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Overview of Sexuality


George R. Brown

, MD, East Tennessee State University

Reviewed/Revised Apr 2021 | Modified Sep 2022

Sexuality is the way in which people experience and express the instincts and feelings that make up physical attraction for others. It is a normal part of human experience and is determined by several different factors, including genetic makeup, childhood upbringing, influences of those around us, and societal attitudes. As such, 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 interest in sex and the frequency of or need for sexual release throughout life. Some people desire sexual activity several times a day, but others are satisfied with infrequent activity (for example, a few times a year). 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.

Concepts of Sex and Gender

Various terms are used to talk about sex and gender. Sex and gender are not the same thing.

  • Sex refers to a person's biologic status: male, female, or intersex.

  • Sexual identity refers to the sex to which a person is sexually attracted (if any).

  • Gender refers to a person's public, lived role as boy or girl, man or woman.

  • Gender identity is the subjective sense of knowing to which gender one belongs; that is, whether people regard themselves as male, female, transgender, or another identifying term (for example, genderqueer, nonbinary, agender).

  • Gender role is the objective, public expression of gender identity and includes everything that people say and do to indicate to themselves and to others the degree to which they are the gender with which they identify.

Some adolescents struggle with the issue of sexual identity and may be afraid to reveal their sexual identity to friends or family members. Helping adolescents put sexuality and sexual identity into a healthy context is very important. Adolescents and their parents should be encouraged to speak openly regarding their attitudes toward sex and sexuality. Parents' opinions remain an important determinant of adolescent behavior in spite of the influences of social media and internet sources of information.

Gender dysphoria Gender Dysphoria Gender dysphoria is having feelings of significant distress or difficulty functioning related to a persistent feeling that a person's sex at birth does not match their inner sense of self as... read more involves a person's strong persistent feeling that their anatomic sex does not match their inner sense of self, or gender identity. This feeling of mismatch causes significant distress or greatly impairs the person's ability to function.

Changing Attitudes about Sex and Sexuality

Societal attitudes about sexuality and gender and what is acceptable vary greatly among cultures and have undergone radical change in some societies. Many people have become more comfortable with their own gender identity (how they present themselves to the world) and with engaging in sexual activities that might have been considered unacceptable in the past. As a result, social norms have been redefined, as illustrated by the following examples of attitude changes in Western culture over recent years.


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 Development of Sexuality and Gender During adolescence, children become young adults. They undergo striking physical, intellectual, and emotional changes. However, the path to adulthood is not a straight line. Adolescents do not... read more ).

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 Human Immunodeficiency Virus (HIV) Infection Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and is treated with antiretroviral medications. If untreated, it can cause... read more Human Immunodeficiency Virus (HIV) Infection , herpes simplex Herpes Simplex Virus (HSV) Infections Herpes simplex virus infection causes recurring episodes of small, painful, fluid-filled blisters on the skin, mouth, lips (cold sores), eyes, or genitals. This very contagious viral infection... read more Herpes Simplex Virus (HSV) Infections , hepatitis Overview of Hepatitis Hepatitis is inflammation of the liver. (See also Overview of Acute Viral Hepatitis and Overview of Chronic Hepatitis.) Hepatitis is common throughout the world. Hepatitis can be Acute (short-lived) read more , syphilis Syphilis Syphilis is a sexually transmitted infection caused by the bacteria Treponema pallidum. It can occur in three stages of symptoms, separated by periods of apparent good health. Syphilis... read more Syphilis , gonorrhea, Gonorrhea Gonorrhea is a sexually transmitted infection caused by the bacteria Neisseria gonorrhoeae, which infect the lining of the urethra, cervix, rectum, or throat, or the membranes that cover... read more Gonorrhea and human papillomavirus, which causes cervical cancer Cervical Cancer Cervical cancer develops in the cervix (the lower part of the uterus). Most cervical cancers are caused by human papillomavirus (HPV) infection. Cervical cancer usually results from infection... read more 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 infections Overview of Sexually Transmitted Infections (STIs) Sexually transmitted infection (STI) refers to an infection that is passed through blood, semen, vaginal fluids, or other body fluids during oral, anal, or genital sex with an infected partner... read more Overview of Sexually Transmitted Infections (STIs) to unsuspecting spouses or sex partners.

Sexual Problems

When sexual feelings, behavior, or dysfunction cause 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. For example, people who have frequent, intense, sexually arousing fantasies or behaviors that involve inanimate objects, children, or nonconsenting adults or that involve suffering or humiliation of oneself or the partner (paraphilias Overview of Paraphilias and Paraphilic Disorders Paraphilias are frequent, intense, sexually arousing fantasies or behaviors that involve inanimate objects, children or nonconsenting adults, or suffering or humiliation of oneself or the partner... read more ) may feel distressed by the paraphilia and seek or be referred for treatment.

Sexual problems may have physical causes, psychologic causes, or both. Problems with sexual function can affect both men and women. Men may experience decreased libido Decreased Libido in Men Decreased libido is a reduction in sex drive. Possible causes include psychologic factors (such as depression, anxiety, or relationship problems), drugs, and low blood levels of testosterone... read more , erectile dysfunction Erectile Dysfunction (ED) Erectile dysfunction (ED) is the inability to attain or sustain an erection satisfactory for sexual intercourse. (See also Overview of Sexual Dysfunction in Men.) Every man occasionally has... read more , the inability to ejaculate Inability to Ejaculate Inability to ejaculate (anejaculation) is usually caused by inability to reach orgasm (anorgasmia). It usually occurs as part of erectile dysfunction. (See also Overview of Sexual Dysfunction... read more , or premature ejaculation Premature Ejaculation Premature ejaculation is ejaculation that occurs too early, usually before, upon, or shortly after penetration. The cause is most likely to be anxiety, other psychologic factors, or very sensitive... read more . Women may experience low sexual interest Sexual Interest/Arousal Disorder Sexual interest/arousal disorder is lack of or decreased interest in sexual activity and sexual thoughts and/or lack of response to sexual stimulation—mental or emotional (subjective) and/or... read more or a sexual arousal disorder Sexual Interest/Arousal Disorder Sexual interest/arousal disorder is lack of or decreased interest in sexual activity and sexual thoughts and/or lack of response to sexual stimulation—mental or emotional (subjective) and/or... read more , pain during sexual intercourse (genitopelvic pain/penetration disorder Genitopelvic Pain/Penetration Disorder Genitopelvic pain/penetration disorder includes pain during sexual intercourse or other sexual activity that involves penetration and involuntary contraction of muscles around the opening of... read more ), or problems with orgasm (female orgasmic disorder Orgasmic Disorder in Women Orgasmic disorder is lack of or delay in sexual climax (orgasm) or orgasm that is infrequent or much less intense even though sexual stimulation is sufficient and the woman is sexually aroused... read more ). Sexual problems tend to be more common among older people. Many of these problems can be effectively treated.

People's sexual problems can be influenced by their 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

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