Stevia
Derived from the leaves of a South American plant, which is a part of the sunflower family, the active sweet compounds, called stevia glyosides, are extracted and refined. Liquid Stevia is one of the most popular keto sweeteners.
Pros
- Zero carbs and zero calories
- Does not raise insulin levels or blood sugar
- Very sweet taste
- Safe to use
Cons
- Very sweet but doesn't taste like sugar
- Cannot be swapped equally into existing recipes
Sweetness: 200 times sweeter than sugar
Erythritol
Made from fermented corn or cornstarch, erythritol is a sugar alcohol that occurs naturally in small quantities in fruits and fungi like grapes, melons and mushrooms. Marketed under the brand name, Swerve, among others, this is one of the most popular keto sweeteners today.
Pros
- Negligible amount of calories and carbs
- Does not raise blood sugar or insulin levels
- Passes into the urine without being used by the body
- Easy to use to replace real sugar in recipes.
- May prevent dental plaque and cavities
Cons
- Doesn’t have the same mouthfeel as sugar
- Can cause bloating, gas and diarrhea in some people (though not as much as other sugar alcohols).
Sweetness: About 70% as sweet as table sugar.
Monk fruit
Monk fruit is a relatively new sugar substitute. Although the fruit in whole form contains fructose and sucrose, monk fruit’s intense sweetness is provided by non-caloric compounds called mogrosides, which can replace sugar.
Pros
- Does not raise blood sugar or insulin levels
- Has a better taste profile than stevia. In fact, it is often mixed with stevia to reduce cost and blunt stevia’s aftertaste
- Can be mixed with erythritol to reduce expense and improve use in cooking.
- Doesn’t cause digestive upset
- Very sweet, so a little goes a long way.
Cons
- Expensive.
- Often mixed with other “fillers” like inulin, prebiotic fibres and other undeclared ingredients
Sweetness: 150-200 times as sweet as sugar.
Synthetic sweeteners
Synthetic sweeteners, often referred to as artificial sweeteners, are created in laboratories from chemicals and other substances.
Aspartame
Aspartame is the most widely used sugar substitute in the US and arguably the most controversial. In addition to being used in many “diet” foods and beverages, it’s sold as a sweetener under the brand name Equal (and formerly as NutraSweet).
Pure aspartame contains no calories or carbs and hasn’t been shown to raise blood sugar or insulin levels in most studies. Aspartame packets, however, contain nearly 1 gram of carb each from dextrose.
Sweetness: 200 times as sweet as sugar
Saccharin
Discovered in 1878, saccharin is by far the oldest synthetic sweetener. It is marketed under the brand name Sweet ‘n Low.
While pure saccharin contains no calories or carbs, packets do contain dextrose. It’s well known for its bitter aftertaste.
Sweetness: 300 times as sweet as sugar
Sucralose
Sucralose is the sweetener found in Splenda, which has been marketed as the sugar substitute that “tastes like sugar because it’s made from sugar.” This is true; the sucrose (white sugar) molecule has been modified so that it no longer contains carbs or calories – and is much, much sweeter.
Like the other artificial sweeteners mentioned, packets of Splenda contain dextrose, which does contribute calories and carbs.
Like other synthetic sweeteners, research on sucralose is mixed. Most studies have found that it doesn’t have any impact on blood sugar or insulin levels when consumed alone, while others suggest it may increase blood sugar and insulin levels when consumed with carbs.
Sweetness: 600 times as sweet as sugar