Last week's big coffee health news was that coffee may help prevent endometrial cancer in women. This week, the coffee buzz is about the dangers of highly caffeinated coffee for prengnant women. Researchers from the University of Glasgow got shots of espresso from 20 different shops around the town and analyzed their caffeine content. What they found was a bit of a shock -- the caffeine content in the various shots ranged from a low of 51mg to a high of 322mg. Traditional wisdom says that a strong cup of coffee has about 50mg of caffeine. For espresso, the USDA pegs a one-ounce shot of espresso at 61mg of caffeine.
In the wake of the report, there's been a wave of news articles warning pregnant women away from a daily shot of espresso at the local coffee shop. Most medical associations suggest that pregnant women should keep their caffeine intake below 200mg a day -- four of the samples in the Glasgow study had caffeine levels above 200mg in a single shot. If women are going by the traditional expectation of about 60mg of caffeine per shot and figuring they could safely sip 3 shots of espresso, they could conceivably be downing up to 4 times the recommended amount of caffeine. Caffeine has been linked with a higher risk of low birth weight in babies, and some people have toxic reactions, which include headaches, chest pains, anxiety and abdominal cramping, to too much caffeine. Pregnant women, children and women who take hormonal birth control pills are more likely to display caffeine toxicity because their systems take longer to clear caffeine out.
Of course, no barista or coffee aficianado should have been too surprised that different espressos have varying levels of caffeine -- we all know that some coffees have more of a caffeine jolt than others. The difference between 51mg and 322mg is a pretty huge one, though, especially if you're sensitive to caffeine or watching your caffeine intake because you're pregnant. What do you think? Should pregnant women avoid espresso altogether? Should coffee shops and roasters start testing caffeine levels and label them (which, of course, still only accounts for part of the variance, since there are so many factors in coffee extraction that can affect the levels of caffeine in the finished product)? Or should we start carrying around a packet of caffeine test strips to decide whether you can have one shot of espresso or three?