Stevia leaf extract is often considered a safe and healthy sugar substitute, potentially reducing calorie intake, blood sugar levels, and the chance of developing cavities. However, some safety concerns exist.

This article examines stevia’s safety to help determine whether you should use it.

Stevia is a natural sweetener derived from the leaves of the stevia plant (Stevia rebaudiana).

As it has zero calories but is 200 times sweeter than table sugar, it’s a popular choice for many people looking to lose weight and decrease sugar intake ((1, 2, 3, 4).

This sweetener has also been associated with several health benefits, including lower blood sugar and cholesterol levels (5, 6).

Nevertheless, commercial stevia products vary in quality.

In fact, many varieties on the market are highly refined and combined with other sweeteners — such as erythritol, dextrose, and maltodextrin — which may alter its potential health effects.

Meanwhile, less processed forms may be lacking in safety research.

Forms of stevia

Stevia is available in several varieties, each differing in its processing method and ingredients.

For instance, several popular products — such as Stevia in the Raw and Truvia — are really stevia blends, which are one of the most heavily processed forms of stevia.

They’re made using rebaudioside A (Reb A) — a type of refined stevia extract, alongside other sweeteners like maltodextrin and erythritol (7).

During processing, the leaves are soaked in water and passed through a filter with alcohol to isolate Reb A. Later, the extract is dried, crystallized, and combined with other sweeteners and fillers (1).

Pure extracts made only from Reb A are also available as both liquids and powders.

Compared to stevia blends, pure extracts undergo many of the same processing methods — but are not combined with other sweeteners or sugar alcohols.

Meanwhile, green leaf stevia is the least processed form. It’s made from whole stevia leaves that have been dried and ground.

Although the green leaf product is typically considered the purest form, it’s not as thoroughly studied as pure extracts and Reb A. As such, research is lacking on its safety.

Summary

Stevia is a zero-calorie sweetener. Commercial varieties are often highly processed and mixed with other sweeteners.

Steviol glycosides, which are refined extracts of stevia like Reb A, are recognized as safe by the Food and Drug Administration (FDA), meaning that they can be used in food products and marketed in the United States (8).

On the other hand, whole-leaf varieties and raw stevia extracts are currently not approved by the FDA for use in food products due to a lack of research (8).

Regulatory agencies like the FDA, the Scientific Committee on Food (SCF), and the European Food Safety Authority (EFSA) define the acceptable daily intake of steviol glycosides as up to 1.8 mg per pound of body weight (4 mg per kg) (9).

Stevia safety in certain populations

Although many stevia products are generally recognized as safe, some research indicates that this zero-calorie sweetener may impact certain people differently.

Due to health conditions or age, various groups may want to be especially mindful of their intake.

Diabetes

You may find stevia helpful if you have diabetes — but be careful about which type to choose.

Some research indicates that stevia may be a safe and effective way to help manage blood sugar levels in people with type 2 diabetes.

In fact, one small study in 12 people with this condition showed that consuming this sweetener alongside a meal led to greater decreases in blood sugar levels compared to a control group given an equal amount of corn starch (2).

Similarly, an 8-week study in rats with diabetes noted that stevia extract decreased levels of blood sugar and hemoglobin A1C — a marker of long-term blood sugar control — by over 5% compared to rats fed a control diet (10).

Keep in mind that certain stevia blends may contain other types of sweeteners — including dextrose and maltodextrin — that can increase blood sugar levels (11, 12).

Using these products in moderation or opting for pure stevia extract can help maintain normal blood sugar levels if you have diabetes.

Pregnancy

Limited evidence exists on the safety of stevia during pregnancy.

However, animal studies suggest that this sweetener — in the form of steviol glycosides like Reb A — does not negatively impact fertility or pregnancy outcomes when used in moderation (13).

Additionally, various regulatory agencies consider steviol glycosides safe for adults, including during pregnancy (9).

Still, research on whole-leaf stevia and raw extracts is limited.

Therefore, during pregnancy, it’s best to stick to FDA-approved products that contain steviol glycosides rather than whole-leaf or raw products.

Children

Stevia can help cut down on added sugar consumption, which could be especially beneficial for children.

According to the American Heart Association (AHA), a higher intake of added sugar could increase children’s risk of heart disease by altering triglyceride and cholesterol levels and contributing to weight gain (14).

Swapping added sugar for stevia could potentially minimize these risks.

Steviol glycosides like Reb A have been approved by the FDA. However, it’s especially important to monitor intake in kids (8).

This is because it’s much easier for kids to reach the acceptable daily limit for stevia, which is 1.8 mg per pound of body weight (4 mg per kg) for both adults and children (9).

Limiting your kid’s consumption of foods with stevia and other sweeteners, such as sugar, can help prevent adverse side effects and support overall health.

Summary

Steviol glycosides like Reb A are approved by the FDA — while whole-leaf and raw extracts are not. Stevia may impact certain groups differently, including children, pregnant women, and people with diabetes.

Although generally recognized as safe, stevia may cause adverse effects in some people.

For example, one review noted that zero-calorie sweeteners like stevia could interfere with concentrations of beneficial gut bacteria, which play a central role in disease prevention, digestion, and immunity (15, 16, 17).

Another study in 893 people found that variations in gut bacteria could negatively impact body weight, triglycerides, and levels of HDL (good) cholesterol — known risk factors for heart disease (18).

Some research even suggests that stevia and other zero-calorie sweeteners could lead you to consume more calories throughout the day (19).

For instance, one study in 30 men determined that drinking a stevia-sweetened beverage caused participants to eat more later in the day, compared to drinking a sugar-sweetened beverage (20).

What’s more, a review of seven studies discovered that routine consumption of zero-calorie sweeteners like stevia may contribute to increased body weight and waist circumference over time (21).

Additionally, certain products with stevia may harbor sugar alcohols like sorbitol and xylitol, which are sweeteners sometimes associated with digestive issues in sensitive individuals (22).

Stevia may also reduce blood pressure and blood sugar levels, potentially interfering with medications used to treat these conditions (23).

For best results, moderate your intake and consider reducing consumption if you experience any negative side effects.

Summary

Stevia may disrupt your levels of healthy gut bacteria. Counterintuitively, some evidence even suggests that it could increase food intake and contribute to a higher body weight over time.

Stevia is a natural sweetener linked to numerous benefits, including lower blood sugar levels.

While refined extracts are considered safe, research on whole-leaf and raw products is lacking.

When used in moderation, stevia is associated with few side effects and can be a great substitute for refined sugar.

Keep in mind that more research on this sweetener is needed.