Stevia: A Sweetener Shrouded in Mystery and Debate

Over the past several weeks, we’ve taken a closer look at various nutritive, or caloric, sweeteners, including high-fructose corn syrup. Thank you all for your comments, questions, and suggestions. The use of sweeteners is obviously an important, and often emotionally charged, topic.


This week, I thought I’d write about stevia, a sweetener that has grown more popular with many people who are uncomfortable with using artificial sweeteners, such as aspartame and sucralose.

Stevia is an herb that belongs to the sunflower family (Asteraceae). It’s grown primarily in Central and South America and is sometimes called sweet leaf or sugar leaf. For many centuries, people living in Paraguay and Brazil have used stevia to sweeten a drink called yerba mate.

In the early 1930s, scientists isolated the ingredients, stevioside and rebaudioside, that give stevia its sweetness. These ingredients, collectively known as glycosides, are about 300 times sweeter than sucrose, although they are calorie-free and carbohydrate-free (meaning they don’t affect blood glucose levels). Stevia users describe stevia as tasting a bit like licorice.

Japan has been manufacturing stevia since the 1970s and happens to be the largest consumer of stevia compared to other countries. Stevia is also used in other Asian countries as well as in Central and South America. Interestingly, stevia has yet to be approved for use as a sweetener by the U.S. Food and Drug Administration (FDA), by Canada, or by the European Union. It is, however, available as a dietary supplement. Why?

Studies done several years ago hinted that stevia may be harmful in several ways. First, large amounts of stevia given to both male and female rodents affected their fertility and led to fewer and smaller-sized offspring. Second, in test tubes, a compound in stevia can become mutagenic; it’s not known if this could translate into cancer in humans. And third, large amounts of stevia given to animals can interfere with carbohydrate absorption. More recently, another study found that stevioside, when given to rats, caused lesions in the liver, brain, and spleen, thus supporting an earlier study that proposed that stevia might be potentially mutagenic.

On the flip side, a study published this past March showed that, in people with Type 1 and Type 2 diabetes with either normal or high blood pressure, stevia didn’t adversely affect blood glucose levels, HbA1c, or blood pressure. I’ll note that this study was conducted at the National University Asunción in Paraguay, a country that happens to grow stevia. However, to be fair, a review study published in 2003 by the Laboratory of Plant Physiology at Catholic University of Leuven in Belgium concluded that stevioside is safe to use as a sweetener. And still another study points to stevia as being a source of natural antioxidants.

So, what is one to do? Is stevia safe or not? There are plenty of Web sites on the Internet that rave about stevia (and a few that warn us of the dangers). You’ll also find recipes and even some food products that contain stevia (although I’m not sure how they’ve managed to slip by the FDA). You’ll find stevia sold as a supplement in the aisles of your neighborhood whole foods/natural foods store, and you can purchase stevia over the Internet as well.

Until we learn more about stevia, it’s probably safe to use in small amounts—say, to sweeten your tea or coffee. The FDA’s concern is that if stevia is used to sweeten soft drinks and food products, intake within a large population will greatly increase, and the health consequences just aren’t known. As the saying goes, “buyer beware.”

What are your thoughts on using stevia?

Learn more about the health and medical experts who who provide you with the cutting-edge resources, tools, news, and more on Diabetes Self-Management.
About Our Experts >>

  • tmana

    I occasionally use stevia. The large container I have has a consistency more like confectioner’s sugar and a note to use 1/3 as much as I would normally use sugar. I pretty much have to use it 1 for 1, it’s lumpy, and it has a very distinct bitter taste.
    I also have stevia packets, which are microgranulated. They work a bit better, but they’re still not my go-to. After everything, I’m most confident with small amounts of real sugar, real honey, real maple syrup, Splenda Baking Blend when I need to cut the sugar in baked goods, and sodium saccharine (Sweet-n-Low) for sugar-free non-nutritive with the least change in taste (for me).
    OTOH, I grew up on saccharine…

