The prostate is a gland in men. It helps make semen, the fluid that contains sperm. The prostate surrounds the tube that carries urine away from the bladder and out of the body. A young man's prostate is about the size of a walnut. It slowly grows larger with age. If it gets too large, it can cause problems. This is very common after age 50. The older men get, the more likely they are to have prostate trouble.

Some common problems are

• Prostatitis - inflammation, usually caused by bacteria
• Enlarged prostate (BPH), or benign prostatic hyperplasia - a common problem in older men which may cause dribbling after urination or a need to go often, especially at night
• Prostate cancer - a common cancer that responds best to treatment when detected early

NIH: National Institute of Diabetes and Digestive and Kidney Diseases