Stevia Side Effects: What You Need to Know About This Natural Sweetener

Stevia has become one of the most popular natural sweeteners on the market, but many people don’t fully understand what they’re actually consuming when they use products labeled as “stevia.” Understanding the differences between various stevia products and their potential side effects is crucial for making informed decisions about your health.

What Is Stevia?

Stevia, scientifically known as Stevia rebaudiana, is a plant belonging to the chrysanthemum family within the Asteraceae family. Native to South America, this plant has been used for centuries as a natural sweetener.

However, there’s a significant distinction between the stevia plant you might grow in your garden and the stevia sweetener products available at your local grocery store. Commercial stevia products like Truvia and Stevia in the Raw don’t contain the whole stevia leaf. Instead, they’re manufactured from a highly refined extract called rebaudioside A, commonly referred to as Reb-A.

Reb-A is approximately 200 times sweeter than regular table sugar, which means you need only a tiny amount to achieve the desired sweetness. Many commercial stevia products actually contain very little actual stevia and are instead blended with other ingredients like erythritol (a sugar alcohol), dextrose (glucose), or maltodextrin to create bulk and improve texture.

Common Stevia Side Effects

While stevia is generally recognized as safe by the U.S. Food and Drug Administration (FDA), some people may experience side effects, particularly when consuming products that contain additional ingredients.

Digestive Issues

One of the most commonly reported side effects of stevia products involves digestive discomfort. This is typically not from the stevia itself, but from sugar alcohols like erythritol that are blended into many commercial stevia sweeteners. These ingredients may cause:

• Bloating and gas
• Abdominal cramping
• Diarrhea
• Nausea

If you’re sensitive to sugar alcohols, look for stevia products that don’t contain erythritol or other similar additives.

Taste-Related Concerns

While not a health side effect per se, many people find stevia’s taste challenging. Stevia has a distinctive, slightly bitter, licorice-like aftertaste that can be off-putting. This taste profile may be more pronounced in some products than others, depending on the formulation and additional ingredients used.

Potential Allergic Reactions

Though rare, some individuals may experience allergic reactions to stevia, particularly those who are allergic to plants in the Asteraceae family, which includes ragweed, chrysanthemums, marigolds, and daisies. Symptoms might include:

• Skin irritation or hives
• Difficulty breathing
• Dizziness

If you suspect an allergic reaction, discontinue use immediately and consult with a healthcare professional.

Blood Sugar and Blood Pressure Effects

While stevia can be beneficial for blood sugar management, there are some considerations to keep in mind. Raw, unprocessed stevia may potentially lower blood pressure too much in some individuals, particularly those already taking blood pressure medications.

Additionally, commercial stevia products containing dextrose or maltodextrin can affect blood sugar levels, albeit minimally. These ingredients add small amounts of carbohydrates that can accumulate if you consume stevia products frequently throughout the day.

Impact on Gut Health

Recent research has raised questions about the potential impact of nonnutritive sweeteners, including stevia, on beneficial gut bacteria. Some studies suggest that regular consumption of these sweeteners might disrupt the balance of intestinal flora, though more research is needed to fully understand this relationship.

Health Benefits of Stevia

Despite potential side effects, stevia offers several health benefits that make it an attractive sugar alternative for many people.

Zero to Low Calorie Content

As a nonnutritive sweetener, stevia contains virtually no calories. This makes it appealing for individuals trying to manage their weight or reduce overall calorie intake. However, it’s important to note that research on the effectiveness of artificial sweeteners for weight loss remains inconclusive and may depend on various factors including consumption amount and timing.

Blood Sugar Management

For people with diabetes or those monitoring their blood glucose levels, stevia may be a helpful tool. Research has shown that stevia can help maintain stable blood sugar levels without causing the spikes associated with regular sugar consumption.

Studies have demonstrated that stevia may actually help lower both insulin and glucose levels while keeping people feeling satisfied after meals, despite consuming fewer calories.

Cholesterol Management

Some research suggests that stevia leaf powder may help manage cholesterol levels. Studies have found that regular stevia consumption may help reduce total cholesterol, LDL (“bad”) cholesterol, and triglycerides while increasing HDL (“good”) cholesterol levels. However, it’s unclear whether occasional use in smaller amounts would produce the same benefits.

Potential Cancer-Fighting Properties

Emerging research has explored stevia’s potential role in cancer prevention and treatment. Studies have found that stevioside, a glycoside compound found in stevia plants, may help promote cancer cell death in certain types of breast cancer cells and reduce specific pathways that support cancer growth.

Research has also shown that various stevia glycoside derivatives demonstrated toxic effects on specific leukemia, lung, stomach, and breast cancer cell lines. While these findings are promising, more research is needed before any definitive conclusions can be drawn.

Is Stevia Safe During Pregnancy?

