Aims: We conducted an intervention study to clarify how effectively a telemedicine system using a multi-functional videophone could be used in lifestyle guidance, with special focus on diet for diabetic patients cared for at home. Methods: Patients were assigned to a 3-month intervention group or to a usual care group. In the intervention group, patients and a medical professional communicated bi-directionally through a videophone-based communication system for 30 min, once a week. The participants were encouraged to send pictures of each meal online, through the videophone system, in real time. Results: In intra-subjective comparison, the 3-month intervention program resulted in a significant decrease in body weight (BW) (p &lt
0. 0005) and average HbA1C level (p &lt
0. 005) compared with before the intervention program. Three months after the conclusion of the intervention program, average HbA1C levels returned to almost the same levels as before intervention (p &lt
0. 05). In the usual care group, average HbA1C level did not change significantly for 6 months. Conclusions: 3-month intensive communication using the multimodal videophone system led to a significant decrease in BW and average HbA1C level. This novel bi-directional communication is useful for improving conditions such as diabetes, BW, and hyperglycemia for homecare diabetes patients, thus, reducing cardiovascular risk. © 2012 The Japan Diabetes Society.