The literature on the health effects of recessions is surprisingly contradictory: while some research on the individual-level effects of joblessness and money trouble indicates "that people are healthier when incomes are higher," other studies have found that economic expansions are associated with higher mortality across groups and for all causes of death (excluding suicide).

But a look at Google queries during the Great Recession suggests that our recent economic contraction at least made people feel worse physically, as reflected by their online behavior.

For the study, which was published in the February issue of The American Journal of Preventive Medicine, researchers examined search information downloaded from Google's public database (google.com/trends). Defining the Great Recession as having lasted from December 2008 through 2011, they found that this period "was associated with increases in a range of health concerns, potentially indicative of worsening population health."

Among the issues on people's minds: "arrhythmia, back pain, cancer, congestion, chest pain, gastric pain, headaches, hernia, joint pain, pregnancy, toothache, and ulcer concerns." Headache queries rose the most, with 41% excess relative volume, followed by hernia (37%), chest pain (35%), and arrhythmia (32%) queries.

"A common topic across themes was pain," the researchers report. A rise in pain complaints, potentially tied to the crisis, was reported by The Wall Street Journal as far back as March 2009.

The researchers call their approach "a new methodological lens for one of the most studied phenomen[a] in public health", pointing out that "[m]ost studies rely on self-reported survey responses." So although people usually complain of "generally poorer health" or worse physical functioning during a recession, the Google trends data provides insight into specific concerns—whether or not people disclose them on surveys or seek treatment for them at clinics.

The insalubrious influence of the recession seems to have persisted: the study's lead author, San Diego State University professor John W. Ayers, told The New York Times, "By the end of the great recession in 2011, queries were still substantially higher than before the recession. People were not getting better with the economy. People were still potentially much sicker."

"Potentially" being an important word, as many who've worriedly googled a symptom should know.