Smoking

Nicotine constricts the arteries by up to 30%, and that results in 50% less blood flow. Of all the behaviors that can damage your health none has been as thoroughly documented as smoking. 

Not only does it promote heart disease and cancer, but when it is combined with other risk factors, its harmful effects on penis health.

Smoking is linked with impotence, non-rigid erection and sub-fertility. And because it constricts blood flow to the penis, it could affect your penis size as well.

The good news is if you quit smoking, within a period of 1-3 months, you will experience more rigid erections, and an increase in your sperm count.

Stress

Internal pressure such as lack of sleep and relaxation, working too hard, and physical exhaustion will cause stress. Stress can also be caused by external pressure such as changes in family or work environment.

Stress may cause impotence, premature or retarded ejaculation in terms of your penis health aspects. Learn to relieve stress by exercising, getting enough sleep and rest, going away for holidays to unwind, and try to solve the source which is giving you the stress.