Stevia has been used for hundreds of years in South and Central America with no widespread reports of toxic effects. Stevia extract and its main sweet compounds have also been safely consumed since the 1970s in Japan, both as table-top sweeteners and as an ingredient in food products. Despite the approval of stevia and its steviol compounds as sweeteners in many countries, stevia still doesn't have the same level of approval in the United States and Britain.(5, 8, 15)
Safety is a complex issue. It's often fraught with controversy and conflicts of interest, so it is difficult to give an absolute "yes" or "no" answer to this question. Further complicating the matter, food authorities must determine the safety of stevia and its main components:(3, 4, 15-18)
Steviol compounds; specifically, the two main sweet compounds in stevia leaves:
That said, we can provide you with the current approvals by food safety authorities in the U.S. and overseas:(4, 15-19)
Stevia Form/Compound | U.S. FDA Approval | JECFA Approval | European Food Safety Authority (EFSA) |
---|---|---|---|
Whole stevia/stevia leaves or crude extract | Dietary Supplement Only | Dietary Supplement Only | Dietary Supplement Only |
Stevioside | Dietary Supplement Only | Sweetener/Food Additive | Sweetener/Food Additive |
Rebiana (rebaudioside A) | GRAS - Sweetener/Food Additive | Sweetener/Food Additive | Sweetener/Food Additive |
In 2006 the Joint FAO/WHO Expert Committee on Food Additives (JECFA) issued a temporary ADI of 0-2 mg/kg of body weight for stevia's steviol compounds. The committee asked for additional research before establishing a permanent ADI. Based on the results of those studies, JECFA removed the temporary ADI status for steviol glycosides in June, 2008. They published a permanent ADI of 0-4 mg/kg body weight in its 2009 report.(17, 18)
Stevia has been in use in the United States for decades as a dietary supplement. Currently the FDA still maintains concerns about the safety of both the whole plant stevia and its stevioside compound as food additives. This is due to some studies that suggest they may have mutagenic effects at extremely high doses in animals.(3-5, 8, 15, 17, 18)
In 2008, one component of stevia was granted GRAS status as a food additive by the FDA. The compound - rebaudioside-A (aka rebiana or reb-A) - is one of two primary steviol glycoside components that make stevia sweet. The other is stevioside. Both do not raise blood glucose levels like most sugar does. Some companies are marketing sweeteners and products made from this stevia-derived compound (such as Coca Cola/Cargill's Truvia®, PepsiCo's SoBe® Life Water and PureVia™).(3, 4, 15)
The Center for Science in the Public Interest (CSPI) has criticized the FDA for granting GRAS to rebiana. Their position is that rebiana hasn't been tested enough to call it safe.(3, 15)
ADI is the amount of a substance that can be safely consumed daily over a lifetime, based on current research. For countries who follow JECFA guidelines, the maximum acceptable intake for stevia and its steviol compounds is 4 mg per kg of body weight. FDA guidelines calls for a maximum of 12 mg/kg body weight daily for rebiana.(18, 20, 21)
There have been conflicting reports about stevia's impact on blood pressure and blood glucose levels. Some experts suggest people taking the following medications use caution when using stevia and its compounds:(16)
As always, we advise you to consult with your health care provider about your individual concerns.
Some authorities recommend that pregnant women not use stevia (the herb) if pregnant. However, according to the American Dietetic Association, FDA-approved sweeteners (such as stevia's rebiana) are considered "generally safe" for use by pregnant women, within moderation.(4, 16, 20)
The main regulatory food safety agencies worldwide go further than the FDA and state that high-purity steviols extracted from stevia leaves, which includes both stevioside and rebiana, are safe to consume in food and beverages. The ADI is determined using a safety factor of 100, which essentially gives a margin to account for differences in animals, average humans, and people more sensitive to toxicity. This includes women, children, and the elderly.(4, 21)