A recent Spanish survey found that 62 percent of men and 37 percent of women over the age of 65 are sexually active.
The survey, which consisted of nearly 2,000 people, also found that the kisses, caresses and vaginal penetration, were among the most common practices for older adults, and masturbation and oral sex were the least practiced sexual acts in this age group.
The findings show that the main causes of sexual inactivity were physical illness and widowhood.
Other factors that contribute to sexual inactivity in both sexes were being older than 75, not having a partner, having a low level of education and poor perception of their own health and sexuality, suffering from two or more chronic illness and taking two or more types of medication.
"This research lets us know the reality of a social phenomenon which is not tackled enough in Spain: sexuality and the elderly", lead author Domingo Palacios of the Rey Juan Carlos University in Madrid said in a statement released on Wednesday.
Palacios said that the findings can be applied to disease and illness prevention and to promote health and healthy sexual practices.
The study is published in the Journal of Sexual Medicine.
A previous study in 2006 found that 60 percent of people in Spain over the age of 65 reported having sex four times a month, and while the majority said that their sexual intercourse had changed due to aging, sex was still just as satisfying.
Another study published in the New England Journal of Medicine in 2008 found that 73 percent of Americans between the age of 57 and 64 are sexually active, compared to 53 percent for those aged between 65 and 75 and 26 percent for those aged 85 percent.
Sexually transmitted diseases are also on the rise among older adults.
A December report, published in the journal MEDSURG Nursing, found that rates of HIV/AIDS, herpes, syphilis, human papilloma virus (HPV), and other STDs are climbing for people over the age of 50.
Rates of HIV/AIDS have jumped from 17percent in 2001 to 24 percent in 2005, and for other STDs the Centers for Disease Control showed in an annual 2004 to 2005 report that syphilis, chlamydia and gonorrhea have increased in people over the age of 40.
The rise in STDs suggest that people in this age group are more sexually active than previous generations to more liberal sexual attitudes, high divorce rates and an increased use of online dating services.
"Unfortunately, the common misconception still persists that people over 50 are no longer sexually active," wrote co-authors Lisa Jeffers and Mary DiBartolo in the December report "As a result, health care providers often do not discuss risky sexual behaviors and STD prevention with middle-aged and older adults."
Experts urge health care professionals to help patients feel comfortable about discussing sexual matters, educate them about risks, and provide thorough physical assessments and screening tests.