There are a few reasons why smaller dogs live longer than larger dogs. u003cbru003eu003cbru003eFirst, smaller dogs have a lower center of gravity, which makes them less likely to topple over. u003cbru003eu003cbru003eSecond, smaller dogs have a higher metabolic rate, which means they burn more calories and thus live longer. u003cbru003eu003cbru003eFinally, smaller dogs have a lower risk of developing health problems like heart disease and arthritis.