  • SweetLucee

    I am a true believer in Stevia. I have researched it to an extreme extent and would like to share some of my findings. Zero Carbs, Zero Glycemic Index – Zero Calories – Zero Chemicals.
    The reports of rats, hamsters and other rodents having ill effects was taken completely out of context. Imagine taking close to your body weight of anything! You might have ill effects. The fact is, that’s never going to happen. Stevia is close to 300 times sweeter than sugar. Obviously, you aren’t going to need much.
    Stevia is by far the safest and smartest way to take sugar out of your diet and still get sweetness. It’s safe for chidren and/or babies. It wont harm their teeth! Imagine that. They’ll love it & think that they’re having a treat.
    I primarily use the liquid flavors to sweeten water. It encourages me to drink more water. My favorite flavors are Root Beer, Vanilla Creme, Chocolate Raspberry (that one is wonderful in coffee) Valencia Orange, and English Toffee. You can also use these flavors in ice cube trays, shaved ice, or to sweeten bland tasting food.
    Stevia is also available in packets, and shaker bottles.
    My biggest recommendation is to make sure that when you look for it, buy the Sweet Leaf brand. There are a couple of brands out there that aren’t so pure. So, that’s my story and I’m stickin to it.
    Sweet Leaf Stevia can be found by just Googling, or Whole Food Markets and Sprouts usually carry it. The packets can be found in many grocery stores.
    Be sweet in a healty way. Try it, and you’ll love it. Really!

  • Mariam

    The info you wrote about is probably based on one of two early studies conducted in 1968 and 1977 that addressed the effect of stevioside on animals and noted the potential negative effects of stevioside on fertility. However, animals used in these studies were given extremely high doses of stevioside, nearly 6% of their total body weight daily. Numerous follow-up studies have been conducted that show stevioside has no effect on fertility, mating performance, pregnancy, number of fetuses or growth and fertility of offspring.

    Here is an excerpt from The European Stevia Center, reproduced for educational purposes:
    Stevioside is safe!
    by Prof. Jan M.C. Geuns
    Lab. Functional Biology, KULeuven

    “In 2004 researchers of the KULeuven (Belgium) organized an international symposium on “The Safety of stevioside”. Scientists from all over the world concluded that stevioside is safe, and that stevioside has not any effect on male or female fertility, nor on development and state of fetuses.

    It’s notable to point out that over the past 30 years, there have been more than 1,000 scientific studies published on stevia and its extract stevioside, none of which report any negative health consequences for humans as a result of consumption of stevia leaf or its extract.

    (Currently, stevia represents approximately 45% of the market share of sweet substances consumed in Japan. The Japanese, who strictly regulated artificial sweetners in the 1960’s to move away from increased chemicals in the food supply, use stevia to sweeten a wide variety of food products.)

  • cyn

    I like growing my own stevia and find the fresh leaf a cleaner taste than the powdered version. Why hasn’t the FDA approved stevia as a sweetener instead of as a food additive? The answer lies in the money connections to the sugar industry and sugar futures. Research it for yourself,there’s a lot more going on than children cutting cane!

  • acampbell

    Hi Mariam,
    Actually, the study pointing to organ lesions in rats was a fairly recently published study. While I’m not sure that all studies conclude that stevia is completely safe, I agree that the majority of them do. My intent was to point out some of the reasons why the FDA has not yet approved stevia; obviously it’s an individual’s decision whether to use stevia or not.

  • Mariam

    Hi Amy, thanks for your response.
    My nutrition professors believe that the reason the FDA hasn’t approved of stevia is because of the lobbying power and money that the artificial sweetner industry has.
    There are many more studies that point out the ill effects of aspartame, saccharin, sucralose, and other chemical sweeteners which have been approved by the FDA.
    I’m not sure FDA approval is about public safety as much as it is about money and power, as all-natural stevia has been shown in studies to be more ‘safe’ than chemical sweetners.

    Here’s an interesting read:

  • acampbell

    Hi Mariam. Your professors certainly could be right about the FDA – sometimes they work in mysterious ways! Research seems to be conflicting about the “harmfulness” of other sweeteners, however. And, to be honest, I’m a little skeptical as to the ability of Dr. Janet Hull, the creator of the Aspartame Detox Program (, to have “cured” her “disease” caused by aspartame. But, I’m all for finding safe, natural sweeteners, and relying less on chemicals. Thanks for your comments.



  • anne kee

    I think it is much safer to use then the artificial sweeteners, which are known to be bad yet are allowed in many foods. My Dr. told me to use stavia as its the ONLY one that does not increase blood sugar.
    Unfortunately I don’t like the taste but I have heard that different brands do taste differently.

