For screenreader users who are blind or visually impaired (VI), today's mobile devices, while reasonably accessible, are not necessarily efficient. This inefficiency may be especially problematic for microinteractions, which are brief but high-frequency interactions that take only a few seconds for sighted users to complete (e.g., checking the weather or for new messages). One potential solution to support efficient non-visual microinteractions is on-body input, which appropriates the user's own body as the interaction medium. In this paper, we address two related research questions: How well are microinteractions currently supported for VI users? How should on-body interaction be designed to best support microinteractions for this user group? We conducted two studies: (1) an online survey to compare current microinteraction use between VI and sighted users (N=117); and (2) an in-person study where 12 VI screenreader users qualitatively evaluated a real-time on-body interaction system that provided three contrasting input designs. Our findings suggest that efficient microinteractions are not currently well-supported for VI users, at least using manual input, which highlights the need for new interaction approaches. On-body input offers this potential and the qualitative evaluation revealed tradeoffs with different on-body interaction techniques in terms of perceived efficiency, learnability, social acceptability, and ability to use on the go.