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Numbers are used to instruct, inform, and give meaning to information in order to help us make better judgments and healthier choices in our everyday lives. However, research has demonstrated that not all people can understand and use numbers effectively. In particular, people differ in numeracy. Among uninsured adults, we estimated that 28.8 % are at a Below Basic level of numeracy, 33.4 % are at a Basic level, 29.3 % are at an Intermediate level, and only 8.6 % are at a Proficient level of numeric literacy. Numeracy skills needed to select a health plan, choose treatments, and understand medication instructions include education-based skills and emergent decision-based abilities. We estimate that the skills needed to make many complex informed health decisions (e.g., management of chronic diseases) require a Proficient level of numeric literacy, given how numeric information is often provided. However, if health information providers present information to patients and consumers in an evidence-based manner, a greater proportion of the population will be successful in making informed health and health-related decisions. We identify five main communication themes and discuss evidence-based strategies for communication under each theme.