It's quite well known that younger populations are less demanding on the health care system. To put it otherwise, they cost the public health care system less. As we get older, we tend to cost more in terms of health care services. Provinces or regions with an older population tend to have greater public health care needs. Urban populations that are younger have different challenges, but generally speaking, they tend to need less in terms of health care expenditures.
The Canada health transfer is a per capita transfer that is equal. It does not take into account the differences in demographics across provinces. Provinces receive the same amount per capita, be they older or younger on average. It does not take into consideration the differences in the composition of populations.