Body image is something that has always been linked with the era's cultural beliefs. In the Classical Period, namely in Greece, beauty was a full-formed woman, not disproportionate in any aspect, or a proportional man. Whereas, today, this is obviously not the case for the average person. Evidence of this can be seen on magazine covers, on television, and even in music. Models, who are supposed to be people who would look best in a certain clothing, are often in much better shape than those who will be buying the clothes. Some people see this and wish that their own bodies resembled these models. This is an example of how peoples' body-images are affected directly by cultural surroundings.
Even within subgroups of cultures body-image changes. African-Americans and Caucasian American often have different views on what makes a good body type, and it's not a case within skin color. Caucasian Europeans or Africans may have completely differing opinions on the preferred body-image than their cousins across the Atlantic may have. This, also is an example of how cultures, not race, construct body-image.
Within a certain culture, say, American culture, body-image is not only linked to cultural ideals but to economics as well. This is what Michael Rosenwald tries to say in his article titled Why America Has to Be Fat. He gives reasons as to why the economy has allowed and will continue to allow obesity in America. The way our culture and economics intertwine is conducive to a body-image crisis among the people while it sustains the opposite image through economics.