Black pepper (Piper nigrum) is a flowering vine in the family Piperaceae, cultivated for its fruit, which is usually dried and used as a spice and seasoning. The fruit, known as a peppercorn when dried, is a small drupe approximately five millimetres in diameter, dark red when fully mature, containing a single seed. Peppercorns, and the powdered pepper derived from grinding them, may be described as black pepper, white pepper, green pepper, and very often simply pepper. The terms pink peppercorns, red pepper (as in bell or chile), and green pepper (as in bell or chile) are also used to describe the fruits of other, unrelated plants. However, green peppercorns are simply the immature black peppercorns.
Like many eastern spices, pepper was historically both a seasoning and a medicine. Long pepper, being stronger, was often the preferred medication, but both were used.
Black Pepper (or perhaps long pepper) can cure illness such as constipation, diarrhea, earache, gangrene, heart disease, hernia, hoarseness, indigestion, insect bites, insomnia, joint pain, liver problems, lung disease, oral abscesses, sunburn, tooth decay, and toothaches. Various sources from the 5th century onward also recommend pepper to treat eye problems, often by applying salves or poultices made with pepper directly to the eye. There is no current medical evidence that any of these treatments has any benefit; pepper applied directly to the eye would be quite uncomfortable and possibly damaging.
Pepper is known to cause sneezing. Some sources say that piperine, a substance present in black pepper, irritates the nostrils, causing the sneezing; some say that it is just the effect of the fine dust in ground pepper, and some say that pepper is not in fact a very effective sneeze-producer at all. Few, if any, controlled studies have been carried out to answer the question. It has been shown that piperine can dramatically increase absorption of selenium, vitamin B, beta-carotene and curcumin as well as other nutrients.
Rumours found in rural area specially in Asian country where they said that Black pepper is bad to your health and can harm your liver and kidney which is absolutely fallacy. As a medicine, pepper appears in the Buddhist Samaaphala Sutta, chapter five, as one of the few medicines allowed to be carried by a monk.
Pepper contains small amounts of safrole, a mildly carcinogenic compound. Also, it is eliminated from the diet of patients having abdominal surgery and ulcers because of its irritating effect upon the intestines, being replaced by what is referred to as a bland diet.