Objective Early psychosomatic research proposed a hydraulic model for anger expression and blood pressure (BP); that is, people who express their anger were believed to have lower BP. Unfortunately, subsequent evaluations of this model have produced inconsistent results. In this paper, it is posited that weak methods of measuring BP, failure to address gender differences, and exclusive emphasis on linear models may have contributed to inconsistent results. Design and measures We investigated the possibility of curvilinear relationships between expressed anger and resting BP after controlling for traditional risk factors. Participants Data from two samples of varying cardiovascular health status (one healthy, the other hypertensive) and ages were examined. Results Across both samples, very low and very high self-reported expressed anger was associated with the lowest diastolic BP in women. There was no equivalent finding in men. Conclusion Women, but not men, have lower BP when they report to openly express their angry feelings. The results support the value of exploring curvilinear relationships and gender differences in anger expression effects on cardiovascular health.