Only 20-30 grams of carbs are allowed per day on the ketogenic diet. Since sugar is composed of 100% of carbohydrates, it is entirely off-limits. So does that mean all sweeteners are excluded on keto?
No, you just have to substitute sugar with a healthier option.
But how do you know which sweeteners are healthy and which are not? Let’s break down what sugars are and how natural sweeteners, like allulose, might be the best choice on the ketogenic diet.
What is Allulose?
Allulose is a unique sugar with the same chemical formula as fructose. Because the body doesn’t metabolize it, it does not raise blood sugar or insulin levels and provides minimal calories.
Allulose is also known as D-psicose. It is classified as a “rare sugar” because it naturally exists in only a few foods. Wheat, figs, and raisins all contain it.
The same with glucose and fructose, allulose is a monosaccharide or single sugar. Conversely, table sugar, also known as sucrose, is a disaccharide made of glucose and fructose linked together.
Allulose has the same chemical formula as fructose but is arrayed differently. This variation in structure prevents your body from processing allulose the way it processes fructose.
Although 70–84% of allulose you consume is assimilated into your blood, it is excreted in the urine unused.
It’s believed to resist fermentation by your gut bacteria, minimizing the likelihood of bloating, gas, or other digestive problems.
And here’s some good news for people who have diabetes or are watching their blood sugar — it does not raise blood sugar or insulin levels.
Allulose also contributes only 0.2–0.4 calories per gram, or about 1/10 the calories of table sugar.
Besides, early research suggests that allulose has anti-inflammatory properties. And it may also help prevent obesity and reduce the risk of chronic disease.
Although small amounts of this rare sugar are found in some foods, manufacturers have recently used enzymes to transform fructose into allulose.
The taste and texture have been described as identical to table sugar. It is about 70% as sweet as sugar, similar to erythritol’s sweetness, another popular sweetener.
Recently, Allulose has gained traction amongst health-conscious individuals.
Allulose is a natural, rare sugar that was found in wheat almost 70 years ago. It is also present in small quantities in various dry fruits like jackfruit, figs, and raisins.
The sweetness of allulose is nearly 70% that of sucrose (white sugar), and it’s texture, taste, and baking ability is akin to traditional sugar.
Is Allulose Safe?
Allulose appears to be a safe sweetener.
It has been added to the listing of foods generally recognized as safe (GRAS) by the US Food and Drug Administration. However, it is not yet approved to be sold in Europe.
Studies in allulose-fed rats lasting within three and 18 months have shown no toxicity or other health-related problems. In one research, rats were fed about 1/2 gram of allulose per pound (0.45 kg) of body weight for 18 months. By the end of the study, adverse effects were minimal and comparable in both the allulose and control groups.
It’s worth stating that this was a huge dose. For reference, a similar amount for an adult weighing 150 pounds (68 kg) would be about 83 grams per day — more than 1/3 cup.
More realistic doses of 5–15 grams (1–3 teaspoons) per day for up to 12 weeks weren’t associated with any adverse effects in human studies.
Allulose seems safe and is unlikely to cause health problems when consumed in moderation. However, as with any food, individual sensitivities are always a probability.
It Helps Boosts Fat Loss
Research in obese rats recommends that allulose may also help boost fat loss. This involves unhealthy belly fat, also known as visceral fat, which is strongly linked to heart disease and other health problems.
In one research, obese rats were fed a standard or high-fat diet that held supplements of either allulose, sucrose, or erythritol for eight weeks.
It’s important to note that erythritol also provides virtually no calories and does not raise blood sugar or insulin levels.
Nonetheless, allulose had more benefits than erythritol. The rats given allulose achieved less belly fat than the rats fed erythritol or sucrose.
In another study, rats were fed a high-sugar intake with either 5% cellulose fiber or 5% allulose. The allulose group burned significantly more calories and fat overnight and got far less fat than the cellulose-fed rats.
Because allulose is such a unique sweetener, its effects on weight and fat loss in humans aren’t known because they haven’t been studied yet.
