Amanda at Pandagon links to and talks about this article in the NY Times about the link between caffeine and miscarriages. The Boston Globe had an article about the same study, but had a decidedly different slant. The Times article only looks at the one study and has the conclusion:
Too much caffeine during pregnancy may increase the risk of miscarriage, a new study says, and it suggests that pregnant women may want to reduce their intake or cut it out entirely.
Many obstetricians already advise women to limit caffeine, although the subject has long been contentious, with conflicting studies, fuzzy data and various recommendations given over the years.
The Globe article looks at the same study but together with another study on caffeine that also came out last month and has this conclusion:
Confusing messages are nothing new when it comes to what you should notdo during pregnancy, so here’s another one: A growing body of evidence suggests that high caffeine consumption – on the order of more than two or three cups of coffee a day – increases the odds of miscarriage, while low to moderate caffeine consumption doesn’t pose a significant risk.
The Globe article to my mind is much better. Seeing the results together, I would come to the same basic conclusion as the Globe article: that it seems large amounts of caffeine can cause problems, while small amounts do not and the confusion is in the middle (the one study says 10 oz of coffee is too much, the other says 16 oz or even a bit more is not a problem). I would think that most women are fine if they drink one or two cups, but this isn’t interesting since the message is again–everything in moderation.
Amanda talks about how this type of reporting happens more often with women. I agree, but I think the bigger problem here is that news reporting doesn’t go well with studies of this sort. A consensus from this type of study only comes from many studies (since the study is observational, it’s difficult to know if other causes are missed, the Times study says it is not associated with any other known risks but of course there are still unknown risks), while news articles will focus on the study that just came out. The Globe article is much better in talking about problems with this type of study:
But Klebanoff points out that the level at which this paper identified miscarriage risk – more than 200 milligrams per day – overlaps with the “moderate” level deemed not risky in the Savitz paper. While he can’t explain the discrepancy, he points out that a challenge in these studies is that people’s bodies process caffeine differently, so a “moderate” amount for one individual might be “high” for another.
Both of the new studies have their drawbacks, Riley said. She points out that it is hard to standardize the amount of caffeine in coffee from different retailers, and that people don’t always accurately report their own behavior in surveys.
Still, she says, the evidence is compelling enough to suggest that pregnant women curb their caffeine intake. But that doesn’t mean they need to go cold turkey.
“Would I cut it out completely? Probably not; the literature doesn’t support the idea that a little bit of caffeine is harmful,” Riley said.
Riley comes to that conclusion because other studies besides these two show problems with high levels of caffeine. I wish all reporters had the same standards. Advantage Globe here.