Body weight is impacted by lifestyle and environment, such as medication use, genetics, timing of food intake, stress, gut bacteria and nighttime light exposure.
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Jennifer Kuk from York University in Toronto, Canada, said, "However, it also indicates there may be other specific changes contributing to the rise in obesity beyond just diet and exercise."
For the study, researchers analyzed dietary data of nearly 36,400 US adults collected by the US National Health and Nutrition Survey between 1971 and 2008. The team also used the available physical activity frequency data of 14,419 adults in the 1988 to 2006 period.
Lead researcher Ruth Brown from York University said, "We observe that for a given amount of self-reported food intake, people will be about 10% heavier in 2008 than in 1971." The investigators also found that for a given amount of physical activity level, people were about 5% heavier in 2006 than in 1988. Brown said, "These secular changes may in part explain why we have seen the dramatic rise in obesity."
Kuk explained, "Our body weight is impacted by our lifestyle and environment, such as medication use, environmental pollutants, genetics, timing of food intake, stress, gut bacteria and even nighttime light exposure. Ultimately, maintaining a healthy body weight is now more challenging than ever."
The findings will be published in the upcoming issue of Obesity Research & Clinical Practice.
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