But based on the verified studies on people with lower blood sugar and insulin levels, it appears that talking allulose may help with weight loss.
High-quality studies in humans are needed before any results can be made.
Helps Control Blood Sugar
Allulose may turn out to be an excellent tool for managing diabetes.
Several animal studies have found that it lowers blood sugar, increases insulin sensitivity, and decreases type 2 diabetes risk. That’s because allulose helps protect insulin-producing beta cells of the pancreas.
In research comparing obese rats treated with allulose to rats given water or glucose, the allulose group had improved beta-cell function. Allulose-treated rates also showed better blood sugar response and less belly fat gain than the other groups.
Early study also suggests that allulose may have beneficial effects on blood sugar regulation in humans.
A controlled study provided 20 healthy, young adults either 5–7.5 grams of allulose with 75 grams of the sugar maltodextrin or just maltodextrin on its own.
The group that took allulose had lower blood sugar and insulin levels than the group that took maltodextrin alone.
In another study, 26 adults ate a meal alone or with 5 grams of allulose. Some people were healthy, while others had prediabetes.
After the meal, their blood sugar was measured every 30 minutes for two hours. The researchers found that participants who consumed allulose had lower blood sugar levels at 30 and 60 minutes.
Although these studies are small and more research is needed, the evidence is encouraging.
It Protects You Against Fatty Liver
Studies in rats and mice have found that allulose seems to reduce fat storage in the liver in addition to stopping weight gain.
More commonly known as fatty liver, Hepatic steatosis is strongly linked to insulin resistance and type 2 diabetes.
In one research, diabetic mice were given either allulose, glucose, fructose, or no sugar.
The liver fat in the allulose mice was reduced by 38% compared to mice given no sugar. The allulose mice also encountered less weight gain and lower blood sugar levels than the other groups.
Simultaneously, as allulose may support fat loss in the liver and body, it may also protect against muscle loss.
In a 15-week study of critically obese mice, allulose significantly decreased liver and belly fat, yet prevented the lean mass loss.
Although these results are promising, liver health effects have yet to be tested in controlled human studies.
Why is Allulose Beneficial for the Keto Diet?
For an uncomplicated sugar, allulose is as keto as it gets.
It improves fat oxidation, lowers your blood sugar, may improve your insulin sensitivity, and could even result in weight loss. Plus, allulose is also highly improbable to kick you out of ketosis, unlike other sugars like fructose.
Because your body only consumes a tenth to a twentieth of the calories compared to regular sugar, most of the downsides of eating sugar don’t apply.
That said, any sweet treat or rewarding yourself with food can perpetuate addictive eating patterns. It doesn’t matter if you are using sugar substitutes.
If you’re starting a keto diet, the best strategy is to go a few months without treats to reset your preferences, then enjoy them occasionally.
Once you get to a place where you can possess a healthy relationship with sweet-tasting foods, allulose keto treats are an excellent choice.
The following are a few critical benefits of allulose that has kept it in high demand among keto dieters:
- Allulose is as sweet as sucrose but has 90% fewer calories.
- It has an extremely low glycemic index (meaning it doesn’t spike the blood glucose level after its consumption). It is not metabolized like regular sugar, but rather it is directly absorbed by the small intestine and is eliminated through urine.
- It is a natural, unrefined sugar.
- It is not sugar alcohol and is unlikely to cause gastric distress when consumed in moderation.
- Taste-wise, there isn’t much contrast between allulose and sugar. It has a clean and sweet taste, and the texture is also similar to sugar.
- It is vegan-friendly and gluten-free.
The paleo diet includes eating vegetables, fruits, nuts, roots, meat, and organ meats and excludes any highly processed foods.
People doing a paleo diet can eat allulose, but only if they consume it from natural, unprocessed food.
Dried fruits, brown sugar, and maple syrup hold allulose.
The keto diet is very low in carbohydrates, moderate in protein, and very high in fat. Allulose is a carbohydrate, but it does not produce calories or raise blood glucose than sucrose and is keto compatible.
