You’re probably aware that going on a keto diet means cutting out sugar. But what about natural sweeteners?
It turns out that even more natural sweeteners like maple syrup and honey will spike your blood sugar and keep you out of ketosis — so is there any way to bust sugar cravings while sticking to your diet?
Fortunately, there are natural, plant-based sweeteners available to sweeten your coffee, tea, or dessert. And of all these sweeteners, stevia may be the healthiest.
In this article, you’ll learn how stevia works, if stevia is keto-friendly, and how stevia extract compares to other sweeteners on the market like sugar alcohols. Read on.
Hundreds of years ago, the natives of South America discovered a magical shrub in the jungle. The leaves had an incredibly sweet taste, and made for a pleasurable chew[*].
Decades later, in 1905, this shrub was classified as Stevia rebaudiana. The extract from this plant’s leaves would, in time, become known as stevia.
Today, people all over the world use stevia as a zero-calorie sweetener — and the US Food and Drug Administration (FDA) has classified high-purity stevia extracts under the title GRAS (generally recognized as safe)[*].
Pure stevia extract contains high levels of steviol glycosides — compounds responsible for both the sweetness and health benefits of stevia. Due to steviol glycosides, stevia is 200-300 times sweeter than the equivalent dose of table sugar[*].
Extracting glycosides from the stevia plant looks something like this:
- Dry stevia leaves
- Heat water
- Steep leaves in the hot water
- Filter out particles
- Extract the concentrate
- Let it dry
Compared to sugar production, stevia production requires 64% less carbon and 95% less water[*].
So, stevia isn’t just better for your blood sugar — it’s better for the planet. But stevia is mostly known for its effects on your health.
The stevia plant contains several steviol glycoside compounds that lend stevia its sweetening power. These include[*]:
- Rebaudioside A
- Rebaudioside C
A small amount of stevioside or rebaudioside A goes a long way. Despite having no calories, pound for pound they’re much sweeter than sugar.
One common concern with non-caloric sweeteners — stevia included — is that they can trick your body into a glycemic response, causing a spike in blood sugar. However, this isn’t the case with stevia.
In fact, supplementation with stevia extract has been shown to improve the blood sugar response, making stevia supplementation a promising therapy for diabetes[*]. More on that later.
Another concern is that sweeteners like stevia can trigger cravings. Luckily, there’s solid science addressing that concern as well.
In a well-designed 2010 study, researchers compared the health effects of a pre-meal snack sweetened with one of three sweeteners: sucrose (sugar), aspartame (artificial sweetener), or stevia (plant-based sweetener)[*]. Other than the snack, participants could eat as many calories as they liked.
The results were interesting. People fed aspartame or stevia ate fewer total calories than the sugar group. They didn’t overeat to compensate for the caloric shortfall.
But wait, aspartame? Based on these results, aspartame seems like a viable sugar substitute.
Consider the fact, however, that consuming one diet soda per day (often sweetened with aspartame) has been linked to a 36% higher risk of metabolic syndrome and a 67% higher risk of type 2 diabetes[*].
Lastly, you might be wondering: does the intense sweetness of steviol glycosides kick you out of ketosis? There’s no direct research to answer this question, but there is science showing that[*]:
- Stevia lowers blood sugar
- Stevia improves insulin response
Since ketosis is governed by blood sugar and insulin, it follows that these metabolic improvements would likely enhance, not prevent, the production of ketones.
The benefits of stevia, however, go well beyond the maintenance of ketosis.
Stevia is more than just a zero-calorie sweetener. By all indications, stevia extract has some medicinal properties too.
These properties derive from those glycosides. One such glycoside, called stevioside, is highly-researched for its antidiabetic, hypoglycemic (blood sugar lowering), and antioxidant properties[*]. And the others offer some impressive benefits as well.
#1 Stevia May Improve Diabetes
Type 2 diabetes is a metabolic disorder that involves high blood sugar, high insulin, high blood pressure, and obesity. Due, in part, to high-sugar diets, rates of diabetes in America are rising at alarming rates[*].
Recall the study in which participants were fed pre-meal sweetened snacks[*]. After the meal, compared to those eating a sugar-sweetened snack, the stevia group had lower blood sugar and lower insulin levels.
