Type 2 diabetes patients tested
Pharmacy researchers from Malaysia’s University MARA have confirmed human clinical research illustrating that Stevia increases glucose control. In that study from Denmark’s Aarhus University, 12 type 2 diabetic patients were given stevioside isolated from the Stevia rebaudiana plant or a placebo.
The one gram of stevioside resulted in an 18% reduction in the glucose response curve area. Furthermore, their insulinogenic index – measuring insunlin beta cell function and insulin sensitivity – increased by an average of 40% as compared to the control patients.
The researchers stated:
“In conclusion, stevioside reduces postprandial blood glucose levels in type 2 diabetic patients, indicating beneficial effects on the glucose metabolism. Stevioside may be advantageous in the treatment of type 2 diabetes.”
The new Malaysian study confirms some of the mechanisms involved in this result. The researchers tested human adipose (fat) cells that were treated to become insulin resistant. The researchers utilized TNF-alpha to produce the insulin resistance – a mechanism that mirrors insulin resistance mechanisms in the body – producing a diabetic condition.
Cells tested and compared
The insulin-resistant cells were then treated with stevioside, and these were compared with cells that were treated with the antidiabetic drug rosiglitazone maleate – branded as Avandia.
The two test groups were also treated with or without added insulin – which tested the treatments in an environment mirroring metabolism.
The researchers found that the cells treated with stevioside absorbed glucose at a rate more than twice the rate of the antidiabetic drug rosiglitazone maleate in the insulin environment, and 1.7 times in the non-insulin environment.
Furthermore, the stevioside increased glucose absorption by the fat cells in a dose-dependent manner. This is the gold-standard for determining whether a biochemical is truly enhancing the end result or whether there are other participants.
This result – stevioside outperforming the antidiabetic drug rosiglitazone maleate by more than double – confirms the clinical study discussed above, as well as other studies that have shown stevia’s antidiabetic treatment abilities.
This is not the only benefit of stevia. Other studies have shown that stevia supplies antioxidant activity. Spanish researchers found stevia extracts contained flavonoids like catechin and phenols like gallic acid. Stevia also contains some 11 amino acids.
What about commercial Stevia sweeteners?
As to whether the stevia sweeteners contained in new drinks maintain these benefits, the jury is still out. Literally.
Many of the commercial stevia sweeteners on the market utilize steviol glycosides that are extracted from the Stevia leaf utilizing extraction methods, including calcium hydroxide and aluminum sulfate, as well as adding hexane or chloroform during the drying process. Some are also treated by erythritol made from a yeast fermentation process using GMO corn.
The labeling of Stevia sweeteners as natural, in fact, was contested in a class action lawsuit filed last year by Kevin Anderson. The suit challenged that the extraction process should bar the stevia sweeteners (such as Truvia) supplied by ConAgra, Kraft and PepsiCo from claiming “natural” on their labels.
Cargill settled recently on its lawsuit challenge – setting up a fund to pay any consumers damaged by the “natural” claim.
Still, if offered nothing but a choice between high-fructose corn syrup or one of these commercial Stevia sweeteners, I’d chose the Stevia any day of the week.
This isn’t to say that all Stevia sweeteners are not natural. There are several Stevia products found in health food stores that utilize extraction methods without additions such as those mentioned above.
REFERENCES:
Nabilatul Hani Mohd-Radzman, Wan Iryani Wan Ismail, Siti Safura Jaapar, Zainah Adam, and Aishah Adam, “Stevioside from Stevia rebaudiana Bertoni Increases Insulin Sensitivity in 3T3-L1 Adipocytes,” Evidence-Based Complementary and Alternative Medicine, vol. 2013, Article ID 938081, 8 pages, 2013. doi:10.1155/2013/938081
Gregersen S, Jeppesen PB, Holst JJ, Hermansen K. Antihyperglycemic effects of stevioside in type 2 diabetic subjects. Metabolism. 2004 Jan;53(1):73-6.
Periche A, Koutsidis G, Escriche I. Composition of Antioxidants and Amino Acids in Stevia Leaf Infusions. Plant Foods Hum Nutr. 2013 Dec 1.
Watson E. Steviol glycosides are not all-natural says new class action lawsuit. Food Navigator. Acc. Dec. 13, 2013.
Weingarten H. Lawsuit Leads to Settlement: Stevia May Be Natural, But Truvia is Not. Acc. Dec. 13, 2013