Social allostasis, the process by which social interactions dynamically regulate psychophysiological states (e.g., emotions), is attracting attention. Social allostasis can significantly impact people's mental and physical wellbeing. However, adaptive social relationships are not necessarily available to all people. The use of robots is expected to solve this problem. In this paper, we present three studies of our group that prove the influence of social interactions with robots on human psychophysiological states. Our results showed that robots could amplify human subjective and physiological emotional responses through conversation, touch, and television co-viewing experiences. These results suggest that robots may be helpful for adaptive social allostasis regulation.