Primal eating for many people means prioritizing whole foods but not entirely eschewing natural sweeteners in the occasional recipe. We’ve covered the likes of stevia, yacon syrup, and Swerve recently, but what about another popular choice in the growing selection of natural sweetners—monk fruit? What is it, and where does it come from? What are the benefits (not to mention risks) that studies point out? And how do we compare the various formulations next to each other in the supermarket aisle? Let’s break this down.
What Is Monk Fruit?
Known as luo han guo in its native southern China, monk fruit (Siraitia grosvenorii) first found acclaim in the records of 13th century Luo Han Buddhist monks. The monks valued the inherent sweetness of the fruit and made it their mission to cultivate the vines through the centuries. Today, most monk fruit cultivation still takes place in the misty mountains of China’s Guangxi province and a few surrounding areas, where the conditions are just right to grow and harvest the small, orange-sized fruits.
Monk fruit belongs to the cucurbit family, alongside the likes of squash, cucumber and watermelon. Fresh off the vine, the mini melons have a bitter outer rind encasing a sweet edible pulp and seeds. But unless you know someone who’s managed to cultivate monk fruit in their garden, you’re unlikely to ever eat a fresh monk fruit. The flesh degrades quickly, meaning most exported monk fruit has been dried and/or processed to ensure longevity.
Thus, most monk fruit finds its way to American shelves as a concentrated natural sweetener. As always, the nature of that sweetener can vary markedly depending on the way in which it was processed. An average serving of pure monk fruit extract contains virtually no carbs, calories or sugars, deriving almost all of its sweetness from a group of antioxidants called mogrosides, with mogroside V having a sweetness 250 times that of sucrose (table sugar).
To put that sweetness in perspective, most people consider just 1/64 of a teaspoon of monk fruit extract to taste as sweet as a full teaspoon of table sugar.
But in order to get this natural “zero calorie” sweetener, much of the inherent compounds in the fruit are lost. Prior to arriving on supermarket shelves, most “pure” monk fruit sweeteners are treated with a solvent to remove off-flavors, evaporated to remove other sulfurous volatiles, homogenized, and pasteurized. The resulting extract is very different to its original state, slightly undermining its purported status as a natural sweetener.
Other less processed natural monk fruit sweeteners provide a more wholesome version of the original fruit, but with the arguable downside of containing a small amount of glucose and fructose. More carbs also tend to mean fewer mogrosides, and hence a lower relative sweetness.
Monk Fruit’s Nutritional Profile
Contrary to what people might claim, fresh, unprocessed monk fruit is not sugar free – figures vary between cultivar and growing region, but fresh monk fruit is typically one third carbohydrate, composed of a mix of fructose and glucose.
With the extraction of the juice, however, much of those carbs are left behind. At this point, a minimally-processed monk fruit extract sweetener might only contain small amounts of sugars in the form of fructose or glucose, at which point it becomes a low-calorie natural sweetener. A half teaspoon serving of this monk fruit juice powder, for example, is made up of 10% sugar, with the rest of the carbs presumably being composed of mogrosides and other unfermentable sweet-tasting compounds.
At the other end of the scale, pure monk fruit extracts such as this one truly are zero-calorie sweeteners, with no carbs and no sugars. Manufacturers are sometimes hesitant to sell straight monk fruit extract, however, because of the common“off flavors,” choosing instead to mix in small amounts of other sweeteners like erythritol or stevia. It’s not uncommon to find sucrose or dextrose lurking on the ingredients list of so-called natural monk fruit sweeteners, but the amounts would be pretty minimal.
While monk fruit contains several different mogrosides, the key ingredient is generally mogroside V. This is easily the sweetest-tasting of all the compounds in monk fruit, and very conveniently it isn’t metabolized in the same fashion as simple sugars like glucose or fructose. Mogroside V tends to be poorly absorbed within the digestive system. This accounts for the “zero calorie” claims of monk fruit extract products, and spells good news for those looking to satiate their sweet tooth while avoiding calorie loading or blood sugar spikes.
Potential Health Benefits Of Monk Fruit
While the extraction and refining processes remove most of the original natural compounds from fresh monk fruit, research indicates that the mogrosides and other flavonoids that remain can still impact health. Here’s a brief look at some of the benefits (preventative and otherwise) you might enjoy using monk fruit sweeteners.
As Primal folks know, sugar (not fat) is the leading dietary cause of the obesity epidemic. And as the world has ever-so-slowly awakened to the notion that sugar might be doing the most damage, there’s been a push towards sweeteners that don’t elicit the same insulin-meddling, inflammation-elevating, liver-damaging effects as sugar. Preliminary evidence suggests that the mogrosides in monk fruit sweeteners might be just the ticket. A 2012 study showed that total mogrosides extracted from monk fruit “suppressed the increase in body weight, abdominal and epididymal fats weight” in mice placed on a high fat diet (presumably not good fats). Another study published this year once again showed that obese mice fed mogrosides from monk fruit had significantly reduced body and liver weights compared to control mice. It was thought that the mogrosides achieved this anti-obesity effect by “enhancing fat metabolism and antioxidative defenses”.
