Health & Science: U.S. life expectancy steadily growing

The U.S. government has recently announced that American citizens can expect to live to an average age of 77.9 years old. The good news is that the average lifespan in America has been steadily increasing since the 1950s, and experts are attributing this trend to advances in medicine and lifestyle improvements. Alzheimer's disease and Parkinson's disease continue to take heavy tolls on average lifespan figures, but that hasn't stopped the likes of Edna Parker (born in 1893), Bertha Fry (born in 1893), and other supercentenarians in North America from living well past the 100-year mark.

Humans have been searching for ways to increase lifespan since the neolithic age, when a 20-year lifespan was expected. Life extension sprung to the forefront of nearly everyone's minds in the Middle Ages, when most of Europe was suffering from the plague. Several hundred years later, the subject came up again when Ponce de Leon famously scoured the newly discovered Floridian peninsula in search of the Fountain of Youth. Throughout thousands of years of desperate pursuit, however, most attempts at extending lifespan have floundered.

Biologically speaking, everything that lives must die. To understand the limiting factors of life requires an intimate knowledge of the aging process. Some theories describe an evolutionary reason, wherein organisms have evolved to age given the low likelihood of predation and disease.

Molecularly, studies have indicated that certain genes may limit the lifespan of cells. Other studies cite that unwieldy, ubiquitous oxygen molecules and sugars may deteriorate the innards of cells, causing them to die. Others still suggest that age brings about "wear and tear" that disables normal biological repair strategies.

Advances in biology over the past few decades have permitted scientists to set forth on a series of amazingly complex experiments to get to the bottom of aging. So far, the only proven method for life extension in humans is calorie restriction. Simply controlling calorie intake has led rodents to experience near 50 percent increases in lifespan, and case studies suggest the same holds true for humans.

Other promising but only partially proven methods include reducing biological toxins (including oxygen-free radicals) through the use of antioxidants, certain minerals, and new-age drugs. Other methods include repairing damaged cells through superactive repair enzymes.

Another interesting theory involves the telomeres of chromosomes. Telomeres are the "ends" of the chromosomes. Each time a cell replicates, the telomeres shorten slightly. This process continues until the telomeres are reduced to nothing, resulting in a finite number of multiplications. Possibly lengthening the telomeres may create forever-multiplying cells.

It is important to emphasize the necessity of "controlled" growth when speaking in terms of anti-aging. It has long been known that certain cells will grow indefinitely with no inhibitions whatsoever.

Before getting your hopes up, consider that those cells are cancerous. Current anti-aging therapies, if not thoroughly tested, could allow very aggressive forms of cancerous cells to ravage the body if left unchecked.

Life extension has serious implications for humans as a species. We no longer live in fear of predators or common colds. Our enemies now are internal; self-limiting cellular features. In order to live longer, we'll need to reprogram our genes to allow us to do so. I can't say that we'll ever live indefinitely, but we're certainly on the path to longer, healthier lives.