LONDON: British scientists have found that children who drink plenty of apple juice may be less likely to develop symptoms of asthma, a chronic disease that affects airways.

Apple juice is already known to help protect from many diseases associated with aging, including heart disease and cancer. Aside from obvious fruit vitamins like vitamin C, apple juice also contains the mineral nutrient boron, which is thought to promote healthy bones.

The research done by Britain's National Heart and Lung Institute, published in the European Respiratory Journal, is the latest study to link apples and lung health.

Researchers led by Peter Burney at Aberdeen University looked at five to 10-year-old schoolchildren in the Greenwich area of London, asking their parents about their child's fruit intake and about any symptoms they had suffered.

While the researchers did not find any link between apple juice consumption and a reduced chance of an actual asthma diagnosis, the link between wheezing and drinking the juice was quite strong.

The appearance of wheezing symptoms is one of the most important signs that a child is at increased risk of asthma although many with the symptoms are not eventually diagnosed with the illness.

The apple juice involved did not have to be fresh apple juice. Juices made from concentrate were also effective, the researchers say.

A similar, but weaker, benefit was found for children eating bananas at least once a day compared with less than once a month, according to a website.

"It was possible that phytochemicals in apples, such as flavanoids and phenolic acids, were helping to calm the inflammation in the airways which is a key feature of both wheezing and asthma," Burney said.

He said it was not clear why a link between eating apples and reduced asthma symptoms, already spotted in other research in adults, did not appear among these children.

"Further studies are needed to confirm the protective effects of apple juice from concentrate and bananas," he said.

According to World Health Organization (WHO), Asthma is the most common chronic disorder in childhood. About 300 million people suffer from asthma and 255 000 people died of the disease in 2005.

When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swell. This reduces the amount of air that can pass by, and can lead to wheezing sounds.