Most men in mid-life and older experience some kind erectile dysfunction (ED).
Low testosterone can cause erectile dysfunction. However, diseases of the nerves and blood vessels can also affect the penis and cause erectile dysfunction.
As men age it is normal for them to have less interest in sex. However, it is abnormal for a man to have absolutely no interest in sex. This could be
caused by significantly low levels of testosterone.
Men with less sex drive, erectile dysfunction, reduced sperm count, decrease in muscle size or other signs of low testosterone should have a blood test to find out their testosterone level.
Next: — What to ask your doctor and what you should know during that interview.
Dr. Gudmundur Björnsson is an icelandic physician, a specialist in medical rehabilitation, a certified independent medical examineer (CIME) and an MBA. He now runs his own company as a medical advisor mostly in insurance medicine. He has previously been a head of a rehabilitation clinic and president IMA. 