Obviously, more research is needed to verify these findings, especially in humans. But its a promising start.
Unsurprisingly, there’s been plenty of research into the potential antidiabetic effect of mogrosides found in monk fruit sweeteners. In one study, mogroside extracts from monk fruit administered to diabetic rats significantly eased symptoms and protected against biochemical abnormalities. In another, diabetic rats were fed monk fruit extract for 13 weeks. Those rats fed the monk fruit extract showed improved insulin response, along with reduced blood sugar levels after glucose administration and a reduction in oxidative stress caused by the diabetes. What’s more, the monk fruit group also showed signs of lowered kidney damage, a common symptom of advanced diabetes.
Yet another study showed that both crude monk fruit extract and mogroside V helped to stimulate the secretion of insulin in pancreatic beta cells.
You get the idea. Once again, more studies in humans are needed to make any definitive conclusions.
While studies are very much in their infancy regarding the negative link between the antioxidants in monk fruit and cancer, there’s likely to be more on the horizon. A 2016 study used mogroside IV, extracted from monk fruit, to inhibit the proliferation of both colorectal and throat cancer cells and suppress tumor growth. An earlier study showed that a range of triterpenoids (including several mogrosides) isolated from monk fruit showed “potent inhibitory effects” on Eppstein-Barr Virus-induced tumor growth. This strong anti-carcinogenic effect was further verified by a subsequent study.
A 2011 study indicated that mogrosides administered to mice significantly reduced inflammation by down-regulating pro-inflammatory genes and up-regulating anti-inflammatory genes. That’s a lot of hyphens….
A more recent study demonstrated the ability of mogroside V to lower induced lung inflammation in mice by more than half. From a slightly more tangential perspective, researchers have also shown that monk fruit extracts reduce physical fatigue in mice (allowing them to swim for longer). This anti-fatigue effect is undoubtedly due, at least in part, to monk fruit’s tendency to lower inflammation.
The health-giving powers of monk fruit sweeteners may even extend to immune function. In one study, groups of diabetic mice were fed either low-dose mogrosides, high-dose mogrosides, or a saline control solution over the course of a month. At the end of the trial, both mogroside groups (but particularly the low-dose group) showed significant protection against diabetes-induced immune dysfunction. Interestingly, this immune-bolstering effect was only apparent in immune-suppressed diabetic mice, suggesting it plays an important role in restoring homeostasis in the body.
This pro-immunity effect is further solidified by the fact that certain monk fruit isolates have anti-bacterial properties, and can prevent the growth of common bacterial pathogens like Streptococcus mutans, Porphyromonas gingivalis and Candida albicans.
Are Monk Fruit Sweeteners Safe?
While long-term, multi-year toxicity trials are notably lacking, no trials have yet revealed anything of concern. For what it’s worth, the FDA gave monk fruit products their GRAS seal of approval in 2010, and it’s of some note that monk fruit has been cultivated and eaten since at least the 13th century, albeit at far lower concentrations.
Limited trials in humans haven’t reported any adverse side effects, and a study in mice showed that, even at ridiculously high dosages, no toxic or mutagenic effects were observed. That being said, the use of highly concentrated monk fruit sweeteners is very much in its infancy. Moderation is a safe bet.
Tips For Buying and Using Monk Fruit Sweeteners
Which product you choose will depend on your preference. Those who prefer an entirely non-caloric formulation will want to go with pure monk fruit extract. Or you may prioritize less-processed versions, which might contain a small amount of simple sugars and a little less mogrosides. At the other end of the spectrum, those who don’t particularly like the aftertaste of monk fruit extract might opt for a blended product that also includes the likes of erythritol, xylitol, and/or stevia.
While most people enjoy the taste of monk fruit, it’s not necessarily for everyone. Taste descriptors vary markedly from person to person, with some noting it tastes like caramel or molasses, others more like a sweet licorice. Keep in mind that the more refined the monk fruit sweetener, the blander and sweeter it will taste.
And speaking of sweetness, remember that mogroside V, the key ingredient in most monk fruit sweeteners, is up to 250 times sweeter than sugar, so a little goes a very long way. Most labels provide a sugar substitution guide for recipes.
How you use monk fruit sweeteners will also depend on your taste preferences. Some common uses include:
- baked goods
- sauces and salad dressings
- fruit/vegetable-based drinks
- Asian dishes that call for a dash of sweetness
That’s just the beginning, really. Experiment, and see how it might work for you and your family.
Thanks for stopping by, folks. Have you used monk fruit as a sweetener, or would you consider trying it? Be sure to share your thoughts below.
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