I've been avoiding researching and writing about agave nectar.
Why? Well, one reason is because it seems increasingly difficult to find solid, unbiased research.
Following is some information I've gathered about agave nectar with sources included. If you have verifiable information about this sweetener, please forward it to me. Perhaps this will be an on-going blog-community effort.
WHAT IT IS: Agave nectar (also called agave syrup) is a sweetener commercially produced in Mexico from several species of agave, including the Blue Agave (Agave tequilana), Salmiana Agave (Agave salmiana), Green Agave, Grey Agave, Thorny Agave, and Rainbow Agave.
Agave nectar consists primarily of fructose and glucose. One source gives 92% fructose and 8% glucose; another gives 56% fructose and 20% glucose. These differences presumably reflect variation from one vendor of agave nectar to another. Due to its fructose content and the fact that the glycemic index only measures glucose levels, agave nectar is notable in that its glycemic index and glycemic load are lower than many other natural sweeteners on the market.1
HOW IT IS PRODUCED: To produce agave nectar, juice is expressed from the core of the agave, called the piña. The juice is filtered, then heated, to hydrolyze carbohydrates into sugars. The main carbohydrate is a complex form of fructose called inulin or fructosan. The filtered, hydrolyzed juice is concentrated to a syrup-like liquid a little thinner than honey and ranges in color from light to dark depending on the degree of processing. The syrup naturally contains quantities of iron, calcium, potassium and magnesium, which contribute to the resulting color. 2
GLYCEMIC INDEX/LOAD: The glycemic index categorizes agave nectar between 11-19, and the glycemic load between 1-2. 3
DR. WEIL ON AGAVE NECTAR: Agave nectar is a natural sweetener that ranks relatively low on the glycemic load scale. It is sold in health food stores and online and has been growing in popularity in recent years. Although it provides as many calories as sucrose (table sugar), it is sweeter, so you can use less of it - say one-quarter of a cup to substitute for one cup of sugar in recipes. I like the taste of agave nectar and have started using it in my kitchen, as well as trying products that contain it.
A 2006 review of the scientific literature on agave published in HerbClip™, on the Web site of the American Botanical Council, concluded that it is safe to use agave in the amounts usually found in foods and beverages, but the reviewers cautioned that pregnant women should avoid it because some species (more than 200 have been identified) contain anordin and dinordin, steroids with contraceptive effects that could lead to miscarriage. I think this is a very low risk. I am more concerned about the sustainability of agave as a food source, because demand may soon exceed supply.4
Recipe with agave: PCRM.org is a wonderful organization committed to nutrition, education and responsible medicine. President of PCRM and medical doctor, Dr. Neal Barnard, published Program for Reversing Diabetes that includes a recipe containing agave nectar. 5
Metabolizing Fructose: It seems like a recurring health-related issue with agave is its high levels of fructose. The American Journal of Clinical Nutrition states: "Most of the metabolic effects of fructose are due to its rapid utilization by the liver and it by-passing the phosphofructokinase regulatory step in glycolysis, leading to far reaching consequences to carbohydrate and lipid metabolism." Click on the link to AJCN below for more information. 6