    • Jacki Stanley Page

      I buy a brand called daforto on Amazon. Just brilliant, cheap, no additives, and tastes great! X

  • imreney

    I use Stevia every day. In my morning shake I also use Erythritrol to sweeten. One of my favorite liquid stevia products is English Toffee…Yum!

  • tmeadow

    I have been using stevia in a product call zinger. It has changed my life. I have type II diabetes and after using stevia I am off my medication. I have lost over 50 lbs. My blood pressure is normal and I’m off the blood pressure medication. I have started to exercise and with the above combination I am greatful that I found stevia. Also I subscribe to the Diabetes Self Management Magazine. Thank you for introducing me to Stevia. Tom

  • Joan

    Hi Amy – thanks for this interesting topic; Stevia. I have really enjoyed all of your articles; good info.

    I have used stevia for about 5 years with no ill effect but use very little any given day and not every day! I have done research also and am not concerned. I do believe that using commercial artificial sweeteners or other packaged food items more unsafe due to the ingredients allowed by the FDA. However, I never use any product that I can not pronounce and spell the word).

    I also use stevia to bake, and for coffee and tea or over fresh berries as a light dessert. I use just a few granules for coffee and tea and not more than 1/2 teaspoonful of stevia combined with 5 teaspoonfuls of ground cinnamon when baking my special cinnamon rolls (use carbalose flour; lower in carbs than white flour.) My glucose levels do not rise at all using stevia or enjoying my cinnamon roll. :-))

    The odd taste that people notice is perhaps due to using too much! I purchase stevia in bulk from our local natural food store. The bulk stevia that I purchase does not lump at all; it remains a light, fluffy powder. I do keep it refrigerated at all times.

    I believe that to use any of the other artificial sweeteners is more “chancy” than using stevia but it is a personal choice, of course.

  • Ephrenia

    My favorite brand is NuNaturals. I’ve never had the bitterness from this brand. I use the packets of White Stevia Powder.

    Someone else mentioned Splenda for Bakinf – this product is half sugar. I’ve learned that the reason you need a little sugar is for browning a baked product. It doesn’t take half. I use regular Splenda and add my own sugar at 1/4 substitute and everything browns nicely with fewer carbs than Splenda for Bakinf… and I use Bob’s red Mill Lo-Carb Baking mix instead of flour.

  • Dan

    I like NuNaturals better then the old one. I use it when I make spaghetti sauce. It seems to give it a better taste.

  • Charlotte

    Thanks for all the information. I have been using Splenda, because I have not been able to find Stevia locally; but will try the Internet.I have never had any trouble with Splenda, but have had headaches with aspertame. Wouldn’t it be wonderful to find the perfect sweetener?

  • sher

    Thank for the information. I sent the article to my friend who always uses stevia.
    Very interesting.

  • Bahamut

    Thanks for the information! There’s probably no such thing as a “perfect” sweetener but trying to find one with the less amount of side effects is hard especially when pharmaceuticals and the FDA decide to play hide and seek with facts.

  • mutto

    tmeadow posted a product called zinger.what is it?and where can you find it?

  • acampbell

    Hi mutto,

    I think tmeadow was referring to a product made by Celestial Seasonings, called Zingers To Go. These are individual-sized packages of flavored green or herb teas that are sweetened with Stevia. You can check them out on Celestial Seasoning’s website, or purchase them through Amazon.

  • Lyn

    I’ve been using stevia in coffee for a couple years and have begun growing the plant. What is the best way to use the plant? Is it the root that is used in a ground up fashion?

  • acampbell

    Hi Lyn,

    The leaves are where the sweetness is located in the stevia plant. You can use the leaves for making tea, and you can also grind up the leaves into a powder by using a food processor. Don’t use the stems, however, as they aren’t sweet. For more information on growing stevia, check out this link:

  • acampbell

    Just wanted to share some new information on stevia. Wisdom Natural Brands will soon be marketing a stevia-based sweetener called SweetLeaf. SweetLeaf has been sold as a dietary supplement for more than a decade. However, Wisdom has declared that SweetLeaf meets the GRAS (generally recognized as safe) criteria, apparently allowing it to be sold as a sweetener. Other companies, such as Cargill and Corn Products International, will be following suit, marketing their own stevia sweeteners and products in the near future. It will be interesting to see if and how the FDA responds. Stay tuned!

