But I'm not more aggressive—a behavior change often tied to testosterone. That's not surprising to Robert Sapolsky, ., a neuroendocrinologist at Stanford University and a leading researcher on stress and behavior. "It's really not the case that testosterone 'causes' aggressive behavior," he says. "Instead, it makes the brain more sensitive to social cues that trigger aggression. And in support of that, a guy's testosterone level isn't a very good predictor of how likely he is to be aggressive."
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4. You're depressed and/or anxious.
While low testosterone likely isn't the sole cause of anyone's depression, research shows it could also have a hand in the disease. In a study of women, ages 25 to 46, those with low testosterone were more likely to be depressed. Other research shows that women with prolonged testosterone deficiency are often both more anxious and more depressed than women with normal testosterone levels.
5. You have a weak grip.
gettyimages-185463533-weak-grip- psphotograph/getty images
Osteoporosis, which causes weak bones, is often considered a women's disease because low estrogen is a key factor in lost bone density. But research shows that low levels of testosterone can leach strength from your skeleton as well, according to Harvard Health . Both men and women who have low levels of testosterone are considered "frail" partially because they can no longer hold a firm handshake. For most women, lack of estrogen will be the main reason osteoporosis sets in, especially following menopause, when the hormone drops dramatically. But replacing estrogen may not be enough if testosterone is also out of balance.