We all have a craving for a sweet taste and often satisfy this craving with
sugar or fat-filled foods. Even "natural" sugar substitutes, such as honey,
maple syrup or molasses, can be unhealthy if over-consumed since they can
markedly elevate blood sugar levels. Hence, stevia can be advantageous to
practically everyone whose diet contains sweeteners.
Although stevia can be helpful to anyone, there are certain groups who are
more likely to benefit from its remarkable sweetening potential. These
include diabetics, those interested in decreasing caloric intake, and
A Godsend to Diabetics
The availability of artificial sweeteners has been of enormous benefit to
diabetics. However, there's always been a concern that over consumption of
these synthetic sweeteners may cause some unknown harm to the body. Could
stevia substitution be a good alternative in diabetics? We believe so. Stevia
leaves have been used as herbal teas by diabetic patients in Asian countries.
No side effects have been observed in these patients after many years of
continued consumption (Suttajit, 1993). Furthermore, studies have shown that
stevia extract can actually improve blood sugar levels (Alvarez, 1981, Curi,
In 1986, Brazilian researchers from the Universities of Maringa and Sao
Paolo evaluated the role of stevia in blood sugar (Curi, 1986). Sixteen
healthy volunteers were given extracts of 5 grams of stevia leaves every six
hours for three days. The extracts from the leaves were prepared by immersing
them in boiling water for 20 minutes. A glucose tolerance test (GTT) was
performed before and after the administration of the extract and the results
were compared to another group who did not receive the stevia extracts.
During a GTT, patients are given a glass of water with glucose and their
blood sugar levels are evaluated over the next few hours. Those who have a
predisposition to diabetes will have a marked rise in blood sugar levels.
The volunteers on stevia were found to have significantly lower blood sugar
levels after ingestion of stevia. This is a positive indication that stevia
can potentially be beneficial to diabetics who substitute stevia in order to
decrease their sugar consumption. Even if stevia by itself is not able to
lower blood sugar levels, just the fact that a diabetic would consume less
sugar is of significant importance in maintaining better blood sugar control.
If you're diabetic, chances are you consume a large amount of artificial
sweeteners and you may be concerned about switching to stevia since long-term
human studies have not been done with this herb. You may also be accustomed
in your use of these artificial sweeteners and would not be willing to
completely stop them. One option is to gradually use less of them while
substituting stevia. For instance, you can initially use stevia in some of
your drinks, like coffee or tea. After a few weeks, if your comfort level
with stevia increases, you can gradually use more of the herbal extract. Over
the next few weeks and months you can either switch completely to stevia, or
you can continue using it in combination with artificial sweeteners. With
time more research will become available on the safety of stevia and
artificial sweeteners. Based on the results of these studies, you can
determine which ones to continue using in a larger amount.
It's also quite possible that artificial sweeteners may be safe in low
amounts, but problems could arise when they are used in excessive quantities.
By partially or mostly substituting stevia, you can reduce any potential
It would seem quite obvious that substituting a no-calorie sweetener to sugar
would help reduce caloric intake and thus contribute to weight loss. And such
is the case with aspartame. Researchers at the Center for the Study of
Nutrition Medicine, Beth Israel Deaconess Medical Center, at Harvard Medical
School in Boston, Massachusetts, studied the influence of aspartame on
obesity (Blackburn, 1997). One hundred sixty-three women were randomly
assigned to consume or to abstain from aspartame-sweetened foods and
beverages for 16 weeks. Both groups were also actively involved in a
weight-control program using a variety of modalities. At the end of the 16
weeks, both the group on aspartame and the group without the synthetic
sweetener lost 10 kilograms. During the maintenance phase that lasted the
next two years, women assigned to the aspartame-treatment group gained back
4.5 kilogram, whereas those not on aspartame gained back 9.4 kilograms,
practically all the weight they had previously lost. The researchers state,
"These data suggest that participation in a multidisciplinary weight-control
program that includes aspartame may facilitate the long-term maintenance of
reduced body weight."
