A variety of caffeine levels in espresso coffees
I read an interesting article recently about the huge variation in caffeine levels between espresso coffees from the well-known coffee shops found on our high streets. Well, I say interesting, but it was actually very muddled and couldn’t decide if it was actually about caffeine levels in espresso or the potential risk to pregnant women who might be oblivious to the variation.
Assumptions about espresso caffeine levels
There seems to be an assumption (although I’m not sure where this comes from) that a cup of strong coffee contains 50mg of caffeine and that this now appears misleading. There is also a recommendation from the UK Food Standards Agency that pregnant women should restrict their daily caffeine intake to 200mg, which is where the danger apparently lies in this.
Different coffee shops, widely different caffeine levels in espressos
The main thrust of this article was that researchers from Glasgow, Scotland found a sixfold difference in caffeine levels in cups of espresso coffee among 20 coffee shops in the city, including the well known high street chains of coffee shops. They found that Starbucks espressos contained the lowest amounts of caffeine at 51mg per cup, compared with 322mg from an independent coffee shop. Clearly coffee shops belonging to other chains, including Costa, Caffe Nero, Coffee Republic et al, fell between these extremes, with a wide variation in espresso caffeine contents. However, it should be noted that there was also a wide variation in cup sizes among these coffee shops, which could provide consumers with some warning about the caffeine levels within.
Pregnant women should limit caffeine intake
As I mentioned, the focus of the article turned out to be that pregnant women (who shouldn’t be consuming more than 200mg of caffeine per day) might inadverently exceed their recommended daily caffeine limits due to this wide variation in the caffeine content of espressos from the various coffee outlets. Without clear labelling concerning these, “substantial variations in caffeine content”, pregnant women were at significant risk. Apparently these warning arise from an American study in 2008 that found women who consumed more than 200mg of caffeine per day were at 25 per cent greater risk of miscarriage in the first 20 weeks of pregnancy (compared to those who consumed none).
400mg to 500mg of caffeine per day is normally safe and healthy
The article concluded with some general advice about levels of daily caffeine consumption for the rest of the population. A representative of the British Coffee Association said that the overall advice for coffee drinkers is that 400mg to 500mg of caffeine per day is safe and may confer some health benefits, but repeated that it’s important that pregnant women limit their caffeine intake to 200mg per day from all sources.
So, where can you get the most caffeine in your espresso?
Notwithstanding the variety of cup sizes noted in this study it is interesting that espresso coffee produced by seemingly similar processes results in such a wide variation in caffeine content between the serving. While I enjoy Starbucks coffee and particularly like the variety of powdered toppings available, I will be taking the caffeine content into condideration when I next choose where to buy my coffee on a busy high street where there are a number of options to choose from.
