Body image is a person's perception of his or her physical appearance. A person with a poor body image will perceive his or her own body as being unattractive or even repulsive to others, while a person with a good body image will see him or herself as attractive to others, or will at least accept his or her body in its current form. Perceived body image is not necessarily related to any objective measure or the average opinion of other people; a person who has a poor body image may be rated as beautiful by others, and a person with a good body image may be rated as unattractive by others. Body image is most strongly affected during puberty.

Research: measuring body image

Body image is often measured by asking the subject to rate his or her current and ideal body shape using a series of depictions. The difference between these two values is the amount of body satisfaction. Unfortunately, this method does not take into account the fact that a person might be aware of being under- or overweight and also satisfied with that circumstance. Consequently, an obese person, whose obesity causes him or her no psychological distress, might be rated as "having a poor body image" simply because he or she is aware of being obese.

Numerous studies have been undertaken to study body dissatisfaction in recent years. Typically, the research indicates that 33% of men and 70% of women rate their current figure as at least slightly larger than ideal and that body dissatisfaction among women is much larger than for men. These numbers suggest that U.S. women are more aware of what a healthy body weight is, since about two-thirds of Americans are at least somewhat above their healthiest weight. Subsequent studies on this issue have justified this idea, as men whose body mass index puts them in the overweight category often think their weight is in the ideal range, and that those who are clinically obese often believe themselves to be merely overweight.

Some research has been undertaken to determine generational differences in body shape preferences by analyzing body size dissatisfaction for children, adolescents, and adults; significant differences between the age groups have been found. The ideal body mass increases as women get older, which in turn decreases the degree of body dissatisfaction. These cohort differences are a confirmation of the recent increase in body dissatisfaction and eating disorders among young women.

In one form or another, marriage is found in nearly every society. The very oldest records that refer to it speak of it as an established custom. Despite attempts by anthropologists to trace its origin (such as the hypothesis of primitive promiscuity), evidence is lacking. In Western societies, marriage has traditionally been understood as a monogamous union between a man (husband) and a woman (wife), while in other parts of the world polygamy has been a common form of marriage. Usually this has taken the form of polygyny (a man having several wives) but a very few societies have permitted polyandry (a woman having several husbands).