Elevated cortisol is a huge problem for many men and will destroy everything you hold dear as a male. In fact, it is actually astonishing how much damage one hormone can do. Testosterone can boost your career, relationships and sex life. Cortisol will undo the same and tear you apart head to toe.
Don't believe me? Check out these 10 research-backed reasons that (elevated) cortisol and manliness just do not go together well:
1. Visceral Fat. It is no secret that visceral (stomach or belly) fat kills. It is associated with Metabolic Syndrome and many other nasty diseases that can lead you and your sex life. What many men do not realize is that cortisol actually helps push fat to the abdomen , because, among other things, visceral fat has four times the number of cortisol receptors. 
So why do men tend toward abdominal obesity? Yep - the have great "cortisol reactivity", i.e. when under stress, they have higher cortisol levels than women.  Well, and they just tend to have higher cortisol levels.  This, on average, makes them much more susceptible to inflating that "spare tire". You can read more about it in my link on Visceral Fat and Abdominal Obesity.
2. Testosterone. Several studies have found that elevated cortisol leads to lowered testosterone levels.  How does cortisol attack your testosterone? It actually does this through an enzyme that affects testosterone in the Leydig cells of the testes. See my link on Stress and Testosterone for more information.
3. Secondary Hypogonadism. Researchers have reported that in some extreme cases stress can cause secondary hypogonadism, which means clinically low testosterone resulting from failure in the signaling to the testes and not the testes themselves. This can happen from being overweight, for example, because excess body fat can turn off proper signaling from the hypothalamus.
Well, it turns out that excess cortisol can do something similar, i.e. lower GnRH output from the hypothalamus.  Of course, GnRH is what signals the pituitary from.
4. Insulin Resistance and Blood Glucose. Higher cortisol levels are associated with increased insulin resistance and elevated blood glucose levels. 
5. Memory Loss and Brain Shrinkage.. A number of studies have shown that higher-than-normal, long term cortisol levels can damage the hippocampus, the seat of memory for all humans.  Furthermore, several structures of the brain, especially the hippocampus, have been shown to actually shrink with long term cortisol exposure. 
NOTE: If you feel you have likely damaged and/or shrunk your brain matter due to excess stress/cortisol, don't panic. Researchers have found good evidence that the brain shrinkage is actually reversible (to one degree or another) for a number of high-cortisol conditions, including depression  and Cushing's . The reversibility (significant but partial) of Cushing's Syndrome brain matter loss is particularly significant considering the severity of the disease.
In addition, you can likely rebuild and increase your brain through mindfulness meditation  or the vispanna meditation.  Progressive Muscle Relaxation will certainly protect your hippocampus from damage and may help to rebuild it as well.
CAUTION: Some psychiatric illnesses (PTSD, i.e. Post-traumatic Stress Syndrome are actually characterized by low serus cortisol levels. This is probably due to overexcitation of cortisol for many years.
6. Blood Pressure. It is no secret that stress raises blood pressure and can be a significant factor in hypertension. So it should be no shock that the primary stress hormone, cortisol, has been found in multiple studies to raise blood pressure.  Of course, hypertension is a leading cause as I document in my link on High Blood Pressure and Erectile Dysfunction.
7. Arteriosclerosis. One study verified 5 and 6 but also found that, not too surprisingly, that higher morning cortisol levels were associated with accelerated arteriosclerosis, i.e. arterial plaque. 
8. Neuroticism and Depression. Higher morning cortisol levels have been associated with your odds of being neurotic  and may also play a role in developing depression. 
9. Metabolic Syndrome. Thanks to #1, many researchers believe that elevated cortisol may be the primary cause of the Metabolic Syndrome.  Visceral fat and insulin resistance go hand-in-hand, so this is no wonder. Several studies have shown that stress and Metabolic Syndrome are related giving still more evidence to this relationship. 
10. Diabetes. With the decreases in insulin sensitivity and the increases in blood glucose very often comes Type II diabetes according to the latest research as well.
11. Cholesterol. Ever feel like you're fighting a losing battle with your cholesterol levels. Well, the primary reason is likely Saturated Fat - see my page Why Saturated Fat Can Be Bad For Men According to the Latest Research - but cortisol can play a role as well and studies have shown that elevated cortisol can in turn elevate cholesterol levels as well. 
12. Erectile Dysfunction. Stress has been tied into erectile dysfucntion and itis no wonder considering that it almost always raises cortisol, which in turn raises so many cardiovascular risk factors. 
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