In China, each province has its specific socio-economic level, food habits, health infrastructures and communication facilities. Thus, the nutritional status of the population shows significant inter province variations since it results from a varying combination of factors.
For children under five years of age, the prevalence of underweight ranged from 3% in Beijing to 39% in the province of Hainan while that of stunting ranged from 7% in Beijing to 56% in of Guizhou. The highest prevalence of stunting were observed in the same provinces as those of underweight. According to the WHO classification, the children in the provinces of Fujian, Jianxi, Hunan, Guangxi, Hainan, Sichuan, Guizhou, Yunnan, Qinghai and Xinjiang were found to be highly affected by stunting (>40%) and those in Guanxi and Hainan also showed a prevalence of underweight >30%.
The marked improvement in nutritional status is shown by a reduction of the prevalence of underweight from 22%, in 1987 to 12% in the 1992. In China, the under-five mortality rate (U5MR), an important indicator of the socio-economic development and health and nutritional status of a society was found to be 47‰ in 1996. However, a large number of infectious diseases, such as respiratory, intestinal infections and hepatitis remain the main cause of death in children under five, with malnutrition being an aggravating factor.
The provinces of Guangxi and Hainan were found to be affected by adult chronic energy deficiency with more than one fourth of them with a BMI under 18.5 kg/m2 . Patterns of child and adult malnutrition in part overlap in that both show extremely poor nutritional status in the provinces of Guangxi and Hainan.
In adults, average BMI values were similar for both males and females (22.0 kg/m2). About 10% of the adult population had a BMI below 18.5 kg/m2 while a significant proportion were overweight or obese (15%). In Shangai, Tianjin and especially in Beijing overweight and correlated diseases are becoming a public health problem. In fact, in Beijing almost half of the adult population is overweight. In the last decade, a clear shift to the right is seen in the distribution of BMI values, suggesting an improvement in adults' nutritional status over this period.
In the past decade, there has been an improvement in the nutritional status of the Chinese population. This improvement results from socio-economic factors, increased availability of potable water, better distribution of food throughout the country, lower morbidity and improvement of health facilities.
The national average intake of energy slightly decreased from 2485 to 2328 kcal/caput/day between 1982 and 1992 and this is probably due to the more sedentary lifestyle of the population. The findings from the 28 provinces surveyed in 1992 showed that the average daily per capita energy intake varied from 1913 kcal in Hainan to 2720 kcal in Anhui. Between 1982 and 1992, there was a reduction in the intake of all major food groups except for meat, fish, milk and milk products, eggs and oils and fats. As a consequence, there has been an increase in the share of protein and fat in total energy intake from 10.8% to 11.8% for protein and from 18.4% to 22.0% for fat.
There are important inter provincial variations in the share of protein and fat in total energy intake. The share of protein ranged from 9.8% in Sichuan to 13.1% in Shangai and that of fat from 14.0% in Gansu to 31.5% in Beijing. In all the provinces surveyed, cereals mainly rice and wheat flour represented the main source of energy providing from 54% to 78% of total energy intake respectively in Beijing and Gansu. The diet in China is mainly based on vegetable products which provide 81% and 63% of total protein and fat intake respectively.
The Chinese diet is particularly deficient in iodine but China has started with the Universal Iodization Salt campaign to control IDD and this programme is promising to achieve its goals by the year 2000. It is also deficient in iron and women above 18 years of age are the most affected group with 23% suffering from anaemia. There are important inter provincial variations in the prevalence of anaemia in adult women which ranged from 2% to 52% respectively in Nei Mongol Zizhiqu and Shanghai.