Not an easy answer, but I'll use some statistics.
"King County, Washington, which includes the city of Seattle, is tackling obesity and tobacco use throughout the community. The combined percentage of overweight and obese adults in the county has increased over the past decade and is currently
55.5%" (CDC)
The percentage that was actually obese in the metro was 22.8%,
Obesity Rates for States, Metro Areas
https://www.cdc.gov/nccdphp/dch/prog...ing-county.htm
Vancouver and neighbouring areas seem to range around 15 - 20% obesity - similar but a bit less.
https://globalnews.ca/news/1362940/k...-stats-canada/
This link below shows that the Vancouver area residents who live near mountains are way more likely to get the requisite amount of exercise every week. Seattle doesn't have areas like that right adjacent to urban neighbourhoods so that's probably a point in Vancouver's favour too. It also seemed to show that commuting by transit was a benefit to health vs. commuting by car. Vancouver has a way higher transit commute share compared to Seattle (about double).
https://www.myhealthmycommunity.org/