Immigration can increase life expectancy in host countries.

I ask a few questions to Google AI wondering how various policies might effect deathrates.

There is an estimate that cuts in USAID could lead to 14 million more deaths between now and 2030.

Then I wondered about whether restrictions on immigration cause an increase in deaths; especially in countries that people are immigrating from. Answers were a bit inconclusive, but I found out an interesting thing.

Deathrates go down in the countries that people immigrate to. In other words immigration to countries, like USA, lower the death rate here. People who make the journey to immigrate tend to be healthier than domestic population. This is the opposite of what many conservatives think when they talk about all the sick people, supposedly, coming to USA. The immigrant population tends to be healthier than native population.

Still, I think the population growth has other negative effects such as increased traffic due US transportation systems based on private automobile ownership. More people could be accommodated here if our lifestyles and planning were more based on alternative transit.

Apparently, around the 1890s and early 1900s, the increased health effect of immigration was not as evident as it is today. European immigrants, coming to USA in those years, suffered from diseases based on crowded tenements in early US industrial cities. 1918 flu epidemic had an effect on that. Some of these results were inconclusive, however.

Maybe that is why there is the perception of unhealthy immigrants. Of course there are always exceptions to every trend.

Health standards are higher, today so the negative health effects of crowded cities has diminished in recent decades, I assume.

Meanwhile we now have the problem of sprawl; rural areas that are getting too crowded for rural planning. For instance areas that are too crowded for septic tanks to work without contaminating groundwater while still being too sparse for sewer systems to be economically viable.

In towns and cities, it makes sense to have a sewage system, but in spread out rural areas, it costs too much. Rural areas are okay with septic tanks until they get a bit too crowded, then they have problems, but they are still too spread out for centralized sewage systems to be viable. It's the cost of laying out sewer and water system pipes to residents spread way apart.

I remember studying these problems in college planning classes way back in the 1970s. It's the problematic "urban / rural" transition zone. Those areas also have a lot home loss due to forest fires encroaching on residential areas. They tend to have problems with traffic congestion as well.

More compact cities and towns tend to accommodate populations in a better way. A lower footprint on the environment as well. Modern sanitation and other building safety improvements has made urban living safer, I'd guess, than especially back in the early 1900s.