China health under pressure from rapid change in diets
Increasing wealth and urbanisation on the mainland have led to a dramatic change in eating habits – and a matching shift in the causes of premature death, writes Jeanette Wang
China’s rapid economic growth and emergence as a global power has been accompanied by other speedy developments, two of which made headlines on the same day a fortnight ago: McDonald’s expansion plans, and a new study on the mainland’s shifting disease patterns from infectious to chronic illnesses.
It’s a timely coincidence. Diet is the leading risk factor for premature death on the mainland, accounting for one in three deaths in 2010, according to the study published in The Lancet.
Comparing data from the World Health Organisation’s Global Burden of Disease (GBD) studies of 1990 and 2010, researchers found a rapid change in the nation’s health profile. Infectious, maternal, neonatal and nutritional disorders declined sharply in prevalence as non-communicable diseases rose.
About 85 per cent of China’s 8.3 million deaths in 2010 were due to non-communicable diseases, with stroke, ischaemic heart disease, cancers and chronic obstructive pulmonary disease the top causes of premature death.
“The burden of diseases attributable to individual behaviours and practices is steadily rising,” writes Dr Yang Gonghuan, professor at Peking Union Medical College and co-lead author of the paper. These include diet, smoking, drinking alcohol and physical inactivity.
The research team – from the Chinese Centre for Disease Control and Prevention, Peking Union Medical College and the Seattle-based Institute for Health Metrics and Evaluation – say the key dietary problems are the high consumption of sodium and inadequate intake of fruit, whole grains, nuts and seeds.
On the same day the study was released, McDonald’s announced plans to boost its number of outlets on the mainland from 1,700 to more than 2,000 by next year. It entered the Chinese market in 1990, three years after KFC opened the mainland’s first fast food restaurant in Beijing. KFC now has more than 4,200 outlets in 850 cities.
In the five years to 2012, revenue for the fast food restaurant industry on the mainland grew at about 17 per cent annually to US$89.6 billion, according to research company IBISWorld.
“Ten to 20 years ago in China, not many people could afford to eat at McDonald’s and KFC. But today, they’re everywhere and always overflowing with customers,” says Ma Yu-quan with Zhuhai People’s Hospital.
Increasing affluence and urbanisation have led to a dramatic change in Chinese eating habits, not only to a preference for fast food, but also from a semi-vegetarian diet to one dominated by meat, milk and eggs. This change is matched by a rapid increase in the overweight population, especially in urban areas.
It’s contributing to a growing hypertensive population in China, Ma says. A diet high in salt, fat and sugar, as well as physical inactivity and alcohol and tobacco consumption are all risk factors for high blood pressure.
In his recent study published in the journal PLOS One, Ma reviewed 27 studies on hypertension in China that were published between January 2002 and June 2012. He found that the prevalence of hypertension among Chinese above 15 years of age increased from 5.1 per cent in 1958 to 17.6 per cent in 2002.
Another new study, the China Health and Retirement Longitudinal Study of more than 17,000 Chinese aged 45 and above, showed that more than one in two elderly people, or potentially about 100 million people aged 60 and above, have high blood pressure.
It’s no surprise, then, that hypertension is the second leading risk factor identified in the China GBD study. It accounted for 12 per cent of total years of life lost (due to ill health, disability or early death) and 24.6 per cent of deaths.
High blood pressure is the most common risk factor for cardiovascular disease, contributing to nearly 9.4 million deaths worldwide due to heart disease and stroke every year according to the WHO.
Tobacco is the third major risk. The fraction of deaths attributable to tobacco increased from 12.8 per cent in 1990 to 16.4 per cent in 2010, and the researchers say this will increase because of the lag between consumption and death rates.
Smoking prevalence in China is rising, mainly among men. Fifty-three per cent of Chinese men smoke (one of the highest rates in the world) and 2.4 per cent of women (one of the lowest).
The double whammy of poor diet and tobacco is also having dire consequences on China’s cancer burden. The GBD study found the mainland has five cancers in the top 15 causes of premature mortality: lung, liver, stomach, oesophageal and colorectal. Of these, the burden of lung, liver and colorectal cancers increased between 1990 and 2010.
“Tobacco and diet account for important shares of stomach, colorectal and lung cancers,” say the researchers. “Aggressive tobacco control and national efforts to encourage changes in diet will be important.”
China’s health care system also needs to do some catching up, Yang says. “The health care system lags behind the change in disease patterns.”
Public health programmes to reduce tobacco consumption, sodium intake and other dietary risks are clearly important strategies to tackle cardiovascular diseases, the researchers say.
Because of China’s hospital-centred health system, primary care also needs to be strengthened to be a platform for delivery of interventions such as screening, early detection and disease management.
Education is also important. Awareness of hypertension, for example, has remained low for the past 20 to 30 years, at about 30 per cent of the total hypertensive population, according to Dr Wang Jiguang, a professor of medicine and director of the Shanghai Institute of Hypertension. The China Health and Retirement Longitudinal Study found that 40 per cent of respondents had undiagnosed hypertension prior to the survey.
Demographic shifts spurred by the one-child policy and a rapidly ageing population, and increasing urbanisation, will only intensify the health risks and challenges to China’s health care system. Rising incomes mean the burden attributable to lifestyle factors is likely to increase.
In response to these changing dynamics, the Chinese government launched the China White Paper on Healthcare in December last year, outlining a plan for tackling non-communicable diseases by integrating prevention, early diagnosis and appropriate treatment, along with improved monitoring, surveillance and electronic record-keeping.
The researchers say the government needs to take responsibility for expansion of prevention strategies. “Even small reductions in these risks could generate substantial health benefits,” Yang writes.