Rebaudioside A vs. Stevia: An Overview
Stevia (Stevia rebaudiana) is a plant from South America, recognized for its sweet leaves. Its sweetness comes from steviol glycosides. Rebaudioside A (Reb A) is one of many steviol glycosides within the stevia leaf and is favored for its taste.
Commercial stevia products are made from a refined extract, often Reb A. This process separates the palatable glycosides from the bitter ones, ensuring a consistent flavor.
The Relationship: Plant vs. Compound
The distinction can be understood by comparing an orange and orange juice. The orange is the whole fruit, while the juice is a refined product. Similarly, the Stevia rebaudiana plant has many compounds, and Reb A is a purified extract.
- Stevia (The Plant and Its Crude Extracts): The whole or dried stevia leaf has been used for centuries, especially in Paraguay and Brazil, for sweetening drinks. The whole leaf contains a complex mixture of steviol glycosides, which can cause a bitter aftertaste. The FDA has not approved the whole stevia leaf as a food additive due to a lack of data.
- Rebaudioside A (The Refined Extract): This steviol glycoside is extracted from the stevia leaf and highly purified, often to 95% or more. This removes bitter components, leaving an intense sweetness, up to 300 times sweeter than sugar. Highly purified Reb A and other steviol glycosides have been approved by the FDA as a food additive.
Comparison Table: Reb A vs. Stevia Leaf
| Feature | Rebaudioside A (Reb A) | Stevia Leaf (Crude Extract) |
|---|---|---|
| Source | Highly purified extract from the Stevia rebaudiana plant. | The raw, dried, or crude extract from the Stevia rebaudiana plant. |
| Purity | High purity, typically 95% or greater steviol glycoside content. | Lower purity, containing a mix of different steviol glycosides and other compounds. |
| Taste Profile | Characterized by a clean, sweet taste with minimal to no bitter aftertaste. | Can have a licorice-like or bitter aftertaste due to unpurified compounds. |
| Sweetness Intensity | Approximately 200–300 times sweeter than sugar. | Varies, but generally less potent and consistent than the purified extract. |
| Regulatory Status | Approved as a food additive (GRAS) by the FDA when highly purified. | Not approved as a food additive by the FDA; can only be sold as a dietary supplement. |
| Commercial Use | Used in most widely available stevia-based products, like Truvia and PureVia. | Primarily used for home use (e.g., adding a raw leaf to tea). |
The Importance of Purity and Regulation
The FDA's distinction between the crude stevia leaf and highly-purified steviol glycoside extracts, like Reb A, is important for consumer safety. The purification process ensures the final product is free from potentially harmful compounds found in the whole leaf, which have not been studied for long-term health effects.
The FDA's GRAS status for high-purity steviol glycosides means they are safe for food use. This provides consumer confidence in the safety of commercial stevia sweeteners containing Reb A.
Considerations for Consumers
Consumers should be aware of the difference between the whole leaf and the purified extract when choosing a stevia product. Most sweeteners labeled 'stevia' contain high-purity Reb A or other approved steviol glycosides. Some commercial products include other ingredients like erythritol or dextrose to improve the taste. Check the ingredients list.
Growing stevia at home and using the leaves is an option, though the taste may not be as consistent as the refined extracts. For consistent sweetness, high-purity Reb A is standard.
Conclusion: A Clear Distinction
Rebaudioside A is not the same as stevia. Reb A is a purified sweet compound from the stevia plant. Stevia can refer to the plant itself, its leaves, or the refined extract. Commercial stevia products use Reb A for a clean taste profile and consistent sweetness after purification. The distinction helps consumers understand the ingredients in their sugar-free products. For more information on the safety of steviol glycosides, review the findings of the Joint FAO/WHO Expert Committee on Food Additives (JECFA).
