Is Maltodextrin Keto or Not?
What is Maltodextrin?
Maltodextrin is a food additive which is a white polysaccharide powder made from vegetable starches such as rice, corn, wheat, or potato starch. Maltodextrin is used as a filler and a sweetener in many processed foods.
Maltodextrin is classified as a carbohydrate and usually contains less than 20% of sugar (sucrose) by weight. Due to its sugar and starch content, maltodextrin does have a high glycemic index and in larger amounts, maltodextrin could raise your blood sugar levels.
The ketogenic diet is obviously a low-carbohydrate diet and one of the biggest challenges people have while trying to get into ketosis or stay in ketosis is being about to identify those hidden carbohydrates that may knock you out of ketosis.
It’s not always easy to understand what ingredients may put you over your daily carbohydrate allotment. Even as a doctor, I’ve been fooled reading some of the ingredient labels.
Maltodextrin is one of the ingredients that you might not recognize and if you do see it as an ingredient you might wonder if maltodextrin keto or not.
What foods have maltodextrin?
Maltodextrin is in a wide variety of processed foods from protein powders to pastas. It’s also added to soups and salad dressings to help thicken these liquids. But maltodextrin can also be found in “keto” products as well when its used as a sweetener. In fact, maltodextrin is even found in Splenda.
Are there benefits to maltodextrin?
Maltodextrin may help prevent muscle breakdown after resistance exercise when taken as part of a post-workout drink. 1. A 1985 study looked at the effects of 100 grams of carbohydrate on muscle protein balance after weight lifting in 16 subjects. The eight test subjects that drank the 100 grams of carbohydrates as maltodextrin did not show a difference in the rate of muscle synthesis compared to the group that did not drink the carbohydrate drink, there was a significant decrease in muscle breakdown noted in the carbohydrate group.
I’m assuming that these test subjects were on a normal high-carb diet (the study was in 1985) and not a low-carb or ketogenic diet, so it’s hard to say if someone on a ketogenic diet would see a similar decrease in muscle breakdown consuming a similar high carbohydrate post-workout drink.
This group also had significant and measurable increases in their blood glucose and insulin levels after consuming the carbohydrate drink. From a bodybuilding or muscle physique perspective, there’s a benefit to having maltodextrin in a post-workout protein recovery drink since it can decrease the amount of muscle breakdown.
Concerns about maltodextrin
Most maltodextrin in the United States is made from processed genetically-modified corn. If you are concerned about GMO foods in your diet, then look for the “organic” label which should designate that the corn used to make the maltodextrin is not genetically modified.
If you have a gluten or wheat allergy, you can also look at the ingredients list and if the maltodextrin is from processed wheat, the manufacturer is required to list that fact on the nutrition label.
Maltodextrin may impact gut health and gut microbiome. 2 A 2019 research study in mice found that mice feed maltodextrin had an increase in gut inflammation compared to mice fed either animal gelatin or propylene glycol. While we don’t know the long-term impact of changes in gut microbiome in humans, one of the main premise of the ketogenic diet is that it decreases inflammation in the body compared to the typical Standard American Diet.
Because of the highly-processed nature of maltodextrin, the sweetener has a high glycemic index. In fact, the glycemic index of maltodextrin is higher than table sugar. Maltodextrin has a glycemic index between 100 and 105 while table sugar has a glycemic index of about 65. Maltodextrin also has a much higher glycemic load than regular table sugar.
Both the higher glycemic index and glycemic load of maltodextrin can increase blood insulin levels and potentially worsen insulin resistance in susceptible individuals.
Possible side effects from Maltodextrin
The most important side effect from maltodextrin is its effect on raising blood glucose and blood insulin levels due to its high glycemic index.
Because of the impact on higher blood sugar levels, maltodextrin may also:
- Increase insulin resistance (which can lead to Type 2 diabetes)
- Increase triglyceride levels (which are a risk factor for heart disease)
- Negative changes in the microbiome of your gut
- If you have Crohn’s Disease, maltodextrin consumption has been linked to flare-ups of this intestinal disease. 3
- Mice fed maltodextrin over 10 weeks were more likely to develop colitis (inflammation of the colon) due to decreased mucous production 4
Maltodextrin for Sports Performance
There has been a good amount of research on possible exercise performance benefits of maltodextrin, not only on endurance athletes, but also potential benefits for resistance-focused athletes.
