Generally dated to the 1970s, the 1980s and 1990s witnessed an increase in activist organizations, publications, and conferences. In the 1980s new anti-dieting programs and models began to appear in the research literature, in response to new information dispelling common myths about obesity. The contemporary movement perceives negative societal attitudes as persistent, and based on the presumption that the rotund characteristics of a person's body reflect negative character traits of that person. For example in Chang and Christakis paper they state this belief by stating that obesity is detrimental to the community, by means of decreasing human efficiency, and that obese people interfere with labour productivity (V Chang and N Christakis, 2002). Furthermore, these diet-touting trends and societal views have led to an increase in psychological and physiological problems among those who feel that their weight is above the "socially acceptable norm".
Fat activism covers several fronts but generally can be described as attempting to change societal, internal, and medical attitudes about fat people.
The movement argues that large people are targets of hatred and discrimination, with obese women in particular subject to more social pressure. Hatred is seen in multiple places including media outlets, where fat people are often ridiculed or held up as objects of pity. Discrimination comes in the form of lack of equal accessibility to transportation and employment.
Proponents also argue that people of all shapes and sizes can strive for fitness and physical health. Thus, proponents promote "health at every size", an idea that one can place their mental and physical health before physical appearance and size.
Through the works of authors such as Paul Campos and Sandy Szwarc, the fat acceptance movement has argued that doctors should treat health problems of people of all sizes, recognizing that health issues are not defined by weight and are shared by people of all sizes, fat and thin. Some in the movement have argued that the health risks of fatness and obesity have been greatly exaggerated, and used as cover for cultural and aesthetic prejudices against fat.
Fat activism faces challenges. Organizations such as the National Association to Advance Fat Acceptance (NAAFA) and the International Size Acceptance Association (ISAA) are small in number, and people interested in the movement tend to be clustered in larger cities and spread across medium- to small-sized web communities. NAAFA changed leadership around the turn of the century.
The history of this movement is difficult to chart because of its grassroots nature, although it originated in the late 1960s and 1970s. Like other social movements from this time period, the fat acceptance movement, initially known as "Fat Pride," "Fat Power," or "Fat Liberation," often consisted of people acting in an impromptu fashion. To offer one example, a "Fat-in" was staged in New York's Central Park in 1967. Called by a radio personality, Steve Post, the "Fat-in" consisted of a group of 500 people, eating, carrying signs and photographs of Sophia Loren (an actress famous for her figure), and burning diet books.
Several groups were formed in this period that promoted a fat acceptance agenda. The "Fat Pride" group, NAAFA, initially called the National Association to Aid Fat Americans, subsequently renamed the National Association to Advance Fat Acceptance, was begun in 1969 by William Fabrey. This group was at its inception more of a social club. A more radical group, the Fat Underground, was founded in 1973. The group had begun as a chapter of NAAFA, but had quickly developed an activist philosophy more radical than the group. To be more specific, they were inspired by the philosophy of the Radical Therapy Collective, a feminist collective that believed that many psychological problems were caused by oppressive social institutions and practices. The group consisted of a number of members including the founding members Sara Fishman (then going by Aldebaran) and Judy Freespirit, and subsequently Lynn McAffee. They quickly developed into a group that took issue with the developing science against obesity. One of their central sayings, "A diet is a cure that doesn't work for a disease that doesn't exist," reflects their dedication to fat acceptance as well as fat activism.
Shortly afterwards, Fishman moved to New Haven, CT, where she, along with Karen Scott-Jones, founded the New Haven Fat Liberation Front, an organization similar to the Fat Underground in its scope and focus. In 1983, they collaborated to publish a germinal book in the field of Fat Activism, Shadow on a Tightrope. The book consists of some activist position papers, initially distributed by the Fat Underground, as well as collections of poems and essays from other writers.
Today the Fat Acceptance Movement continues to strive for societal, internal, and medical attitude change in regards to fat people. Proponents engage in public education about the myths about being fat and about fat people, conferences and conventions, and in writing newsletters and books.
In recent years there has been an increase in online zines, bloggers, retail items for fat people, and online communities of activists. As well as a steady stream of books by fat activists challenging the medical belief that fat = unhealthy, and highlighting the issue of weight-based discrimination that the fat face by the community and medical professionals. In addition to online and literature there has also been an increase in the arts on sizeism. Performance art groups such as The Padded Lillies, Big Burlesque and the Fat Bottom Revue just to name a few feature a variety of body types in their shows
There has also been an emerging body of fat political and sociological studies, some with a fat activist agenda, developing within the academy. The American Popular Culture Association has an area in fat studies and regularly includes panels on the subject. In addition, student groups with a fat activist agenda have emerged in a number of colleges including Hampshire, Smith, and Antioch colleges.
In addition to what the movement is doing to raise public awareness, there have been a surge in studies both for and against fatness in scientific journals on virtually all topics including medical, psychological, politics, etc.
One point of contention in the movement is found between those fat people who are attempting to lose weight and those who are not. Opponents of weight loss attempts cite the high failure rate of all permanent weight loss attempts, and the many dangers of "yoyo weight fluctuations" and weight loss surgeries.
Due to intrinsic linguistic misunderstandings and differing definitions of the word "acceptance," some "fat activists" believe the phrase refers to any fat person fighting for equal rights and opportunities, regardless of whether or not that person believes that the pursuit of reduction in a person's body mass is feasible. Other "fat activists" define "fat acceptance" more strictly, applying that phrase only to fat people who are not pursuing a reduction in their body mass, and use phrases such as "fat activist" to describe fat people and "allies" working more generally on civil rights issues pertaining to fat people.
An additional issue with regard to language is that many in the fat acceptance movement find the terms "obese" and "overweight" offensive, as they are often used to make overtly prejudiced statements seem more clinical or scientific. The word "fat" is generally preferred.
In practice, the only way to know the position of any particular individual member of the group on weight loss attempts is to ask, or read specific position papers on the issue.
There are many health related problems associated with obesity, including heart disease, diabetes, high blood pressure and joint problems caused by overloading the skeleton with too much weight. One study found that obesity reduces life expectancy. Public health officials regard widespread obesity as posing significant costs to society.
Additionally, the common fat acceptance mantra that "diets don't work" is considered by some critics to be an oversimplification that may discourage a person in need of a healthier lifestyle from making responsible and potentially beneficial changes in eating habits.