Honey is a sweet, viscous food substance produced by bees and some related insects. Bees produce honey from the sugary secretions of plants (floral nectar) or other insects (aphid honeydew) through regurgitation, enzymatic activity, and water evaporation. Honey is stored in wax structures called honeycombs. The variety of honey produced by honey bees (the genus Apis) is the best-known, due to its worldwide commercial production and human consumption. Honey is collected from wild bee colonies, or from hives of domesticated bees, a practice known as beekeeping. Honey gets its sweetness from the monosaccharides fructose and glucose, and has about the same relative sweetness as sucrose (granulated sugar). It has attractive chemical properties for baking and a distinctive flavor when used as a sweetener. Most microorganisms do not grow in honey, so sealed honey does not spoil, even after thousands of years.Honey provides 46 calories in a serving of one tablespoon (15 ml) equivalent to 1272 kJ per 100 g. Honey is generally safe, but may have various, potentially adverse effects or interactions upon excessive consumption, existing disease conditions, or use of prescription drugs.Honey use and production have a long and varied history as an ancient activity, depicted in Valencia, Spain, by a cave painting of humans foraging for honey at least 8,000 years ago.