How long do you want to live?

How many years would you like to live? Is 50 enough? Or would you like to be around for 60, 70 or 80 or more?

While most of us don't know exactly how long we have to live, recent research backs up a core belief that I have held for many years: Our lifestyle choices influence our lifespan.

The study, published in the journal PLoS Medicine and conducted by the Harvard School of Public Health, says that life expectancy has declined in nearly 1,000 counties, especially for women, "primarily because of chronic diseases related to smoking, overweight and obesity, and high blood pressure."

According to a New York Times story citing the same study, most of the counties with declines are in the Deep South, along the Mississippi River, and in Appalachia, as well as in the southern Plains and Texas.

In the worst-performing counties, all in southwestern Virginia, the drop in life expectancy over the 16-year period was nearly six years for women and two and a half years for men. In the counties showing the greatest improvement, many in the desert West, life expectancy rose nearly five years for women and nearly seven years for men.

This trend reflects the long-term consequences of smoking -- a habit women took up after men did -- and the slowing of the historic decline in heart disease deaths. It may also represent the leading edge of the obesity epidemic, according to the Washington Post.

If that is the case, we ladies can expect our life expectancies to drop significantly across the United States in coming years, ending a nearly unbroken rise that dates to the mid-1800s.

This is not good. Not good at all. The researchers call this decline a "reversal of fortunes."

Aptly put. If we are not making the best choices we can about our diet, exercise and health, then we may be responsible for shortening our own lives.

The Washington Post story cites health trend information that we have seen before, if we've been looking.

But I'll cite it again here, because it seems that we're just not getting it:

• About half of all deaths in the United States are attributable to a small number of "modifiable" behaviors and exposures, such as smoking, poor diet and lack of exercise.


• About 33 percent of women are now obese, compared with 31 percent of men. Extreme obesity is twice as common in women (7 percent) as in men (3 percent).


• Being overweight greatly increases the risk of developing Type 2 diabetes. A national survey in 2002 found that 85 percent of diabetics were overweight or obese.


• In recent years, the prevalence of high blood pressure has been increasing in women, as well -- partly the result of weight gain. In 1990, 42 percent of women older than 60 had hypertension; by 2000 it was 51 percent.

We need to reverse our fortunes back the other way. But can we?

The study's authors argue that their results are troubling because an often-stated aim of the U.S. health system is the improvement of the health of “all people, and especially those at greater risk of health disparities.”

In a 2006 study, the same group concluded that life expectancy disparities would have to be addressed through public health strategies aimed at reducing the risk factors that cause chronic disease and injuries.

Okay, this sounds great, but why wait on them? We can do this as individuals, if only we will. There is enough health information out there that if you just want to badly enough, you can change your lifestyle and get healthier.

Unfortunately, studies like this one make me pessimistic that enough of us really -- I mean really -- want to do what it takes to live a healthier life. How many of us say it's too hard, or that we don't have enough time or money or that we just can't give our favorite foods up?

If you're still using those excuses -- and that's all they are -- then you're not ready to make a lifestyle change.

And if you're not ready to make a lifestyle change, and to listen to what experts like the authors of the Harvard study are telling you, then you are well on your way to shortening your own life.

I realize our choices are not the only factor. There are genetic factors that influence our health as well. We may have a family history of cancer, heart disease, high blood pressure or diabetes.

But our health is not a foregone conclusion, either. We can control whether we succumb willingly to our genetics or whether we go down fighting. Do you want to just throw your hands up and say, "Well, I'm going to get cancer (or diabetes or high blood pressure) anyway, so I may we well eat what I want and not bother"?

Or do you want to fight it?

I choose to fight it.

We make our own health fortunes. What will you choose?