Obesity

Increasing intake of junk / convenience food and lack of regular, vigorous exercises have made more people becoming overweight. 

Overweight affects one's long term health, and is linked to lower sperm count, lower libido and sub-fertility. Being overweight is associated with the deposition of fatty deposits on the interior arterial walls, which restricts the blood flow to the penile tissues, thus may affect the penis size.

Alcohol

When consume in excess, alcohol acts as a toxic drug with serious short and long term consequences for your health. 

Excessive alochol is linked with non-rigid erections, impotence and subfertility. This occurs because alcohol interferes with messages between the brain's pituitary gland and the penis.