Concern about financial conflicts crowds out sufficient consideration of other interests that may bias research conduct. Regulations, institutional policies, and guidance from professional bodies and medical journals all primarily focus on financial ties. But why? Economic gain is not the only powerful influence. This article argues that we under-prioritize non-financial interests in the regulation of medical research. It critiques the usual reasons given for regulating financial and non-financial interests differently — that the interests contrast in terms of tangibility, that financial (...) interests are optional, and that financial interests can be efficiently carved out as a discrete area of focus. Moreover, disparate regulatory treatment seems inattentive to the very similar social and psychological forces that animate the bias effect of both financial and non-financial interests and fails to account for how financial and non-financial interests synergistically interact. Under-prioritization of non-financial interests threatens to erode public trust and creates negative spillover effects that weaken financial conflicts regulation. Optimal regulation requires a more integrated, balanced, and proportionate response to secondary interests in medical research. (shrink)