One of the most popular new fad sweeteners on the market is agave syrup. It's popularity as a healthy sweetener has boomed over the past ten years, especially with vegetarians and raw foodists who look for the "raw blue agave".
Whenever any industry runs with something and starts putting it in everything, red flags are raised for me. I started researching agave syrup several years ago and as of three years ago have come to my own conclusion that it is not a safe sweetener for regular consumption. Here's why:
Agave syrup is not made from juicing the leaves of the agave plant as the imagery in the name "agave syrup" may infer. It is actually created through processing the incredibly starchy root bulb. After processing through high heat or enzymes or the mold aspergillis, a highly complex process yields the extremely high fructose syrup of "agave". In fact, the fructose content of agave syrup resembles or is even greater than our recently discredited relative high fructose corn syrup.
For anyone who doesn't already know, high fructose corn syrup is one of the most harmful sweeteners that is commonly added to almost every packaged food. A lot of people think fructose is in fruit, so it must be good for you. However, they forget that in fruit fructose is never on its own. It is always bound to other sugars, pectin, and fibers in a complex with vitamins, amino acids and minerals. Fructose consumed in fruit has an entirely different molecular structure and is digested in the gut by enzymes and beneficial flora. The fructose found in agave syrup and high fructose corn syrup is not, it mainly has to be dealt with by, and is a major burden for, the liver.
"But it's low on the glycemic index!" praise many people. The glycemic index measures glucose, not fructose. Glucose directly affects blood sugars by stimulating the release of insulin and therefor, leptin- the hormone that regulates appetite. Herbalist Karen Vaughan tells us, "as explained by Russ Bianchi, Managing Director and CEO of Adept Solutions, Inc.,.... the fructose in HFCS [and agave syrup] is therefore not recognized in the human Krebs cycle for primary conversion to blood glucose in any significant quantity, and therefore cannot be used for energy utilization. Instead, these refined fructose sweeteners are primarily converted into triglycerides and adipose tissue (body fat)". The Weston Price Foundation also finds that "fructose enters the cells through the action of something called Glut-5 transporter, which does not depend on insulin. This transporter is absent from pancreatic B-cells and the brain, which indicates limited entry of fructose into these tissues. Glucose provides “satiety” signals to the brain, which fructose cannot provide because it is not transported into the brain". What's happening is this free form fructose from agave inhibits leptin so you don't feel full, eat more, and the agave you do consume is mainly being stored as fat, not used for energy.
So to conclude, agave may be low on the glycemic index, but that doesn't make it a healthy sweetener. Herbalist Karen Vaughan shows that "[f]ructose doesn't raise blood sugar nor does it trigger insulin, but it increases fat storage, raises triglycerides and interferes with leptin which regulates appetite, so that you never feel full." Fructose interferes with normal, important use of key minerals by the heart and causes liver insulin resistance.
For more detailed and technical information about why agave is basically high fructose corn syrup and why it is best to avoid it, see these resources: