NOW e-newsletter
December 5, 2003
The Sweet Stevia Science
By Allison Tannis, BSc, MSc
Nutritionist, Puresource Natural Products
With the current epidemic of obesity there is a need to find alternatives to white
sugar. Stevia is a naturally sweet, all-natural herb that has a number of reasons why it is
the healthier alternative. Scientific studies are limited on stevia; however, it’s important
to investigate them as they highlight some great features of stevia that makes it an ideal
choice for many diseases such as diabetes, hypertension and cancer.
Stevia is from the leaves of Stevia rebaudiana. It’s a sweet substance that can be
easy used in place of sugar (i.e. ¼ to ½ tsp of stevia for 1 cup of sugar), but it does not
cause the same detrimental effects as sugar in the body. Therefore, diabetics may find
stevia to be beneficial as it offers a sweet taste, but does not result in a sharp increase in
blood sugar. In fact, science suggests that stevia may stimulate insulin production from
the beta-cells of the pancreas, and appears to increase glucose tolerance (i.e. antihyperglycemic effects). Therefore, stevia is an obvious choice for diabetics for both its
great taste, and its healthy benefits.
People who suffer from high blood pressure may also benefit from the use of
stevia. A number of studies have noted stevia’s ability to reduce hypertension. However,
the most convincing evidence comes from Chan et al. 2000. This multi-centered, double
blind, placebo controlled human trial was on hypertensive men. They received about 750
mg of stevia each day for a month. The results indicated that stevia is an antihypertensive and is well tolerated in humans. Therefore, stevia may reduce hypertension.
Some studies suggest that stevia may also have anti-cancer, anti-microbial and
anti-viral properties. These aspects of stevia are not yet strongly supported by scientific
literature, which is to be expected as the first study noting these properties was reported
just six years ago.
The safety of stevia has always been a debate. One study noted that in an Ames
test there was some toxicity seen; however, this does not represent the effect of stevia in
human metabolism. As some studies suggest that it may have negative aspects, others
have found it to be safe. More importantly, stevia has been used extensively in North
America for 20 years without one reported overdose, or toxicity, nor have the human
trials that have supplemented with stevia. The information to date indicates that stevia
appears to be safe.
Stevia is known as a natural sweetener. However, science suggests that it needs to
be considered as a beneficial natural product for diabetics, patients with high blood
pressure and perhaps as an anti-cancer and anti-microbial. Stay tuned to research in
coming years as the science may soon unveil the true health potential of stevia.
References:
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