Final answer:
White females from Western societies are more likely to report dieting in early adulthood due to cultural factors and societal influences.
Step-by-step explanation:
The demographic group that is more likely to report dieting in early adulthood is White females from Western societies. Research has shown that females between the ages of 15 and 19 are most at risk of developing eating disorders.
These disorders, such as anorexia and bulimia nervosa, are culturally-bound phenomena that have been linked to societal messages of a thin ideal often portrayed in popular media and the fashion world.