Medical anthropologist Paul Farmer argues that the major flaw in the dominant model of medical care in the US is that medical services are sold as a commodity, remaining only available to those who can afford them. As medical professionals are not trained to understand the social forces behind disease, nor are they trained to deal with or alter them, they consequently have to ignore the social determinants that alter access to care. As a result, medical interventions are significantly less effective in low-income areas. Similarly, many areas and even countries cannot afford to stop the harmful cycle of structural violence.