Juniper berries are classified in the culinary herb/spice category because they are commonly used as a flavoring for drinks and in cooking and preserving foods. it is also considered an herbal bitter and is thought to help promote digestion.
Juniper is a strong aromatic (scented) herb from an evergreen plant or tree. It grows in temperate regions of Northern Europe, Asia, and North America. The cone of the juniper is the part that is referred to as the berry. It looks like a small green berry and ends up turning a bluish-black shade in the second year of growth.
The most common culinary use of the juniper berry is as a spice used to flavor gin. It's used for its medicinal purposes as an essential oil, made by steam distillation of the crushed, dried, or fermented berries. Juniper berries are also used as a dried fruit. The oil is said to have diuretic and antiseptic properties.
Juniper berry oil is also known as a gastrointestinal irritant, which is thought to help promote the movement of food through the digestive tract. The dried fruit and oil are used to relieve an upset stomach. Note, unlike many essential oils, juniper berry essential oil is FDA approved for limited internal use.
The ancient Romans, Greeks, and Egyptians were known to have used juniper berries. In fact, the Greeks used juniper berries as an herb for purification ceremonies and to increase physical stamina (particularly for athletes), recording the use of juniper berries as a medicine long before they were said to start using the berries as a spice in foods.
The Romans also used juniper berries as a cheaply produced substitute for black pepper, which was expensive to import from India. Juniper berries have even been found in Egyptian tombs; the Egyptians used juniper as a medicinal herb and to embalm the deceased.
In Traditional Chinese Medicine (TCM) juniper berries have been used for centuries as a stimulant for the kidneys and bladder to flush out impurities and toxins. It has also been used as a general antibiotic herb to heal infections, as well as a digestive tonic for the stomach, intestines, and spleen.