The following information was taken from an unpublished article by Rami Nagel, sent to me by Food Chemist Dr. Russ Bianchi.
In the quest to find a substitute for sugar that is natural and healthy, agave nectar and agave syrup have become extremely popular. These sweeteners are advertised as "diabetic friendly," raw, and a "100% natural sweetener." Yet they are none of these.
Agave nectar is in reality not a natural sweetener but a highly refined form of fructose, more concentrated than the high fructose corn syrup used in sodas!
Many people think that fructose is healthy because it comes from fruit and is labeled as having a low glycemic index. Actually this is a myth. The sugar that comes from fruit is called levulose and there are big differences between levulose and fructose which is highly processed and chemically altered.