Granger and other researchers in the laboratory are working on various projects that can have major health implications. Saliva tests can be used to measure testosterone levels. Higher levels of testosterone have significant health benefits for some middle-aged men. Men with higher testosterone are less vulnerable to high blood pressure, heart attacks, frequent colds and obesity. In addition, they are more likely to rate their health as excellent or good rather than fair or poor.
Studies show self ratings of health correlate highly with physicians' assessments.
However, some, but not all, men with higher levels of testosterone are more likely to engage in behavior that cancels out the beneficial effects of testosterone, such as being more likely to smoke. Granger is also using saliva assays to test cortisol levels. Cortisol is a hormone linked to stress, anxiety, depression, and socially withdrawn behavior. Granger has shown in past research that children who are more socially withdrawn or anxious are more likely to have an increased level of cortisol in their bodies. This is in response to stresses like social conflicts with their parents.