Unfortunately, no formal studies have been done evaluating stevia
substitution in relation to weight loss. We would suspect, though, that the
results would be similar to the aspartame study discussed above. If you are
the type of person who adds sugar to your morning coffee or tea, or to iced
tea, lemonade, and a variety of desserts and baked goods, then, over time,
the elimination of these refined sugar calories could make a significant
Sweet Teeth with No Cavities
Even a five-year old child knows that sugar causes tooth cavities. There are
certain bacteria in our mouths, particularly streptococci mutans, that
ferment various sugars to produce acids. These in turn eat through the enamel
of the tooth causing pockets or cavities. For a long time, scientists have
searched to find alternative sweeteners that are not fermentable by bacteria
and hence do not cause cavities. Artificial sweeteners have been helpful in
Does ingesting stevia lead to tooth cavities? A study done on rats has
not shown this to be case. Stevioside and rebaudioside A, the two primary
sweet constituents of the stevia plant, were tested in a group of sixty rat
pups (Das, 1992) in the following way:
Group 1 was fed sucrose (table sugar), at 30 percent of their diet
Group 2 was given 0.5 percent of their diet in stevioside
Group 3 got 0.5 percent of their diet in rebaudioside A
Group 4 ingested no sugars.
After 5 weeks, all four groups had their teeth evaluated. There were no
differences in food and water intake and weight gain between the four groups.
However, the first group had significantly more cavities than the rest of the
groups. Groups 2, 3, and 4 were equivalent.
The researchers state, "It was concluded that neither stevioside nor
rebaudioside A is cariogenic [cavity causing] under the conditions of this
study." It appears that the chemicals within the stevia plant that impart its
sweetness are not fermentable, and thus do not cause tooth cavities.
Use in Children
Candies, sodas, ice cream, pies, cakes... it's disturbing how many sweet
products are ingested by children on a daily basis. All that sugar can lead
to tooth cavities and obesity. We believe that partially substituting with
stevia can help children satisfy their sweet tooth while decreasing the risks
from excessive sugar intake.
If you're a parent, you can take advantage of the many recipes provided
in the second half of this book to provide your children with tasty sweets
that will satisfy their sweet teeth but not cause damage to the teeth.
Obesity in children is a growing problem in this country and any method we
have of helping children reduce their caloric intake will be greatly
We also are concerned with children overconsuming excessive amounts of
artificial sweeteners. The potential, long-term health consequences of
saccharin and aspartame ingestion are currently not fully known, but they do need to be kept in mind. Eliminating all artificial sweeteners will be a frustrating enterprise since they are extremely prevalent. However, by
partially substituting stevia in homemade desserts, you can significantly
reduce your children's exposure to these artificial chemicals.
Hopefully, with time, stevia can be added to a variety of sodas, candies,
gums, and other foods in the US, just like it currently is in Japan and other countries.
In 1991, Dr. M.S. Melis, from the Department of Biology at the University of Sao Paulo in Brazil, gave a one-time high dose injection of stevioside to rats and found that it caused a reduction in blood pressure as well as an increased elimination of sodium (Melis, 1991). A slight diuretic effect also occurred. The effect was additive when stevia was combined with verapamil (a medicine used to lower blood pressure in humans who have high blood pressure).
Dr. Melis repeated a similar study in 1995. This time, he administered
extracts of stevia to rats for 20, 40, and 60 days. After 20 days, there were no changes in the stevia-treated rats compared to the control group (the ones that didn't receive the extracts). However, after 40 or 60 days of administering the extract, there was a lowering of blood pressure, a diuretic effect was noted along with loss of sodium. The amount of blood going to the kidneys was increased.
When normal human volunteers between the ages of 20 to 40 years were
given a tea prepared with stevia leaves, a lowering of blood pressure
occurred (Boeck, 1981). This study was done in Brazil. Certainly more human
studies are needed before we can come to any conclusions regarding the full
effect of normal daily ingestion of stevioside on blood pressure.
Update May 2000 by Ray Sahelian, MD
How does stevia’s sweetness compare to other artificial sweeteners? Does it
even come close to their potency? A new study done at the Department of Food
and Nutrition, FCF-UNESP in Araraquara, Brazil, compared the relative
sweetness of stevia to that of aspartame, a cyclamate/saccharin combination,
and a 10 percent sucrose concentration. The results were interesting. An
equivalent dose of stevia, aspartame, the cyclamate/saccharin combination and
a 10 percent sucrose concentration all had practically the same potency!
Cardello HM, Da Silva MA, Damasio MH. Measurement of the relative sweetness
of stevia extract, aspartame and cyclamate/saccharin blend as compared to
sucrose at different concentrations. Plant Foods Hum Nutr 1999;54(2):119-30.