A drink made from broccoli sprouts can protect humans from toxic air pollution in China, research has shown.
An experiment conducted in eastern China's Jiangsu province found that feeding villagers beverages concocted from broccoli sprouts had various salutary effects, including helping the body flush out air pollutants.
Researchers from Johns Hopkins Bloomberg School of Public Health, as well as the University of Minnesota's Masonic Cancer Center, held a trial involving nearly 300 Chinese men and women living in one of the country's most polluted regions.
The results reveal that the daily consumption of half a cup of the broccoli sprout beverage causes faster, and longer, bodily excretion of benzene, a known human carcinogen, and acrolein, a lung irritant.
The broccoli drink also provided a source of sulforaphane, a plant compound shown through animal studies to help prevent cancer.
"Air pollution is a complex and pervasive public health problem," said John Groopman, one of the study's co-authors.
"To address this problem comprehensively, in addition to the engineering solutions to reduce regional pollution emissions, we need to translate our basic science into strategies to protect individuals from these exposures.
"This study supports the development of food-based strategies as part of this overall prevention effort."
The 12-week trial included 291 participants who live in a rural farming community in Jiangsu Province, China, approximately 50 miles north of Shanghai. For the study, 229 women and 62 men aged between 21 and 65 were involved.
Participants in the control group drank a beverage made of sterilised water, pineapple and lime juice, while the beverage for the treatment group also contained a dissolved freeze-dried powder made from broccoli sprouts containing glucoraphanin and sulforaphane. Urine and blood samples were taken during the trial.
The results showed that among the participants receiving the broccoli sprout beverage, the rate of excretion of the carcinogen benzene increased 61% on the first day and continued to rise throughout the 12 weeks.
In addition, the rate of excretion of the irritant acrolein increased 23% during the trial.
"This study points to a frugal, simple and safe means that can be taken by individuals to possibly reduce some of the long-term health risks associated with air pollution," said Thomas Kensler, a co-author.
"The ultimate answer [to China's pollution] lies in Beijing with the policymakers," Kensler told the Wall Street Journal.
Air pollution causes as many as 7 million deaths a year worldwide, according to the World Health Organization, and has in recent years reached perilous levels in many parts of China.
The study was published in journal Cancer Prevention Research.