|Our little stevia plant.|
I say stevia is “the healthy sweetener” not because the herb is especially nutritious itself, but because its high sweetness allows us to reduce the amount of sugar in our baking. Consuming high amounts of natural sugars is unhealthy (glucose, fructose, and sucrose), while artificial sweeteners (aspartame, saccharin, sucralose, etc) are downright frightening to the health-conscious. Stevia extract can be up to 300 times sweeter than common table sugar, it has zero calories, and it scores a zero on the gycemic index (it doesn’t raise blood sugar levels).
Kelly’s sweetening technique is to use a tiny amount of stevia, along with a small amount of other natural sweetener (honey or coconut sugar). For instance, the chocolate bundt cake in her new cookbook uses only 1/2 teaspoon of stevia extract and 1/2 a cup of honey. Meanwhile, the typical bundt cake recipes seen online call for 2 & 1/2 cups of sugar!
We don’t rely completely on stevia to sweeten our baking, because too much will give a bitter flavor. Paired with honey or coconut sugar, a little stevia is unnoticeable in baked goods. In coffee or tea we use no more than a couple drops.
WHAT IS STEVIA?
There are hundreds of plant species within the genus Stevia, but only one, Stevia rebaudiana, is used as a sweetener. It is a perennial herb that is native to northeastern Paraguay. In the wild it grows to be 30 to 50 cm tall, and it blooms with small, primarily white flowers. The leaves have a very sweet taste, which has made the plant valuable as a food sweetener.
In the Guaraní Indian language stevia is called Caá hê-é, which means “sweet herb”. For at least one hundred years stevia leaves have been used by native Paraguayan people to sweeten their mate drinks. The tradition may go back much farther, but there just isn’t clear surviving evidence to say so. It is theorized that this tradition began no earlier than the arrival of the Spaniards in the 16th century. Stevia was first reported to the scientific world in 1901 by the British consul Cecil Gosling and in 1905 by an Italian-Swiss botanist, Moisés Bertoni. Decades of experimentation and study followed. In the 1930s French chemists identified the two compounds giving the leaves their sweetness. These sweet glycosides were named stevioside and rebaudioside A.
The plant began to be grown commercially on a large scale in the 1960s after stevia’s potential as a sugar substitute became widely known. In 1970 stevia extract arrived on the Japanese market where it has become a very common sweetener of food and beverages. In the 1980s stevia began to be more widely consumed in Brazil and other South American countries, South Korea, and Western Europe. Stevia first became available in the United States as an ingredient in tea. American artificial sweetener corporations actually managed to get it banned for 4 years, but today it has full FDA approval and is widely available as a sweetener (more on this below). Stevia is grown commercially for export in Brazil, Canada, China, Japan, Parguay, South Korea, and Thailand.
Most of us Americans didn’t grow up with stevia, so it is understandable that there may be some suspicion of this “new” sweetener. However, stevia’s safety has been established by over a century of known human consumption and decades of scientific testing.
“The safety of the chemical compound stevioside and of whole stevia leaf has been evaluated extensively in laboratory tests looking at possible toxic, genetic, or cancer-causing effects. Both have been determined to be safe when used as a sweetener.” —National Geographic Guide to Medicinal Herbs, p. 349
There has been no evidence of adverse reactions due to consumption of stevia in humans reported in medical literature. However, the plant has been the subject of some controversy:
In 1968 an article published in Science magazine raised concern about stevia's affect on fertility. The authors Planas and Kuc claimed that they encountered tribes in Paraguay who had a tradition of using the stevia plant as a contraceptive. They went on to say that their experiment with rats showed a reduction in fertility after consuming stevia. Although this report is often cited, its findings have never been duplicated. Numerous studies by other scientists have found no affect on fertility in male or female rats. The Planas and Kuc eperiment appears to be flawed, and some doubt has been placed on their report of the tribes. In 1985 two botanists, A. Douglas Kinghorn and Djaja Djendoel Soejarto conducted field surveys across the same region of northeastern Paraguay and were unable to find people who used stevia as a contraceptive.
As a personal anecdote, we can say that Kelly became pregnant with our third child in only one month of trying. This was at age 33 after nine years of regular stevia consumption. The home country of stevia, Paraguay, has normal fertility rates.
Stevia was introduced to American consumers in the 1980s as an ingredient in teas made by Celestial Seasonings and Lipton. Concerned about the competition posed by the foreign-grown stevia, American artificial sweetener corporations (NutraSweet in particular) pressured the Food and Drug Agency to prohibit stevia. Ignoring the decades of safety testing and consumption in Japan, the FDA banned imports of stevia in 1991. The Dietary Supplement Health and Education act lifted the ban in 1995. This allowed stevia to be sold in the US again, but only if it was labeled as a “dietary supplement”. It was not commercialy available as sweetener in food and beverages again until 2008. This came about because the American corporations Cargill and The Coca-Cola Company wanted to develop their own stevia product for sale in the US. In 2009 FDA granted all stevia products its Generally Regarded as Safe (GRAS) status. The same approval was given in Canada in 2012.
Just as common foods like apples, bananas, etc. can cause allergic reactions, it is thought that some people might be allergic to stevia (most likely those who have a known allergy to ragweed or related plants).
Stevia can be found as an ingredient in a variety of commercial food and drink products, but for this post we’re only concerned with the stevia products for home cooking. Stevia is available as ground leaf powder, a powdered extract, and a liquid extract. Kelly prefers the liquid extract made by three companies: NOW Foods, NuNaturals, and SweetLeaf. The sweetness in their products (stevioside and rebaudioside A) is extracted from ground non-GMO stevia leaves using only cold purified water and filtering system.
We do not use stevia brands PureVia, Stevia in the Raw, or Truvia. These companies use a chemical process to extract stevioside and rebaudioside A, and their products use GMO ingredients.
Hawke, Jenny. “The Bittersweet Story of the Stevia Herb” in NEXUS Magazine, Volume 10, Number 2. 2003.
Johnson, Rebecca, et al. National Geographic Guide to Medicinal Herbs: The World’s Most Effective Healing Plants, National Geographic, 2012.
Kinghorn, A. Douglas. Stevia: The Genus Stevia. CRC Press, 2012.
This monograph is a collection of scientific papers by botanists and chemists. The papers most useful for this post were:
- Soejarto, Djaja Djendoel. “Botany of Stevia and Stevia rebaudiana”
- Soejarto, Djaja Djendoel. “Ethnobotany of Stevia and Stevia rebaudiana”
- Huxtable, Ryan. “Pharmacolgy and toxicology of stevioside, reaudioside A, and steviol.”
- Mizutani, Kenji and Tanaka, Osamu. “Use of Stevia rebaudiana sweeteners in Japan.”
Tucker, Arthur O. and DeBaggio, Thomas. The Encyclopedia of Herbs: A Comprehensive Reference to Herbs of Flavor and Fragrance. Timber Press, 2009.