London, December 03: Mothers-to-be please note: Pregnant women who drink coffee at popular cafes may unwittingly be putting their unborn baby’s health at risk, researchers have warned.
An analysis of espressos from 20 coffee shops in the UK by researchers from Glasgow University found big variations in the amount of caffeine in each cup they offer.
Worryingly, the strongest example contained more than 50 per cent more caffeine in a single cup than a pregnant woman is advised to take over the course of an entire day, the Daily Mail reported.
As too much caffeine can result in miscarriage or a low birth weight, pregnant women are advised to limit themselves to 200mg of caffeine a day — which is equivalent of four cups of strong coffee containing 50mg of caffeine each.
But only one of the 20 coffees studied by the researchers found to have contained around this amount. All of the others were stronger.
Four had more than 200mg in a single cup, with the strongest having more than 300mg, the researchers said.
“The levels of caffeine per serving varied more than six-fold. At the low level, a pregnant woman might safely drink four cups per day without significantly exceeding the recommended intake,” said Dr Alan Crozier, who led the study.
“At the higher end of the scale, even one cup of espresso will be well in excess of the advised limit. There is clearly a problem.
People at risk could unwittingly ingest far more caffeine than they would ever dream of,” he said.
The researchers, who detailed their findings in the Royal Society of Chemistry journal Food and Function, said caffeine crosses the placenta to the unborn baby and usually takes five hours to break down in the body to half its previous level.
But the process can take up to 30 hours in some groups, including children, liver disease sufferers and pregnant women, they said.
An unborn baby’s liver will struggle to break down caffeine, with potential long-term consequences. Even taking the Pill can hamper processing of caffeine, said Dr Crozier.
For their study, the researchers bought single-shot espressos from 20 coffee shops in Glasgow and measured their caffeine content.
The Starbucks espresso was found to be the weakest, with 51mg of caffeine, while espresso from Costa Coffee had more than three times as much caffeine, with a reading of 157mg.
At the top of the table was the espresso from Patisserie Francoise, with 322mg of caffeine.
Repeating the experiment several times did not change the figures, said Dr Crozier, adding, “There is every possibility this applies to all coffee shop coffees and not just espresso and not just in Glasgow.”
According to the researchers, the type of bean, roasting process, grinding conditions and the coffee-making technique can all affect caffeine content, as well as the actual amount of coffee used.
Meanwhile, a spokesman for Starbucks said: “It is nothing new that caffeine is bad for pregnant women.”
–PTI–