Pots of honey dating back over 5000 years have been found in tombs in ancient Egypt and have been determined to be just as safe and edible as honey bought at the local grocery store. Because of its unique properties, being high in sugars which are naturally hygroscopic, very few bacteria and microorganisms can live in the resulting low-moisture environment. Further, honey has a high acidity with a pH between 3.26-4.48 which kills off any microorganisms trying to make their home in the honey.

The primary reason honey has such a low moisture content is thanks to its makers: bees. The flapping of their wings helps the moisture in the nectar evaporate. After they gather the nectar, the way bees get it into the honeycombs is by vomiting. As gross as it sounds, the chemical content of bees' stomachs contains the enzyme glucose oxidase which remains in the nectar after it is regurgitated. The enzymes mix with the nectar to create gluconic acid and hydrogen peroxide which is also excellent at preventing bacterial growth.

While honey does not spoil, it can crystalize over time. Crystalized honey is not spoiled and heating it slightly will dissolve the crystals and return the honey it its natural liquid state. Honey most quickly crystalizes at temperatures between 50-59 degrees F so avoid refrigerating to help prevent crystallizations.

Infants under a year old, whose gastro-intestinal tracts aren't fully developed, should never be given honey.

More Info: io9.gizmodo.com