  • DDWagner

    It frustrates me to no end that the FDA would rather have the general public overweight from sugar or braindead from Aspertame rather than chance some financial cutbacks from the artificial sweetner camp. Has there been a grassroots campaign to let the FDA know how much we need a natural alternative to both? If so, how can we jump on?

    I was diagnosed with PCOS two years ago and have long had long mental lapses due to Diet Coke being my drink of choice for years. Cutting back on carbs has helped with my fertilitiy issue (I now have a wonderful son), and cutting back on aspertame has made my mind sharp again! I was introduced to Stevia a few months ago and it has become a staple in our family. I would LOVE to have more products available sweetened by it.

    Thanks for the dialogue!

  • mlgaiser

    has anyone heard of xylitol as a natural sweetner?It is extracted from birch bark and is 2 to 3 times sweeter than table sugar and far safer.Diabetes is a disease of poor carbohydrate
    utilization which means we must limit our intake of high carb foods.

  • acampbell

    Hi mlgaiser,
    Xylitol is a polyol, or sugar alchol, similar to sorbitol, maltitol, and mannitol. Sugar alcohols do occur naturally in fruits and vegetables, but they’re also manufactured from sucrose, glucose and starch. Xylitol contains about 2 calories per gram, whereas sucrose contains 4 calories per gram. So, it contains half the calories and carbs as regular sugar (it’s not a calorie or carb-free sweetener). Xylitol can help prevent dental caries by inhibiting the growth of bacteria in the mouth, so it’s often added to toothpastes and mouthwash. Otherwise, as with other sugar alcohols, too much xylitol can cause gastrointestinal upset and/or diarrhea, since sugar alcohols are only partially digested. This sweetener is found in sugar-free products, but can also be purchased and used as a sweetener (although is not well-suited for baking).

  • buyerbeware

    The studies do not seem to be that conclusive about the effects of stevia on fertility. To say that large Paraguayan families is proof that stevia has no negative effect on fertility is like saying that the decline in Japan’s birth rate starting at around 1970, is linked to the introduction and popular use of Stevia at that time.

  • Angie

    Truvia, the brand name of a Stevia product, has been on the market now for at least a year. Their web site says their product has been approved by the FDA. It’s sold in the regular grocery store aisle, right next to Splenda and the other sweeteners. In moderation, it’s probably not harmful. Too much of just about anything can be harmful just about everyone. Stevia is natural, as opposed to Aspartame, which believe it or not is a chemical. Many chemicals are “natural” but they are not meant to be ingested into the body. Aspartame breaks down in the blood stream as formaldehyde and methanol–not something most people would consume by choice.

    • paulalovescats

      Natural is not the opposite of chemical. Everything’s a chemical, whether it was made by people or nature.

  • acampbell

    Thanks, Angie. To clarify, the FDA agreed to put only a highly purified form of stevia called rebiana (rebaudioside A) on its GRAS (generally recognized as safe) list last December. This is different from stevia, which generally refers to a crude preparation of dried stevia leaves. Rebiana is a purified extract of the stevia leaf and contains at least 97% rebaudioside. This is the only form of stevia approved for use in foods and beverages. PureVia, Truvia, SweetLeaf, and SunCrystals are a few of the new brands of stevia-based sweeteners that you’ll see in the grocery store.

  • Dnick

    I have type 2 diabetic and have today bought Stevia as recommended by my health professional. I found this article helpful. I will only use it for tea and coffee.

  • philip

    Stevia fue usado por los Incas en el Perú, antes que se descubra Paraguay o Brasil, (infórmense antes de hacer sus comentarios).

  • paulalovescats

    Hey, people! You give ANYTHING to mice or rats in thousands of times the normal dose, it’ll do things to them.

  • Doc

    I have grown to prefer stevia to sugar. It sweetens better with far less product. As for now, I’ll take my chances on whether or not it is safe. I like it. P.S. I have type 2 diabetes.

  • Justin Elkins

    This article’s over a decade old—time for an update, don’t ya think?