Rising Population: More Medical Challenges

There's more of us than ever before this morning, as the estimated United States population hit the 300 million mark.

Less than 40 years ago, it was 200 million. It's projected that 400 million will be hit during the decade of the 2040s.

Though just an estimate, based on birth and death and immigration rates, 300 million is a milestone for the country.

On The Early Show Tuesday, medical correspondent Dr. Emily Senay told co-anchor Harry Smith the Census Bureau raises its population estimate by one every 11 seconds, based on a formula that projects a birth every 7 seconds, a death every 13 seconds, and a new immigrant every 31 seconds.

The U.S. has about 4.5 percent of the world's population, Senay points out, and third worldwide, more than a billion people behind China and some 800 million behind India. Indonesia is in fourth place, roughly 50 million behind the U.S.

Of the 300 million people in the U.S., 51 percent are female and 49 percent are male.

And, in a development that could have a major impact on the nation's overall health, 12.1 percent, or more than 36 million Americans, are now 65 or older. With the baby boom generation just reaching age 60, the percentage of Americans who are older will be headed much higher in years to come. That's a lot of people almost certain to need ever-increasing amounts of medical care.

Senay also notes that, by at least one important measure, Americans aren't doing as well medically as you might think: The U.S. ranks 48th in an estimate of life expectancies in countries around the world compiled by the CIA. Someone born in this country this morning is expected to live on average about 77 years and 10 months. That's about two months less than someone born in Bosnia in central Europe, and more than three years less than a child born in Singapore or Japan. Canadians live, on average, more than two years longer than Americans.

If the U.S. indeed reaches 400 million in the 2040s, that would mean one-third more people than live in the country now. That's a lot more people who will need to be fed, and clothed, to have their homes heated and cooled and, of course, to be provided with health care.

How well we handle those tasks as a country could determine just how good a fit all those millions of people turn out to be, Dr. Senay concludes.