Cultural expectations that guys have to be nonchalant when it comes to their physiques makes body dissatisfaction in boys more difficult to assess, but there is little doubt they are affected by media representations of idealized masculinity. In addition, as advertisers increasingly turn their attention to young men as a lucrative demographic, it is unlikely that such representations are going to disappear any time soon.
Body dissatisfaction amongst boys and young men is fuelled not just by the idealized male bodies they see in media, but also by the idealized images of women that are represented. A 2008 study found that young men were more self-conscious about their bodies after reading "lad magazines" featuring photos of sexualized, scantily-clad women, based on the belief that girls would expect similar idealized physiques from men as well.  Other research has found a relationship between the increase in idealized male bodies in media and the rise in body dissatisfaction and weight disorders in boys and young men: a 2005 study, for instance, found that media influence had the largest effect on whether middle-school boys were dissatisfied with their bodies. 
The increase in eating disorders in male adults is well-established. A study by the UK National Health Service found that hospital admissions for men with eating disorders had risen by two-thirds between 2001 and 2011.  Eating disorders are also on the rise amongst boys, particularly athletes.  There are also concerns that some boys – some as young as age 10 – are becoming obsessed with building a muscular physique,  a condition that is thought to be related to changes in how muscular male sex symbols have become over the last few decades.  This obsession may take the form of fixation with exercise, particularly weightlifting; abuse of anabolic steroids and other performance-enhancing drugs, which may damage the heart, liver, kidneys and immune system; and muscle dysmorphia, whose sufferers see themselves as thin and weak no matter how well-muscled they become. 
While the desire to be more muscular has been the focus in most of the research on body image issues among boys, recent evidence suggests that rather than focusing on building muscle mass boys are most likely to focus on achieving or maintaining an average weight that is neither over- nor underweight, to avoid standing out from their peers.  As a result, boys who are unhappy with their bodies are almost equally likely to be concerned about being too thin as being too fat.  This suggests that the level of eating disorders and other body image issues may be higher than is currently thought, since researchers have traditionally measured body dissatisfaction in boys based on their desire for a more muscular build. It also suggests that interventions based on those that have been designed for girls may be less effective with boys: for instance, researchers found that BodiMojo, a website designed to help youth deal with body image issues, had positive results with girls but not with boys. 
This may be because while girls are typically open about being concerned with their bodies in general and weight in particular, boys are under pressure to avoid being too skinny or heavy without seeming to care about how they look.  Julia Taylor, a counselor at a North Carolina high school and author of Perfectly You, describes her experience at a body image awareness event: "Guys did not even want to go near our table," she says, but when she left the table boys "would look at it, then walk away, then come back and fold up a pamphlet real quickly and put it in their pocket."  Parents, teachers and counselors need to be more aware of the prevalence of body image issues among boys, and not wait for them to openly seek help;  as well, while boys need to be educated and provided with the same sorts of tools as girls, they need materials that are specifically designed for them  that not only address their particular concerns (both the drive to muscularity and the pressure to not stand out on the basis of weight) but are delivered in a way that boys can access them privately, away from the eyes of their peers.
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