How do consumers interpret labeling statements claiming the nutritional or health benefits of a food product? What impacts do these statements have on how consumers make shopping decisions? These are important questions for regulators, the industry, and nutrition educators and professionals in communicating with consumers about food labels and dietary choices. To help provide consumers more and better information about foods, the US Food and Drug Administration conducted an Internet study from January to March 2006 to understand the causal relationships between health claims and other health messages and consumer responses. The study suggests that consumers have different levels of familiarity with different nutrients and diet-disease relationships. Both consumer familiarity with a nutrient or diet-disease relationship and the type of health message can affect consumer interpretation of health messages and their perceptions of products. More detailed health messages seem to have stronger impacts on consumers when the nutrients or diet-disease links are less familiar or unknown.