Smoking hookahs are more harmful than traditional cigarettes, say scientists who found that puffing a water pipe for just half an hour can lead to the development of cardiovascular risk factors.

The study by researchers at the University of California, Los Angeles (UCLA) in the US is a direct contradiction of marketing efforts claiming that hookah smoking is less hazardous to health than cigarettes.

Researchers measured heart rate, blood pressure, arterial stiffness, blood nicotine and exhaled carbon monoxide levels in 48 healthy, young hookah smokers before and after 30 minutes of hookah smoking.

The study showed that a single session of hookah smoking increased heart rate (by 16 beats per minute) and blood pressure; and significantly increased measures of arterial stiffness, a key risk factor in the development of cardiovascular conditions such as heart attack or stroke.

The increase in arterial stiffness was comparable to data seen from cigarette smokers after smoking a cigarette. "Our findings challenge the concept that fruit-flavoured hookah tobacco smoking is a healthier tobacco alternative. It is not," said Mary Rezk-Hanna, an assistant professor at the UCLA.

Studies have shown that as cigarette use continues to decline, hookah smoking is rising, especially among youth and particularly among college students.

"We know that flavoured tobacco products are frequently the first kind of tobacco product used by youth," Rezk-Hanna said.

"One of the major issues with hookah is the fact that the tobacco is flavoured with fruit, candy and alcohol flavours, making hookah the most popular flavoured tobacco product among this audience," she said.

Results of the study are particularly concerning because it measured what appears to be the lower limit of hookah use (half an hour), researchers said.

Typically, a hookah session can last for several hours, potentially increasing the levels of nicotine and other toxins being absorbed into the body.

Stiffening of arteries and the aorta are important signs of progression of hypertension, which raises the risk of heart attacks, stroke and other cardiovascular disorders.

Previous studies have shown that cigarettes, smokeless tobacco, cigars and most recently e-cigarettes produce similar rates of arterial stiffening seen in this hookah use study.

However, hookah smoking remains more popular, due to marketing efforts as well as social trends. In previous studies, when participants were asked why hookah smoking was more attractive than cigarette smoking, 48 per cent of them replied that it was because of the fruity flavours and smells.