The post-meal insulin improvement, in fact, was unique to the stevia group.
Stevia mediates insulin-secretion in an intelligent way. When blood sugar gets too high, stevioside tells beta cells in the pancreas to release insulin, then insulin gets blood sugar out of your blood and into your cells.
But when blood sugar is low, stevioside does not have this insulin-stimulating effect[*]. This safety mechanism prevents dangerously low blood sugar, known as hypoglycemia.
Bottom line: Stevia lowers blood sugar and improves the insulin response, both necessary to improve diabetes.
#2 Stevia Lowers Inflammation
Tumor necrosis factor alpha (TNFα) is an inflammatory, immune-signaling particle found mostly in fat tissue. High levels of TNFα have been linked to most chronic diseases: heart disease, Alzheimer’s, cancer, diabetes, you name it[*].
In diabetics, TNFα decreases insulin sensitivity by reducing the activity of GLUT 4 transporters — tasked with moving glucose safely out of your blood — in muscle and liver cells[*]. Reduced GLUT 4 activity leads to insulin resistance, which is a short hop from type 2 diabetes.
Stevia may help. Specifically, stevioside lowers TNFα, reduces inflammation in fat tissue, and increases insulin sensitivity[*].
Stevioside also reduces circulating levels of interleukin 6 (IL6) and interleukin 10 (IL10) — two inflammatory cytokines that, along with TNFα, are linked to accelerated aging.
Bottom line: Stevia lowers inflammation by down-regulating inflammatory factors.
#3 Stevia Is an Antioxidant
As you hum through life, your body generates compounds called reactive oxygen species (ROS) as a normal byproduct of metabolism.
At low levels, ROS are necessary signaling molecules. Too many ROS, however, increase disease risk and accelerate aging[*].
Fortunately, your body makes internal antioxidants like glutathione to mitigate the damage of too many ROS. But often you need extra ROS support, and that’s where stevia may help.
Stevia contains high concentrations of phenols — plant-based antioxidant compounds that reduce oxidative stress.
Some researchers believe that these phenols are responsible for the antidiabetic effects of stevia you learned about earlier[*].
Bottom line: Even in small amounts, stevia contains an impressive amount of antioxidants.
#4 Stevia May Improve Blood Pressure
In one randomized controlled trial, Chinese adults with high blood pressure were given 500 milligrams stevioside powder three times a day for two years.
At the end of the trial, the stevioside group had significantly lower blood pressure than the placebo group[*].
The dose, however, was very high — and lower doses don’t appear to have this antihypertensive effect[*].
Bottom line: High doses of stevia may lower blood pressure, but normal everyday doses probably won’t.
#5 Stevia For Oral Health
Eating stevia is not the only way to benefit from this medicinal plant. You can also use it for oral health.
In one six month trial, a mouthwash made with stevia had significant antiplaque and antigingivitis effects in Indian schoolchildren[*].
Bottom line: Stevia as part of a mouthwash may help fight against plaque and gingivitis.
#6 Stevia For Liver Health
Diabetes often causes ROS-driven oxidative damage in the liver[*]. This peroxidation of organ tissue can lead to liver dysfunction, and represents a common, yet serious, diabetic complication.
In one 2013 study, stevia-fed rats showed a 30% decrease in liver peroxidation compared to control groups[*]. It’s not clear if this result applies to humans, but it’s certainly promising.
Bottom line: Stevia may help mitigate oxidative damage in your liver.
As you learned earlier, stevia extract is generally recognized as safe (GRAS) by the FDA.
In fact, stevia has been thoroughly studied in both humans and animal models. Reviewing over 200 of these studies, the Joint FAO/WHO Expert Committee on Food Additives (JECFA) set an Acceptable Daily Intake (ADI) for high-purity stevia extract at 4 milligrams per kilogram body weight[*].
For reference, the ADI is the daily dose of a substance unlikely to cause harm over the course of a human life. To reach stevia’s maximum ADI, a 150 pound woman would need to consume about 40 tabletop packets per day, every day, for the rest of her life.