The safety of stevia during pregnancy depends on which type you’re using. Refined stevia products made with Reb-A are considered safe to use in moderation during pregnancy. However, pregnant women who are sensitive to sugar alcohols should choose brands that don’t contain erythritol.

In contrast, whole-leaf stevia and crude stevia extract—including stevia plants you might grow at home—are not recommended during pregnancy. While it may seem counterintuitive that a highly refined product would be safer than a natural one, the reason is simple: Reb-A has been thoroughly evaluated for safety during pregnancy, while natural stevia hasn’t.

Currently, there isn’t sufficient research to confirm that whole-leaf stevia or crude stevia extract is safe for pregnant women and their developing babies.

Different Types of Stevia Products

Refined Stevia (Reb-A)

This is the most common type found in stores. It’s highly processed but has been evaluated and approved by the FDA as generally recognized as safe. Available in liquid, powder, and granulated forms, refined stevia is what you’ll find in products like Truvia and Stevia in the Raw.

Whole-Leaf Stevia

This is the least processed form, consisting of dried stevia leaves. While you can grow and use this at home, it’s not approved by the FDA for commercial use in processed foods and beverages due to insufficient safety data.

Crude Stevia Extract

This is a partially processed product that falls between whole-leaf and refined stevia. Like whole-leaf stevia, it hasn’t been approved by the FDA for commercial use.

How to Use Stevia as a Sugar Substitute

Stevia can replace table sugar in many applications, but there are some important considerations to keep in mind:

General Guidelines

Because stevia is significantly sweeter than sugar, you’ll need much less. Typically, a small pinch of stevia powder equals about one teaspoon of table sugar. However, this can vary by brand, so always check the product’s conversion guidelines.

Best Uses for Stevia

• Sweetening hot or cold beverages like coffee, tea, and lemonade
• Adding to smoothies and protein shakes
• Sprinkling on cereal or oatmeal
• Sweetening plain yogurt
• Making homemade sauces and salad dressings

Baking with Stevia

Baking with stevia can be tricky because sugar provides more than just sweetness—it also contributes to texture, volume, and browning. When using stevia in baked goods:

• You may need to add extra liquid or bulking ingredients like applesauce, mashed bananas, or additional eggs
• Expect a possible licorice-like aftertaste
• Start by replacing only half the sugar in your recipe and adjust from there
• Be prepared for some trial and error to achieve the desired results

Who Should Avoid or Limit Stevia?

While stevia is safe for most people, certain individuals should exercise caution:

• People with ragweed allergies: Those allergic to ragweed or related plants may also react to stevia
• Individuals on blood pressure medications: Raw stevia may enhance the effects of these medications, potentially causing blood pressure to drop too low
• People taking diabetes medications: While refined stevia is generally safe, it’s important to monitor blood sugar levels and consult with your doctor
• Those with digestive sensitivities: If you’re sensitive to sugar alcohols, avoid stevia products containing erythritol or similar additives
• Pregnant women: Stick to refined stevia products and avoid whole-leaf or crude stevia extract

Making an Informed Choice

When selecting a stevia product, read labels carefully. Look for:

• The type of stevia used (Reb-A is the safest, most studied option)
• Additional ingredients, particularly sugar alcohols if you’re sensitive to them
• The conversion ratio for replacing sugar
• Whether the product is suitable for your intended use (beverage, baking, etc.)

The Bottom Line

Stevia products made with Reb-A are considered safe for most people, including those with diabetes and pregnant women when used in moderation. While side effects are generally rare and mild, they can occur, particularly in products containing sugar alcohols or in people with certain sensitivities.

The potential benefits of stevia—including zero calories, blood sugar stability, and possible cholesterol management—make it an attractive sugar alternative. However, more research is needed to fully understand its long-term effects on weight management, metabolic health, and gut bacteria.

Whole-leaf stevia and crude stevia extract haven’t been as thoroughly studied and aren’t approved for commercial use. While many people use home-grown stevia without apparent problems, there isn’t enough research to confirm its safety, especially for pregnant women or people with serious health conditions.

If you’re considering using stevia, especially if you have diabetes, heart disease, high blood pressure, or another serious medical condition, consult with your healthcare provider first. They can help you determine whether stevia is appropriate for your individual situation and advise you on safe usage amounts.

Remember that while stevia can be a useful tool for reducing sugar intake, it’s not a magic solution for health or weight management. A balanced diet, regular physical activity, and overall healthy lifestyle habits remain the foundation of good health.

Sources:

• U.S. Food and Drug Administration – High-Intensity Sweeteners
• National Institutes of Health – Effects of Stevia on Glucose and Insulin Levels
• National Institutes of Health – Nonnutritive Sweeteners and Gut Health
• PubMed – Stevioside and Cancer Cell Death
• Mayo Clinic – Artificial Sweeteners and Sugar Substitutes