Maple syrup is indigenous to North America and was first used there by native peoples. Maple trees store starches in their roots and trunk for the winter; these starches are converted into sugar, which then rises in spring as sap to be tapped and drained off.
Concentrated syrup is produced by boiling the sap to reduce water content and leave about two thirds of the total as sugar. Regulations determine the precise content, flavour and quality of maple syrup, but pure maple syrup must be 100% concentrated maple sap.
Maple syrup is mostly composed of sugars, with very little fat or protein, but also has a number of the B complex vitamins (notably riboflavin) and some rich supplies of minerals, particularly calcium, magnesium and potassium. Its glycemic index is lower than refined sugar, making sugar uptake levels in the blood slightly slower.
Recent research has identified maple syrup as the source of a polyphenol newly labelled Quebecol (after the largest global producer), which may be instrumental in fighting off invasive cells, reducing inflammation and combating oxidative stress in the immune system. There are claims that there are as many as 24 antioxidants in maple syrup, with darker syrups having more than lighter.