In other words, stevia is nontoxic and safe for human consumption, even at relatively high doses. Many health experts agree.
“I consider [stevia] safer than aspartame, saccharin, and sucralose and have seen no compelling evidence that stevia poses a threat to human health,” writes natural health expert Dr. Andrew Weil. “I’ve grown it myself at my home near Tucson, Arizona”[*].
Functional medicine clinician and author Chris Kresser has a similar stance.
“The majority of the evidence,” writes Kresser, “indicates that stevia, used in reasonable quantities, is a harmless (and possibly beneficial) natural sweetener”[*].
Side Effects of Stevia
There are two potential side effects of stevia worth noting.
The other side effect? Some people report mild GI distress.
To minimize the chance of this side effect, and to maximize the benefits of stevia consumption, make sure you consume high-purity steviol glycoside extract. And make sure it’s just the extract.
The truth is, many products come with added sugar alcohols like maltodextrin or dextrose — compounds that negate stevia’s benefits and carry undesirable side effects.
The ketogenic diet is a low-carb high-fat diet that can shift your metabolism into a fat-burning state called ketosis. In ketosis, your cells use less glucose and burn more fat, which is ideal for weight loss.
Two interdependent physiological states signal your body to enter ketosis[*]:
- Low blood glucose levels (low blood sugar)
- Low insulin levels
The goal of the keto diet is to simultaneously promote both these states. That’s why keto is low-carb — to keep blood sugar and insulin low.
So then. Does stevia promote ketosis?
There isn’t direct, experimental data to answer this question, but based on stevia’s metabolic effects, the answer is: Yes, almost certainly.
When choosing a stevia product, look for high-purity stevia extract standardized to at least 95% glycosides. That’s the level of purity approved by the FDA[*].
Other forms of stevia — such as crude stevia extracts and stevia leaves — should be approached with caution, as they aren’t subject to regulatory scrutiny.
Stevia extract typically comes in powdered, granulated, or liquid form (liquid stevia). Make sure the product is 100% stevia, and doesn’t contain additional sugars, sugar alcohols, fillers, or artificial flavors.
Stevia isn’t the only sugar-free sweetener on the market. There’s also aspartame, sucralose (Splenda), xylitol, maltitol, sorbitol, erythritol, and monk fruit — to name a few.
Stevia vs. Artificial Sweeteners
When it comes to artificial sweeteners like aspartame and sucralose, cancer concerns — based on one unreplicated rat study — are likely overblown[*]. However, consider the following:
- Drinking diet soda has been linked to diabetes and heart disease[*][*]
- Consuming artificial sweeteners is correlated with preterm delivery[*]
- Artificial sweeteners may trick your body into storing fat[*]
Bottom line? Stevia is safer and healthier than artificial sweeteners.
Stevia vs. Sugar Alcohols
Sugar alcohols have become a popular low-carb sweetener. And while most of them are ok in small amounts, there are some side effects to be aware of.
For example, sugar alcohols — also known as polyols — are not absorbed in the gut and often cause gas, bloating, and other digestive issues[*][*]. This problem is most apparent with xylitol, sorbitol, and maltitol — though erythritol may cause problems as well.
Bottom line: Sugar alcohols are healthier than artificial sweeteners, but they carry more side effects (and fewer benefits) than stevia.
Stevia Vs. Monk Fruit
Monk fruit is similar to stevia. Used for hundreds of years in China, this keto sweetener is:
- 200 times sweeter than sugar
- A potent antioxidant
- Low glycemic index (doesn’t raise blood sugar)[*]
The FDA has not yet approved monk fruit extract, but — based on public communications — they seem unconcerned with its safety profile[*].
Stevia on Keto
Like sugar, stevia comes from a plant. Unlike sugar, however, stevia lowers blood glucose levels, improves insulin function, cleans up ROS, and pulls the brakes on inflammation.
For these reasons, stevia is a valuable tool in your keto toolbox.
That’s right — since stevia lowers blood sugar and insulin, it likely promotes a ketogenic, fat-burning state.
Stevia is inexpensive, safe, and widely available. Best of all, it satisfies your sweet tooth without derailing your diet.
In other words, you can have your stevia cake and eat it too.