Research has proved that around 80% of the cases of erectile dysfunction are due to the physical factors.
Three factors are common to behind ED ( erectile dysfunction) problems.

Physical Factors
Psychogenic Factors
Lifestyle Factors

Physical Factors -
Vascular Diseases
Diabetes
Kidney Disease
Neurological Disease
Prostate Cancer

Psychogenic Factors -
Stress
Anxiety
Guilt
Depression x
Low Self Esteem
Indifference

Lifestyle Factors -
Alcohol
Smoking
Overweight
Sedentary lifestyle
Drug Abuse