While millions of US households face food insecurity (17.9 million in 2011) as defined by the US Department of Agriculture, new studies by the department indicate very few households remain food insecure for extended periods of time.

The findings were published June 3 in an article, “Food insecurity in US households rarely persists over many years,” by Mark Nord, a sociologist in the Food Assistance branch of the USDA In the summary, Nord says between 2008 and 2011, the percentage of households experiencing food insecurity held within a narrow range of 14.5% to 14.9%.

He says, “But, were these mostly the same households year after year? Or, was food insecurity usually a transient condition?”

The Economic Research Service of the USDA commissioned two studies, looking into patterns of food insecurity. As part of the research, households were interviewed periodically over periods of five years or more between 1998 and 2002. A second study looked at food security in households with children between 1998 and 2007.

“Both studies found spells of food insecurity to be generally of short duration,” Nord says. “For example, in the (first) study, 16.9% of households were food insecure in at least one of the survey years. Of those, about half (8.5% of households in the study) experienced the condition in only a single year, and only 1% percent of households in the study were food insecure in all five years of the study. The proportions were similar in the second study). In both, very low food security, the severe range of food insecurity marked by reductions in food intake below levels considered appropriate, was even more likely to be transient.”

While the short-lived nature of food insecurity may be interpreted as “good news,” Nord says the other side of this coin is that a much larger number of households face food insecurity at some time over a period of several years.

For the USDA, Nord says the findings mean a “double challenge” must be met — having the flexibility to quickly address the needs of those facing food insecurity on a short-term basis while also meeting “the long-term needs of the smaller proportion of households whose food insecurity results from chronic or persistent conditions.”