Chinese have serious concerns over the safety of food, environment and personal information, according a report released on Monday.

Food safety is the biggest concern for Chinese, with 11.8 percent of people believing food is "very unsafe", 15.1 percent feeling it is "unsafe" and 28.1 percent saying it is "not very safe", according to the 2016 Annual Report on Social Mentality of China by the Chinese Academy of Social Sciences.

The statistics are based on a survey of 15,870 people across the country in August and September.

Those surveyed appeared to be, in general, neither happy nor unhappy. Addressing the statement "I am a happy person", respondents were asked to select a score on a spectrum between one (totally disagree) and seven (totally agree). The average score of the respondents was 4.18.

Addressing the statement of "society is just" using the same spectrum, the average score was 3.78.

The report found that economic pressure is the biggest source of stress, followed by marriage and family relations.

Respondents in first-tier cities, which refers to Beijing, Shanghai, Guangzhou, Shenzhen and Tianjin, suffer from more pressure than those living in smaller cities, the report said.

However, pressure caused by family and social relations is higher in smaller cities, because of limited job opportunities and a less fair social environment, it said.

Among various professions, people tend to trust teachers the most, followed by doctors, policemen, judges, lawyers, migrant workers, taxi drivers, bosses, experts, baby sitters, journalists, businessmen, government officials, government clerks, clergymen and brokers, the report said.

People born in the 1990s tend to trust others the most, while those born in the 1950s find it most difficult to trust others. Those in rural regions trust people more than those in urban areas, while those living in the city who don't hold a hukou - permanent residence permit - are the most vigilant among all groups, the report said.

It also found that Chinese netizens care most about topics associated with livelihood and celebrity news. They are also highly engaged in discussing government policy and issues surrounding national sovereignty, it said.