Johnathan Walker:Stevia was once banned in the US: Is the sugar substitute bad for you?

While the United States has only been continuously using artificial sweeteners since the Food and Johnathan WalkerDrug Administration (FDA) approved Nutrasweet in 1981, other cultures have been using sugar substitutes for much longer. In the early tenth century, for example, Romans manufactured a sweetener by boiling grape juice in lead pots until it became a syrup they could use to sweeten food and beverages. China and other parts of Asia have used tea leaves for millennia to manufacture and sweeten that iconic beverage. 

More recently though, and dating back a few hundred years per one study, South America has been using the leaves of the stevia rebaudiana plant as their version of a sugar substitute. Eventually, other areas of the world adopted this stevia sweetener as well until, over the past decade, it has become a staple in many grocery stores, diners, and home kitchens.

What is stevia? 

Stevia is a natural sugar substitute or artificial sweetener that is known for "its incredibly sweet taste and low-calorie content," says Jen Messer, a nutrition consultant and registered dietitian at Jen Messer Nutrition. She explains that stevia gets its sweetness from a group of compounds called steviol glycosides that are found in the stevia plant's leaves. These compounds are behind this sugar alternative "providing up to 300 times the sweetness of table sugar," says Nikki Cota, MS, RDN, an outpatient clinical dietician for Mayo Clinic.

Once extracted and purified, stevia is processed into various forms that include liquid drops, powdered extracts, and granulates "that can be used for cooking and baking," says Messer. Its popular packet form is similar in appearance to other sugar substitutes such as Sweet 'N Low, Splenda and Equal, and it's distributed under brand names like Truvia, SweetLeaf and Stevia in the Raw.

Stevia is categorized as a high-intensity sweetener along with other sugar substitutes such as aspartame, sucralose and neotame − all different than the sugar alcohol type of artificial sweeteners that include erythritol, isomalt and sorbitol.

Is stevia bad for you? 

Though stevia was initially banned in the U.S. because some studies suggested it may be linked to cancer, it's no longer prohibited. In fact, in 2008, stevia was granted GRAS status by the FDA - which stands for "Generally Recognized As Safe." 

Since then, stevia has been considered safe to use in recommended doses, but may still have some negative side effects. "For some people, stevia products can cause gastrointestinal symptoms such as nausea, bloating, diarrhea and abdominal pain when consumed in high amounts," says Lisa Young, PhD, RDN, an adjunct professor of nutrition at New York University and author of "Finally Full, Finally Slim."

It has also been linked to headaches, numbness and dizziness for some users. "And stevia can interact with certain medications, so it's important to talk to your doctor before using it if you are taking any medication or have a health condition," cautions Messer. 

What's more, a recent meta-analysis of more than 50 studies found that artificial sweeteners used in beverages generally are associated with a higher risk of "hypertension, cardiovascular disease and all-cause mortality," says Donald Hensrud, MD, an associate professor of preventive medicine and nutrition for Mayo Clinic and the editor of “The Mayo Clinic Diet.”

What are the advantages of stevia? 

But there still may be upsides to using the artificial sweetener, especially as a sugar substitute in beverages to replace sugar-filled drinks soda. Sugar-sweetened soft drinks have been linked to obesity, liver cancer, Type 2 diabetes, decreased bone health and even higher risks of heart disease, per Harvard Medical School and artificially-sweetened drinks in moderation could help some people avoid such outcomes. Stevia also has the benefit of having "a low impact on blood sugar levels, making it a sought-after option for people managing diabetes," says Messer. 

On the practical side, stevia is also known to be heat stable with a long shelf life, "which makes it a versatile ingredient for a wide range of foods and drinks," says Messer. Because of many of its known advantages, she says, "if my clients are looking for a natural and low-calorie sweetener, I tell them that stevia is a good option."

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