His compatriots might disagree.
Nearly 40% of Buffett's peers -- American men between 75 and 85 years old -- are sexually active, new studies reveal. More than half of those have sex at least twice a month. A quarter do it every week. (Only 17% of women that age are sexually active, but they're equally busy.) That might be more positive transactions than Wall Street is seeing these days.
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For decades, the medical profession politely averted its gaze from such issues as nursing-home libidos and octogenarian onanism. Many doctors -- not to mention patients themselves -- assumed that sex must simply fade away quietly over time and, really, who would miss it?
But now the study of aging and sexuality is gaining interest. (Perhaps those sexually pioneering youths from the '60s, now nearing retirement themselves, have something to do with that?) And the resulting research reveals surprising news: Age itself does not limit our desire and prowess in bed. Rather, the blame goes to aging-related issues -- health problems, medication side effects and a lack of steady partners.
If we manage to stay happy, healthy and socially connected as we get older -- a tall order but not impossible -- chances are good that we can continue to enjoy sex as long as we desire.
Depending on your preferences, that might be a long time indeed. "The oldest person that I ever referred for a penile prosthesis was 98," says Dr. John Morley, geriatrics professor at St. Louis University. "He used it until he was 101, very happily. Our desire to have sex does not have an expiration date."
Our bodies' shelf life keeps extending too. Thirty years ago, medical practice considered people in their 60s to be "old," Morley says. That's almost laughable in geriatrics sex clinics these days. "I never see anyone who's under 70," he says, "and most of the patients I see are 80 and 90."
Thank modern medicine and nutrition. In 1900, the average life expectancy was 47 years. Now it's 75 years for men and 80 years for women. Today's 65-year-olds can expect to live another two decades or so. And it makes sense that we would want to while away some of those extra hours with sex, especially after former libido-busters -- stressful jobs, crying kids, pregnancy worries -- have blissfully disappeared.
But if doctors are going to help us keep our sexuality in good shape, they need to know exactly what we're doing in the bedroom -- and how aging and illness change the picture.
"Until recently, we had very little work done on people after fertility," says Edward Laumann, sociology professor at the University of Chicago and sociology of sex researcher.
That's quickly changing. In 2004, Laumann and other University of Chicago researchers from the National Social Life, Health and Aging Project set out to study the sex lives of "older adults" in the U.S., which they defined as those between the ages of 57 and 85.
Researchers sat in living rooms across America and delicately asked more than 3,000 men and women about a variety of blush-worthy topics: sexual history, masturbation practices, oral sex preference, sexually transmitted diseases and so forth. The participants were carefully chosen to be balanced by race, age, gender and location. Researchers even drew blood and took fluid samples to draw links between physical and sexual health.
This data set will be mined for nuggets of information and trends for years to come. Two reports have been published already: an overview in the New England Journal of Medicine in August 2007 and an initial examination of sexual problems in the Journal of Sexual Medicine in September.
Here's a sampling of recent findings on the sex lives of 57- to 85-year-olds:
* About 69% of men and 40% of women have engaged in some form of sexual activity with a partner in the last year. Even after the age of 75, rates don't plummet: 39% of men and 17% of women remain sexually active.
* The most common reason men and women cite for their lack of sexual activity? Men's physical health. Other top reasons, mentioned by those without a partner, include lack of interest and not having met "the right person."
* More than half of sexually active men and women have sex at least twice a month. This rate doesn't change with age. And nearly a quarter of sexually active 75- to 85-year olds report having sex four times -- or more -- a month.