Published: Jun 16, 2011 3:57 PM EDT
Updated: Jun 15, 2011 10:04 PM EDT

COLLIER COUNTY, Fla. - If you've ever wondered where in the United States people are living the longest, you don't have the look very far. Women in one Southwest Florida county are topping the charts.

William Shakespeare once said, "A light heart lives long."

A new study shows Collier County women have the highest life expectancy in the nation, on average, living to the ripe age of 86.

'I've never felt happier and healthier since I moved to Southwest Florida," Liz Barrett said.

"There's generally high disposable income in Collier County," Dr. Daniel Kaplan said. "Certainly has to do with the ability to purchase better quality, higher quality foods. It also has to do with education and understand what types of foods may be more healthy for you>"

But the outlook isn't so bright everywhere. The U.S. ranks  37th in the world for life span, down from 20th in 1987.  The report shows, in 737 out of more counties, womens' life expectancies declined between 1997 and 2007, while mens' increased. And in some parts of the U.S., men and women are dying younger than their counterparts in Vietnam, Syria and Panama. Experts blame obesity, high blood pressure, and smoking.

"Typically in the big city, especially in areas that don't have great disposable income, they tend to eat large quantities of simple carbohydrates," Kaplan said.

So what is it about places like Naples or Marco island? Dr. Kaplan says there's no fountain of youth flowing here, it's all about healthy diets and exercise.

"No matter what county, no matter what state, certainly the sunshine down here is helpful promoting vitamin D," Kaplan said.

"It's clean, it's relaxing, it's a place you don't feel stressed," Christina Crider said.

"I can't wait for us to grow old together," Christina's husband John Crider said.

The average life expectancy for women in Collier County rose nearly 6 nears from 1987, putting them ahead of Spain, Switzerland and France.

To read the entire study go to: http://www.healthmetricsandevaluation.org/news-events/news-release/life-expectancy-in-us-counties-2011