Below Are Some Signs of ED:
 
During sleep, you do not attain full erections at times (when the mind and  psychological issues, if any, are less present).  Do not be alarmed though,  since a lack of nocturnal erections does not imply the opposite as men do not  have frequent wet dreams.
 
Experiencing lazy erection or one which is more rapid than would be expected  (often before or during penetration), can be a sign of a failure of the  mechanism which keeps blood held in the penis, and may signify an underlying  clinical condition, often cardiovascular in origin.
 
Other factors leading to erectile dysfunction are decreased testosterone  levels due to disease affecting the testicles or the pituitary gland.
 
Anxiety
 
As mentioned earlier, the male organ signifies masculinity and success in  most cultures.  Fear of not performing might cause one to feel emasculated.   Due to this "perfectionist" mentality; one feels tremendous pressure, thus  lacking concentration.  Perfectionists are likely to feel depressed because  they expect a certain standard in themselves and if they are unable to cope,  expect society to view him in a certain way.
 
Depression
 
We go through depression every now and then.  Long term depression,  though, makes us feel inadequate and we slump into a comfort zone where it feels  great to be depressed.
 
Lifestyle
 
Excessive smoking, drinking and drug abuse.  (Read QUIT SMOKING for more  repercussions and ways to rid the addiction.)
 
Physiology
 
- Hormonal disorders (low levels of testosterone or tumor in the pituitary   gland)
- Neurological disorders (brain and spinal cord injury, nerve disorders   such as Parkinson's and multiple sclerosis)
- Arterial disorders (reduced blood flow to the penis)
- Cavernosal disorders (Peyronie's disease)
- Surgery (surgery in the rectum, prostate, colon and even radiation   therapy may damage the nerves and blood vessels involved in erection.)
 
Resources taken from Guardian - The one you trust
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