Being overweight or obese puts a person at greater risk for a wide variety of serious health problems. Obesity is recognized as a national problem that has grown tremendously over the last three decades, contributing to increases in medical expenditures for treatment of related diseases.

In 2019-21, 71% of residents in Lancaster County were either overweight or obese, which was higher than the state and nation (both at 67%). The county's percentage has increased 5 points from 2011-13. Pennsylvania's rate increased by 2 percentage points and the U.S. rate increased by 3 percentage points during the same period.

The percentage of overweight and obese residents in Lancaster County in 2019-21 was higher than in all the comparison counties. Of the comparison counties, Chester County had the lowest percentage of overweight or obese residents at 59%.

Similar to Lancaster, Cumberland/Perry saw a 4 point increase in the percentage of overweight and obese residents since 2011-13, while Berks/Schuykill saw a 2 point increase. Chester and York remained unchanged and Dauphin/Lebanon saw a decrease of 2 points in the same time period.

Data come from a federal government survey designed to collect scientific data on health risks and behaviors. The data reported are for moving three-year averages. Berks and Schuylkill county data is combined by the survey and reported together. Similarly, Dauphin and Lebanon counties and Carbon, Lehigh, and Northampton counties are reported as groups of counties.

Beginning in 2011, the Centers for Disease Control made two changes to the Behavioral Risk Factor Surveillance System on which this indicator is based. The survey now includes cell-phone users, and a new statistical method is used to weight responses. As a result, changes from 2010 and years prior to 2011 and later may be a result of those technical changes rather than true trends.