China's top health authority will intensify monitoring and research into smog to minimize its impact on people's health, amid rising public tension caused by recurrent heavy smog this winter in many parts of northern China.

The National Health and Family Planning Commission will also guide medical institutions in diagnosis and treatment during heavily polluted weather, and improve public health education so members of the public are better equipped with knowledge to protect themselves, commission spokesman Mao Qun'an said at a news conference on Saturday.

At the same time, the commission will increase investment in scientific research on the health impact of heavy air pollution, and promote the formulation of standards for health protection products, such as masks and air purifiers, he said.

The commission began conducting nationwide monitoring of the health impacts of air pollution and risk evaluation in 2013. The project has covered 60 cities in all 31 provinces, municipalities and autonomous regions in China, Mao said.

Based on the monitoring, the density of air pollutants in major cities in North China so far this year has decreased compared with the same period in 2013, and the number of patients in hospitals under monitoring during days of heavy smog has not seen any dramatic increase, he said.

What exact impact the recurring smog will cause to human health in the long term is not clear, Mao said, as large-scale surveys currently underway have not concluded.

Shi Xiaoming, chief of environmental research at the Chinese Center for Disease Control and Prevention, said the nationwide survey by the health commission has been conducted for only a few years and lacks enough data for conclusions about the health impact of smog on humans.

However, initial analysis shows that the rise in density of PM2.5 - particles smaller than 2.5 microns in diameter that pose the greatest health risk - corresponds to rising death rates and rising incidence of certain diseases, such as respiratory and cardiovascular disease, he said. There is no firm evidence that smog alone induces lung cancer, he added.

Wang Yu, director of the disease control center, advised people to take precautionary measures to reduce harm from smog, such as using air purifiers indoors and wearing protective masks when going outdoors.

"People should take positive measures to address the negative psychological impact of smoggy weather, as a negative mindset over a period of time can lead to depression," he said.