sleep, which leads to a decrease in sleep quality and an increase in depression (54). What’s worse, sleep problems could further increase people’s loneliness. Patients with loneliness display a foul mood or low mood throughout the day due to poor sleep quality, numerous nighttime awakenings, daytime sleepiness, and exhaustion (55). In summary, all the evidence suggests that improving sleep health is crucial to the prevention and treatment of loneliness, and further empirical studies are needed. Hakka people have unique beliefs and culture. They believe in gods and have special reverence and worship for the sky, land, flora and fauna. Worshiping the gods can help them relieve anxiety, sadness, pain and bring peace of mind. It can be considered from this point to improve the sleep problems and loneliness of the Hakka elderly.

We also found that the number of BRFs was strongly positively associated with loneliness among the Hakka elderly after adjusting for confounding factors. Besides, there are some differences in the number of BRFs among the Hakka elderly by gender, and most of them had at least one health-related risk behavior. One study showed that about 57.0% of Chinese people had at least two BRFs, and the prevalence was higher among older men, those living in rural areas, and those with lower socioeconomic status (24). Another evidence suggested that those with lower socioeconomic or educational levels were four to five times more likely to have multiple BRFs (56). However, existing behavioral interventions remain focused on preventing and controlling of single health-related risk behavior, ignoring the potential linkages between multiple BRFs. Previous studies indicated implementing interventions that address multiple risk factors simultaneously is more effective than interventions that target a single risk factor (57). Therefore, comprehensive interventions to address multiple BRFs should be quickly planned and implemented to reduce health-related risk behaviors and improve the loneliness of the Hakka elderly.

In conclusion, the present study has gained an overall understanding of the relationship between health-related risk behaviors and loneliness among the Hakka elderly in Fujian. Our study showed that the Hakka elderly with BRFs were more likely to feel lonely than those without BRFs, except for drinking and unhealthy weight. After adjusting for social-demographic variables, we found that factors such as insufficient leisure activities participation, unhealthy dietary behavior, and irregular sleep were positively associated with loneliness among the Hakka male elderly. In the Hakka female elderly, physical inactivity and irregular sleep were positively associated with loneliness, while drinking was negatively related to loneliness. Furthermore, the association between the number of BRFs and loneliness was strongly positively correlated, and individuals with more BRFs were more likely to self-report loneliness. Hence, we recommend that when formulating health policies and intervention measures, government departments should not only pay attention to specific single health-related BRFs according to gender, but also explore the co-occurrence of multiple BRFs, and adopt comprehensive strategies to reduce the loneliness of the elderly.

To the best of our knowledge, this study is the first research targeting the Hakka elderly to reveal the relationship between their BRFs and loneliness. The following limitations of the present study should be noted: Firstly, only correlation rather than causal relationship was explored due to the cross-sectional design of our study, so further prospective research is needed. Secondly, our study only investigated the Hakka elderly in Fujian, China. However, the Hakka people are also distributed in Guangdong, Jiangxi in China, and other Southeast Asian countries like Thailand, Malaysia, and Singapore. Our samples cannot well summarize the entire Hakka elderly population. Therefore, the conclusions of this study need to be extrapolated to other populations with caution, and it is necessary to conduct further comparative studies between the Hakka elderly and the ordinary Chinese elderly in the future. Thirdly, non-response bias was not assessed, as only those who agreed to participate were included in the analyses. Lastly, there are differences in the patterns of behavior co-occurrence, and this study did not explore the impact of such differences on loneliness. It is necessary for future studies to use methods such as clustering or latent class analysis to identify behavior patterns and explore their relationship with loneliness.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

XL conceived this research. HC and WR were responsible for the methodology. HC and WR conducted software analyses, gathered resources, curated all data, wrote and prepared the original draft. XL was responsible for project administration. YC and LC conducted necessary validations. XL conducted a formal analysis and managed the investigation. XL reviewed and edited the manuscript, was responsible for visualization, supervised the project, and acquired the funding. All authors contributed to the article and approved the submitted version.

The present study was mainly supported by the National Natural Science Foundation of China (Grant No. 72204047). Meanwhile, this work was also partially supported by the Natural Science Foundation of Fujian Province, China (Grant No. 2022 J01234).

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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