'Fatty' burgers slathered with rich sauces and toppings clog arteries and may also boost the risk of asthma and wheezing, especially in kids, according to a study released Thursday.
Conversely, a so-called Mediterranean diet -- heavy on fruit, veggies and fish, while light on fat -- can help stave off asthma-related respiratory problems, said the study, published in the British Medical Journal.
Asthma is the most common chronic disease in children. Often triggered by dust and allergies, it inflames the airways that brings air in and out of the lungs.
Symptoms include wheezing, chest pains and constricted breathing. Worldwide, the disease afflicts some 300 million people and kills about 250,000 each year, according to the World Health Organisation (WHO).
For reasons that remain poorly understood, asthma has been on the increase over the last 25 years, especially in rich nations.
To assess the extend to which diet may be a factor, researchers led by Gabriele Nagel at Ulm University in Germany examined health data on 50,000 children, aged eight to 12, collected between 1995 and 2005 from 20 rich and poor countries around the world.
Parents were asked to describe what their children ate, and whether they had ever been diagnosed with asthma or severe wheezing.
Nearly 30,000 of the youngsters were tested to see if food and drink influenced their chances of developing allergies.
Diet did not seem to enhance sensitivity to common sneeze-inducing allergens such as grass, pollen and flowering trees.
But it did correlate with the prevalence of asthma and wheezing, according the study.
Children, for example, who ate three or more hamburgers a week along with sugar-filled sodas faced a significantly higher risk.
But tucking into burgers is probably not a direct cause of the disease so much as an indicator of a complex basket of lifestyle factors that favour its development, the researchers noted.
This would explain why comparable burger binging in poorer countries was not associated with the same level of risk.
Consistent with these findings, a Mediterranean diet correlated strongly with a lower incidence of asthma-related symptoms.
Earlier studies have suggested that the antioxidant vitamins found in fruits and vegetables -- especially E, C and B-carotene -- help reduce asthma in adults, while omega 3 polyunsaturated fatty acids in fish are thought to have anti-inflammatory properties.
It was not clear whether the presence of fatty foods or the absence of non-fatty ones was most responsible for the link with asthma.
Meat consumption by itself did not seem to be a factor one way or the other.