How to use allulose
Allulose is not as sweet as sugar. People substituting sugar with allulose may need to use more to achieve the same sweetness as table sugar.
The FDA has allowed the use of allulose in:
- selected bakery products, such as sweet rolls, cakes, and pastries
- nonalcoholic beverages
- chewing gum
- confections and frostings
- frozen dairy desserts, such as ice cream, soft serve, and sorbet
- yogurt and frozen yogurt
- salad dressings
- pudding and fillings
- hard and soft candies
- jams and jellies
- sweet sauces and syrups
- fat-based cream
- medical foods
Possible Risk of Allulose
Research suggests that allulose does not create any toxic effects. People who have consumed high quantities have reported bloating, abdominal pain, diarrhea, decreased appetite, and problems related to gas and abdominal sounds.
If you consume too much allulose, you might get nauseous or have diarrhea. The maximum amount you can consume is 0.4 grams per kilogram of bodyweight. That’s about 27 grams, or approximately two tablespoons, for a 150-pound person at a sitting.
Sugar alternatives like allulose can have irregular effects on gut bacteria. The regular upper limit to avoid gastrointestinal side effects is 0.9 grams per kilogram of body weight or 61 grams per day for a 150-pound person.
Unlike artificial sweeteners like Splenda and sugar alcohols like xylitol, there hasn’t been any research on allulose’s impact on the microbiome.
While there’s nothing to suggest it’s harmful, you may want to pay extra attention to how your body responds. Moreso, if you’re prone to gut issues, bloating, or related problems.
If you’re on the ketogenic diet, low to moderate sweetener doses are much unlikely to kick you out of ketosis.
That’s because your body absorbs and eliminates allulose without ever metabolizing it as sugar. It also seems to enhance fat oxidation and decrease carbohydrate oxidation, both of which are beneficial for ketosis.
However, the best way to know for sure is to test your ketone levels after eating it.
Should You Use Allulose?
Allulose seems to produce a taste and texture remarkably similar to sugar while providing minimal calories.
Although there are only a few high-quality human studies on the effects of allulose, it seems to be safe when consumed in moderation.
However, more studies in humans are on the way. Several studies are either recruiting, underway, or have been completed but not yet published.
At this time, allulose isn’t generally available, aside from being used in certain snack bars by a brand called Quest Nutrition.
Quest Hero Bars each hold about 12 grams of allulose, and Quest Beyond Cereal Bars contain about 7 grams. These amounts are similar to the doses used in studies.
Granulated allulose can also be bought online, but it is quite expensive. For instance, allulose sold under the All-You-Lose brand costs about twice as much as erythritol on Amazon.com.
Until there is high-quality research confirming its health benefits, it’s probably best to use allulose in moderation. You can also use it with less expensive sweeteners.
Where can I Buy Allulose?
Allulose is found in tiny quantities in jackfruit, figs, and raisins. Hence, it can be difficult to extra.
In 1994, it was first produced on a large scale, but its production cost was very high. In 2018, corn production and later from sugar beets began, lowering the cost and making its availability more widespread.
Allulose is currently available in food products like Quest Hero Bars, but it has recently become essential commodities. You can find it in stores like Target and Whole Foods and online retailers like Amazon.
When starting the ketogenic diet, people find it difficult to cut back on sugar, and total avoidance is next to impossible for many.
Artificial sweeteners are industrial products and may cause health issues in the long run.
Health-conscious people and followers of the keto diet avoid carbs and monitor calories strictly. For them, allulose is a blessing.
Allulose tastes the same as refined sugar and has no bitter after-taste. Plus, the texture is similar to sugar granules.
Replacing sugar will allulose when you get a sweet craving that may help you stay in ketosis.
- Rare Sugar Syrup Containing d-Allulose but Not High-Fructose Corn Syrup Maintains Glucose Tolerance and Insulin Sensitivity Partly via Hepatic Glucokinase Translocation in Wistar Rats
- Rare sugar D-psicose improves insulin sensitivity and glucose tolerance in type 2 diabetes Otsuka Long-Evans Tokushima Fatty (OLETF) rats