Stevia is a natural sweetener with no calories, documented health benefits, and a long history of medicinal use in South America, where the plant originates.
The dark side of refined white sugar has been common knowledge for years. As more research conclusions roll in about the way sugar consumption contributes to poor health and the development of chronic disease, the popularity of alternative sweeteners continues to grow.
Nearly a quarter of American adults and about half that many children used sugar substitutes regularly in 2012. (1)
Stevia comes from a green plant with leaves containing two different compounds, steviocide and rebaudioside A, which are a hundred times as sweet as sugar.
It’s possible to grow stevia yourself, and the leaves will contain approximately 10% steviocide. You could dry these, crush them, and mix them with an herbal tea product, for example. It might be tricky to get the right amount to suit your sweet tooth, but it would be effective.
The products you’ll find on the market are usually powders or liquids refined from the compounds occurring naturally in stevia leaves. These are obviously designed for convenient use, and have established a loyal following over the past few years.
Stevia may be the only existing calorie-free sweetener that actually has benefits.
Putting Sweet Stuff to the Test
The studies we’ll look at are based on subjects taking stevioside supplements. Concentrated versions of the substance were used in these trials, because it wouldn’t be practical to consume the amount of stevia leaves necessary to duplicate test levels of stevioside.
The first study focused on blood pressure measurements for 174 Chinese patients. A double-blind, randomized trial with placebo controls was conducted over a 2-year period, and participants took 500 milligrams of stevioside three times daily. (2)
Patients experienced significant reductions in both systolic and diastolic blood pressure. Researchers believe the stevioside may act like a class of drugs for lowering blood pressure called calcium channel blockers, which affect cell membrane function. (3)
Average drops for systolic measurements clocked in at 10 points (from 150 mmHg to 140 mmHg), while diastolic readings went down 6 points (from 95 mmHg to 89 mmHg). With the length of the study, these results may indicate good possibilities for using steviocide as a natural remedy for the condition.
Hypertension (high blood pressure) is a reliable marker for increased risk of developing heart disease, which is the leading cause of death worldwide. (4)
The group taking stevioside in this study reported improved quality of life, and also lowered their risk of developing left ventricular hypertrophy, which is an enlargement of the heart that can result from hypertension.
An animal study found that stevia decreased the amount of oxidized LDL cholesterol in the blood; if it affects humans in a similar manner, stevia could open another avenue for dropping heart disease risk factors. (5)
The sweet compounds from stevia plants also performed well in studies with patients being treated for type 2 diabetes, another modern disease of epidemic proportions.
In this clinical trial, the control group took a gram of maize starch (placebo) with meals, while the other group took a gram of stevioside. Blood sugar levels dropped by 18% in the stevioside group. (6)
Lab experiments with test tubes and animals indicate steviocide may also stimulate insulin production, which is the hormone that drives blood sugar into the cells for use as fuel. (7, 8)
Other animal studies suggest stevia may have anti-inflammatory properties; there may also be benefits in protecting against cancer and modulating the immune system. (9)
Since the results from animal studies aren’t always a good predictor for how humans will react in the same circumstances, further research will bring more information to light.
When stevia’s effects on test subjects’ blood sugar after eating a meal was compared with table sugar (sucrose) and aspartame, results noted lower blood sugar levels and insulin readings with stevia. (10)
Two recent comprehensive reviews of stevia studies indicate no ill health effects have surfaced. (11, 12) While animal studies using massive amounts of stevia led researchers to believe fertility could be affected, the circumstances aren’t likely to be duplicated in human experience. (13, 14, 15)
A Couple of Small Problems . . . .
While stevia is sweet, it also has a bitter aftertaste some people don’t care for.
As more stevia products are developed, taste has become less of an issue, but the most common way manufacturers address the problem won’t suit everyone.
Stevia extract is often combined with other substances, including maltodextrin, which is a highly processed starch derived from potatoes, corn or rice. In this application, its non-clumping qualities are valued, since it can be difficult to achieve even distribution of those tiny, super-charged granules of dried stevia. (16)
Another additive used in stevia sweeteners is inulin. This is an innocuous plant fiber that helps in the dissolving process and may be preferable to maltodextrin.
Fructooligosaccharides (FOS) are also used as an additive to stevia sweetener products. This insoluble plant fiber is known for its positive impact on friendly digestive bacteria, and may add more benefits to your choice. (17)
Stevia is sometimes combined with other sweeteners, which can also mute the bitterness. One popular brand contains stevia and xylitol, a sweetener with about half the calories of sucrose (sugar).
Since stevia doesn’t have the bulk of sucrose, substituting in recipes can be challenging, but there are now products containing stevia made especially for baking. This adjustment makes it more likely the end-product will be reasonably comparable to the original recipe calling for sugar.
If you have concerns about how stevia products are processed, research the brand you enjoy. Water extraction, along with crystallization and purification, is the most common processing method for making the leap from a green leaf to a white powder. (18)
Liquid stevia is technically a tincture made from plant leaves, so it may be more acceptable to some; it’s often suspended and preserved in alcohol, but water-based tinctures are also available. (19)
Read labels for products containing stevia so you’ll know exactly what you’re buying.
Recap
A natural sweetener with positive effects on blood sugar measurements as well as other health markers is good news for anyone with a sweet tooth.
Summary: If you’re looking for an alternative to white sugar, stevia is one of the best bets you’ll find in today’s health food marketplace.
References:
- http://www.livescience.com/39601-stevia-facts-safety.html
- http://www.ncbi.nlm.nih.gov/pubmed/14693305
- http://www.ncbi.nlm.nih.gov/pubmed/1342842
- http://www.who.int/mediacentre/factsheets/fs310/en/
- http://www.ncbi.nlm.nih.gov/pubmed/20010904
- http://www.sciencedirect.com/science/article/pii/S0026049503003871
- http://www.ncbi.nlm.nih.gov/pubmed/10690946
- http://www.ncbi.nlm.nih.gov/pubmed/16278783
- http://www.sciencedirect.com/science/article/pii/S0163725808001927
- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2900484/
- http://www.ncbi.nlm.nih.gov/pubmed/19961353
- http://www.ncbi.nlm.nih.gov/pubmed/20370653
- http://www.ncbi.nlm.nih.gov/pubmed/10619379
- http://www.sciencedirect.com/science/article/pii/037887419501271E
- http://www.ncbi.nlm.nih.gov/pubmed/2785472
- http://www.healthline.com/health/food-nutrition/is-maltodextrin-bad-for-me#2
- http://www.ncbi.nlm.nih.gov/pubmed/20119826
- http://www.livestrong.com/article/54052-stevia-processed/
- http://renegadehealth.com/blog/2011/08/20/whats-so-bad-about-white-stevia-powder