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Overview of Sexuality


George R. Brown

, MD, East Tennessee State University

Last full review/revision Aug 2019| Content last modified Aug 2019
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Sexuality is a normal part of human experience. However, the types of sexual behavior that are considered normal vary greatly within and among different cultures. In fact, defining “normal” sexuality may be impossible. There are wide variations in people’s sexual behavior, including the frequency of or need for sexual release. Some people desire sexual activity several times a day, but others are satisfied with infrequent activity (for example, a few times a year).

However, when sexual behavior causes significant distress for a person or the person's partner or harms another person, the person may need to be evaluated by a health care practitioner and treated.

Although younger people are often reluctant to view older people as sexually interested, most older people remain interested in sex and report satisfying sex lives well into old age. Problems with sexual function, such as erectile dysfunction in men and pain during sexual intercourse (dyspareunia), painful spasm of vaginal muscles (vaginismus), or problems with orgasm in women, affect people of all ages. However, such problems tend to be more common among older people. Many of these problems can be effectively treated with drugs (most notably those for erectile dysfunction).

A person’s attitude toward sexual behavior is influenced greatly by parents, who can damage their children’s ability to develop sexual and emotional intimacy by doing things such as the following:

  • Being emotionally distant

  • Punishing children too severely

  • Being overtly seductive and exploiting children sexually

  • Being verbally and physically hostile

  • Rejecting children

  • Being cruel

Societal attitudes about sexuality and gender change with time, as illustrated by the following.


Once regarded as a perversion and even a cause of mental disease, masturbation has now long been recognized as a normal sexual activity throughout life. About 97% of males and 80% of females have masturbated. In general, males masturbate more frequently than females. Many people continue to masturbate even when they are involved in a sexually gratifying relationship. Although masturbation is normal and is often recommended as a safe sex option, it may cause guilt and psychologic suffering that stems from the disapproving attitudes still held by some people. These feelings can result in considerable distress and can even affect sexual performance.


As with masturbation, homosexuality, once considered abnormal by the medical profession, has not been considered a disorder for more than four decades. It is widely recognized as a sexual orientation that is present from childhood. An estimated 4 to 5% of adults are involved exclusively in homosexual relationships throughout their lives, and an additional 2 to 5% of people engage in sex with people of either sex (bisexuality). Adolescents may experiment with same-sex play, but this experimentation does not necessarily indicate an enduring interest in homosexual or bisexual activity as adults (see Development of Sexuality).

Gay and lesbian people discover that they are attracted to people of the same sex, just as heterosexuals discover that they are attracted to people of the opposite sex. The attraction appears to be the result of biologic and environmental influences and is not a matter of choice. Therefore, the popular term “sexual preference” makes little sense in matters of sexual orientation, whether the orientation is heterosexual, homosexual, or bisexual.

Frequent sexual activity with different partners

For some heterosexuals and homosexuals, frequent sexual activity with different partners is a common practice throughout life. In Western cultures, this behavior has become more acceptable. However, having many sex partners is linked to the transmission of certain diseases (such as HIV infection, herpes simplex, hepatitis, syphilis, gonorrhea, and cervical cancer) and may also signify difficulty in forming meaningful, lasting intimate relationships.

Extramarital sex

In the United States, most people engage in sexual activity before they are married or while they are not married. This behavior is part of the trend toward more sexual freedom in developed countries. However, most cultures discourage married people from engaging in sex with someone other than their spouse. This behavior occurs frequently despite social disapproval. One objective problem that results is the possible spread of sexually transmitted diseases to unsuspecting spouses or sex partners.

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