Although men and women experience similar levels of stress, the lasting consequences of stress on each sex is remarkably different. Besides the health problems that can be caused by stress, it can have particularly severe effects on a man’s physiology. In women, stress brings about a tend-and-befriend reaction. In men, it causes aggression and a fight-or-flight response.

Christy Matta, MA, writer of “The Stress Response,” says, “The fight-or-flight mode switches the body into self-preservation mode. This means meeting urgent needs, fueling the muscles and ignoring everything else, including long-term needs.”

She goes on to say, “The immune and reproductive systems shut down and testosterone isn’t being released.” To kick off National Men’s Health Week, here are some of the ways that stress can affect you.

1. Reduced Visual Appeal

Testosterone, the predominant sex hormone in men, is closely linked to strong immunity and a handsome face. One study showed that women found men with higher testosterone levels, low cortisol and strong immunity the most desirable. On the other hand, men with flagging testosterone and high cortisol were less desirable.

2. Heart Disease

It’s no secret that chronic stress is a major factor in the development of heart disease. Furthermore, scientists believe that stress may have a genetic component. A study from Henry Ford Hospital showed that men with heart disease in their families tended to develop the disease over a decade sooner than their history-free counterparts.

Those with a family history also showed more stress symptoms like impatience, aggression and worry, which suggests that stress could be inherited.

3. Sperm Damage and Child Development

A new animal study shows that long periods of stress can cause sperm to mutate, which can have a significant impact on a man’s future children. How long ago the stress happened doesn’t matter, either. According to the study, this can alter a child’s ability to deal with stress.

4. Prostate Cancer

Studies performed on mice have shown that stress accelerates the growth of prostate cancer. This means that patients could reap benefits from de-stressing methods. The study, which came from the University of California, managing stress has promising results in men with the disease.

5. ED and Treatments for ED

Between ten and 20 percent of erectile dysfunction cases are the result of mental health issues such as anxiety, depression and chronic stress. Stress shuts down the parasympathetic nervous system, which is necessary for sexual arousal.

Instead, your sympathetic nervous system is running the show, which controls you body’s fight-or-flight response. Treatments for ED can help in the short-term, but controlling stress regularly is a better option.

6. Sperm Count

A study out of Italy has showed that stress can play an significant role in your ability to become a father. The study found that stressed-out men has smaller ejaculations and fewer sperm than those who were not. The researchers also found that stress caused sperm to be deformed and hindered their movement.

7. Social Isolation

There is a long-held stereotype of “strong and silent” being a measure of manliness. However, this is the classic image of someone reacting to excessive stress. A study in 2010 found that stressed men showed less neurological activity in the parts of the brain that are involved in sympathy and understanding people’s emotions.

Under acute stress, the participants displayed less reaction to face expressions, particularly of anger or fear. Women, on the other hand, showed increased activity in those centers of the brain.

Mara Mather, director of the University of Southern California’s Emotion and Cognition Lab, said, “This is the first real evidence that gender differences in the effects of stress on social interaction can affect even one of the most basic functions: determining and reacting to others’ facial expressions. Men under stress are more likely to withdraw socially, while women seek out social support.”