The living standards embraced by today's population causes people to consume more resources, which in turn produces more waste and raises life expectancy. New industrial developments have provided a sense of stability and a lot more jobs for the people in their surrounding communities. Also, the increase in wages has allowed people to have larger families because they are able to support them financially. Statistics show that a child born in the U.S. today will produces 52 tons of waste and consume 11 million gallons of water by the age of 27. ("World Overpopulation Awareness" 2001) This is only one person; imagine what the numbers would look like for the entire population. Certain illnesses and diseases can be linked to the exposure the abundant amount of waste products and have a tendency to be more devastation and promenade in overpopulated areas.
Fortunately, advances in the medical field, better doctors and new medications have all played a part in the decrease of these illnesses and have increased the life expectancy for people today
References: The Population Reference Bureau site provided this fact about the population (http://www.prb.org/datafind/datafinder5.htm) The World Overpopulation Awareness site provided statistics about life expectancy http://www.overpopulation.org/