A stressful childhood lined with destabilizing experiences - such as having divorced parents, being exposed to crime, or moving house frequently - leads to habits that could predict adult obesity, a new study finds.
The CDC also estimate that the yearly healthcare expenses of individuals living with obesity are more than $1,400 higher than those of people with a normal weight.
Previous research has convincingly linked adult obesity with low socioeconomic status both in childhood and later in life.
Now, a recent study from Florida State University in Tallahassee, in collaboration with the Kellogg School of Management at Northwestern University in Evanston, IL, goes beyond that.
Dr. Jon K. Maner, from the Department of Psychology at Florida State University, and his colleagues have looked at how other destabilizing events from a person's childhood - such as exposure to divorce, crime, and other types of social and environmental instability - could lead to a lifestyle that promotes obesity.
Their findings were recently published in Proceedings of the National Academy of Sciences.
Stable versus unstable childhoods
The researchers used "Life History Theory" (LHT), an analytical framework that, in a behavioral science context, places the amount of stability experienced in a person's childhood at the root of their lifestyle and life choices, or "life-history strategies."
LHT signals two kinds of life-history strategies: faster life-history strategies and slower life-history strategies. Faster life-history strategies are marked by the search for immediate gratification, such as having more sexual partners in early life, having more children earlier, and exhibiting a generally impulsive behavior.
According to LHT, people with faster life-history strategies are likely to have had unstable childhoods, in which they were exposed to privations of one kind or another. This is why, later in life, they are prone to favor "living in the moment," without adequately planning for the future.
"Experiencing an unpredictable environment in childhood sensitizes people to the idea that it's difficult to plan for the future because if you don't know what's around the next corner, you live for the now. They end up focusing on short-term rather than long-term goals and they're not good at delaying gratification."
Dr. Jon K. Maner
At the opposite side of the spectrum, people with slower life-history strategies are likely to have had very stable and well-structured childhoods, which led them to expect a stable future.
Slower life-history strategies are focused on long-term outcome behaviors characterized by more cautious deliberation.
Slow life-history strategy more healthful
Despite previous research pointing to links between childhood stress and adult obesity, this is the first time that LHT has been used to explain behaviors that lead to an unhealthful diet.
Dr. Maner and his colleagues looked at how lack of stability in childhood can be a predictor of behaviors that lead to obesity in adulthood.
The study found a direct link between fast life-history strategies and eating habits that can lead to obesity. The researchers observed that people with more instinct-driven life choices were much likelier to eat even when they were not hungry.
"If you don't know where the next meal is coming from, it would make sense to eat what you can now. But people with a slow-life-history strategy [...] are inclined to listen to their body and eat based on their current needs," says Dr. Maner.
This is why the study is important, in the researchers' view: it allows people to identify the root of their bad dietary practices, and it may educate parents on how best to adapt their behavior to ensure their children's well-being later in life.
"Our research suggests it's not just about reducing stress, it's more about creating structure and predictability for children," explains Dr. Maner.
"Routines teach children to have expectations that, when met, result in a sense of certainty and structure. Theoretically, that feeling of predictability instills a slower-life-history strategy, which may reduce obesity in adulthood."
Dr. Jon K. Maner