To date, research has been done entirely in the lab, in test tubes (in vitro) or with non-diabetic rats, but not yet on humans. It is therefore very difficult, and in some cases impossible, to determine whether the same effects would obtain for humans or the amount of maple syrup that would need to be consumed to see any potential health benefits.
Maple syrup naturally contains minerals and other elements with antioxidant properties. According to preliminary research, antioxidants, whether from maple trees or other sources, would be beneficial for people with diabetes because they reduce inflammation of the blood vessels, but their real short- or long-term effect remains to be proven.
A low glycemic index
Researchers have also compared the glycemic index of different types of carbohydrates[a1] . They have determined that eating maple syrup causes a lower rise in blood glucose (sugar) levels than white sugar, corn syrup or brown-rice syrup, and they have given maple syrup a low glycemic index[a2] , similar to honey, molasses and agave syrup.
Other potential benefits of maple syrup
Some specialists are interested in the plant hormones in maple sap, particularly abscisic and phaseic acids. These hormones normally stimulate the growth of plants and are found in high concentrations in maple sap.
Studies on laboratory-grown muscle cells show that these plant hormones promote glucose uptake by the muscles, without any additional insulin secretion by the pancreatic beta cells. This greater glucose tolerance by the muscles could contribute to better blood glucose control and protect the insulin-production function of the pancreas.
Maple syrup remains first and foremost a concentrated source of carbohydrates. One tablespoon (15 ml) of maple syrup contains about 15 g of carbohydrates. This is as many carbohydrates and calories as an equivalent amount of white sugar.
For the moment, people with diabetes should keep in mind that even if maple syrup contains some potentially promising elements, it remains a food that should only be eaten once in a while and in limited quantities, just like other sources of concentrated carbohydrates.
Maple syrup can be used to replace other sugars that a person with diabetes adds to food, while respecting their meal plan.