What are the side effects of consuming stevia?

January 8, 2026 •

3 min read

While the FDA has designated highly purified stevia as 'generally recognized as safe' (GRAS), it's important to understand the potential adverse reactions. These potential side effects of consuming stevia range from mild digestive issues to more significant concerns for specific health conditions.

Quick Summary

Potential adverse reactions from stevia use include bloating, nausea, gas, allergic reactions, headaches, and drug interactions, particularly with medications for blood pressure and diabetes. Concerns exist about its safety for pregnant women and those with certain health conditions.

Key Points

Digestive Distress: Stevia products containing sugar alcohols like erythritol can cause gas, bloating, and diarrhea in sensitive individuals.
Blood Pressure Changes: Stevia may lower blood pressure, which can be beneficial for some but risky for people with low blood pressure or those taking antihypertensive medication.
Allergic Reactions: Though uncommon, individuals with allergies to plants in the Asteraceae family (like ragweed) may experience a cross-reactive allergic reaction to stevia.
Drug Interactions: Stevia can interact with certain medications, including those for diabetes and high blood pressure, potentially causing blood glucose or blood pressure to drop too low. Stevia's diuretic effect can also impact lithium levels.
Purity Matters: The FDA has approved highly purified stevia extracts as safe, but unprocessed, crude leaf extracts lack sufficient safety data and are not approved for commercial use.
Pregnancy Concerns: Due to limited research on whole-leaf and crude forms, pregnant individuals should consult a doctor before consuming stevia.
Bitter Aftertaste: Some people report a bitter, licorice-like aftertaste, especially with less-refined stevia products.

Potential Side Effects of Stevia Consumption

While highly purified stevia extract is generally considered safe, some individuals may experience adverse effects. It's important to note that many concerns are linked to the additives often found in commercial stevia products rather than the stevia glycosides themselves.

Digestive Concerns

Many digestive issues associated with stevia products stem from added ingredients like sugar alcohols (erythritol, xylitol) used as bulking agents. These can cause:

Bloating
Gas
Cramping
Nausea
Diarrhea

These symptoms occur because sugar alcohols are not fully absorbed and can be fermented by gut bacteria.

Allergic Reactions

Although rare, allergic reactions are possible, particularly for those sensitive to plants in the Asteraceae family (ragweed, daisies, chrysanthemums). Stevia belongs to this family, potentially causing cross-reactivity. Symptoms can range from skin issues to difficulty breathing.

Impact on Blood Pressure and Drug Interactions

Stevia may have a blood pressure-lowering effect. While potentially beneficial, this requires caution for individuals with low blood pressure or those taking blood pressure medications, as it could lead to dizziness or excessive drops in pressure. Stevia is also a diuretic. This can affect how the body processes certain medications, such as lithium, potentially leading to increased levels and severe side effects. Consult a doctor if you take medication for blood pressure or other conditions.

Concerns for Specific Health Conditions

Diabetes: Stevia's potential to lower blood sugar could interact with diabetes medications, increasing hypoglycemia risk. Some blends also contain sugars like dextrose. Diabetics should read labels and consult their doctor.
Pregnancy: While purified stevia is often considered safe in moderation, research on whole-leaf or crude stevia during pregnancy is limited. Some opinions advise caution due to insufficient data on fetal development effects. Pregnant individuals should consult a healthcare provider.
Liver and Kidney: Older concerns about raw stevia affecting these organs exist, but more recent studies suggest purified stevia may even offer some protection to kidneys. However, animal studies with high intake have shown elevated enzyme levels, indicating a need for more human data.

Purified vs. Crude Stevia

Side effects can depend on the type of stevia consumed.


Feature	Highly Purified Stevia (e.g., Reb-A)	Whole-Leaf / Crude Extracts
Safety Status	FDA-approved, GRAS	Not FDA-approved for food additive use
Potential Side Effects	Few reported; additives may cause digestive issues	Concerns (kidneys, reproductive, cardiovascular) due to lack of research
Taste	Less bitter aftertaste	Often bitter/licorice-like aftertaste

Minimizing Risks

To reduce potential side effects:

Choose highly purified products and check ingredients for additives.
Use in moderation within established acceptable daily intake levels.
Consult a healthcare provider if you have medical conditions, are pregnant, or take medications.

Conclusion

Highly purified stevia extracts are a popular low-calorie sweetener and generally considered safe. However, potential side effects, often linked to additives like sugar alcohols, can include digestive upset, rare allergic reactions, and interactions with certain medications, particularly for blood pressure and diabetes. Limited data on whole-leaf and crude forms means caution is advised. By understanding the type of stevia used and personal health factors, individuals can make informed choices. For more information on stevia and potential interactions, resources like WebMD provide detailed insights.

Frequently Asked Questions

Yes, some people experience digestive issues like bloating, gas, and cramping after consuming stevia, but this is often caused by sugar alcohols such as erythritol that are added to stevia blends, rather than the stevia extract itself.

Stevia has been observed to have a blood pressure-lowering effect. This can be a concern for individuals who already have low blood pressure or those taking medication for hypertension, and they should consult a doctor.

Allergic reactions to stevia are rare but possible, particularly for those with a known allergy to plants in the daisy family (Asteraceae), which includes ragweed, as cross-reactivity can occur.

Yes, stevia can interact with certain medications. Its potential effects on blood sugar and blood pressure mean it can interfere with diabetes medications and antihypertensive drugs. It can also impact lithium levels due to its diuretic properties.

Highly purified stevia extracts are generally considered safe in moderation, but whole-leaf or crude stevia products are not. Pregnant women should consult their healthcare provider before use due to limited conclusive research.

Refined stevia, specifically high-purity steviol glycoside extracts (like Reb-A), is FDA-approved and generally considered safe. Crude stevia, or whole-leaf stevia, is not FDA-approved and lacks sufficient safety data regarding its long-term effects.

Some users have reported experiencing side effects like headaches and dizziness after consuming stevia. This is often associated with high intake or a sensitivity to the sweetener.