Maltodextrin and Marathon Running Performance
Sports drinks and gels consuming maltodextrin may improve exercise performance. A small study of 14 marathon runners published in 2014 found that the runners that consumed sports drinks and gels with approximately 60 grams of maltodextrin were about 10 minutes faster than runners that did not consume the maltodextrin sports drinks and gels during the race. 5 found that test subjects that consumed 100 grams of a maltodextrin drink after leg press exercises had less muscle breakdown than the test subjects that only consumed water with an artificial sweetener.
A more recent study published in 2020 6 didn’t show any benefit in performance when consuming maltodextrin prior to weightlifting as far as measuring leg press performance. This lack of result may have been due to the fact that these athletes were already on a higher carbohydrate diet and had normal muscle glycogen levels before consuming the maltodextrin and the workout.
Maltodextrin and Medium-Chain Triglycerides
Combining maltodextrin with medium-chain triglycerides (MCT) may provide improved fat oxidation during moderate endurance exercise compared to athletes that consumed just maltodextrin during exercise. 7 This study looked at untrained test subjects and measured their change in fat oxidation over 2 weeks when consuming 6 grams of MCTs and 67 grams of carbohydrate as maltodextrin. The group on the MCT and maltodextrin had a significantly higher level of fat oxidation when exercising on a stationary bike at 50% and 70% of VO2max. The study suggests that there may be a benefit to sports drinks or gels with a combination of MCT and maltodextrin.
How does maltodextrin affect ketosis?
Maltodextrin can knock you out of ketosis because of its carbohydrate content that can raise blood glucose levels, and as a result, also raise blood insulin levels as well. As mentioned previously, maltodextrin has a much higher glycemic index and glycemic load compared to table sugar. This higher glycemic index and load means that there is a quicker and higher increase in blood glucose levels after consuming maltodextrin.
Is maltodextrin keto or not?
Maltodextrin is a carbohydrate and in larger amounts it will raise your blood sugar and insulin levels, so maltodextrin is not keto-friendly on a ketogenic diet. However, there may be some benefit to using maltodextrin either during or after long endurance exercise or resistance and weightlifting workouts.
Maltodextrin during exercise may improve running performance and maltodextrin after a workout may decrease muscle damage and breakdown, allowing faster recovery from hard workouts. While not strictly keto, many ultraendurance athletes like Zach Bitter follow the Optimized Fat Metabolism diet where they strategically add carbohydrates like Maltodextrin during their workouts and races for an added boost of energy.
However, I wouldn’t recommend foods with maltodextrin as a normal part of a well-formulated low-carb keto diet.
Best Keto Sweetener Alternatives to Maltodextrin
If you’re on the keto diet do improve your insulin sensitivity and metabolic health, then avoiding a high-glycemic sweetener like maltodextrin would make sense.
If you need a ketogenic-friendly alternative to maltodextrin, then erythritol would be a keto-appropriate sweetener to replace maltodextrin. Erythritol is sold under a variety of brands, but Anthony’s, Whole Earth, Swerve and Nourished are some of the most popular versions of erythritol.
Erythritol is classified as a sugar alcohol and is very low-carb with about 0.25 grams of carbohydrates per serving. Because its a sugar alcohol, there is minimal impact on blood glucose and insulin levels.
In fact, erythritol has a glycemic index of 0!
While erythritol is absorbed in the small intestine, the body does not metabolize erythritol. Almost all of the absorbed erythritol is actually excreted in the urine. Erythritol (like xylitol) also does not promote tooth decay since bacteria in the mouth can not use it as a food source. 8
Other keto-friendly sweeteners
Stevia and Monk fruit are two other keto-friendly sweeteners that do not significantly raise blood sugar levels or affect insulin response.
Truvia is a blended sweetener that combines erythritol and stevia for a more balanced sweetness profile and can also be used in baking.
Want to learn more about the Ketogenic Diet?
Confused on how to track if you are in deep ketosis? Use our glucose-ketone index calculator to see if you are maintaining nutritional ketosis. Read this article if you need to learn more about the Glucose-Ketone Index.
Effect of maltodextrin on muscle recovery and damage
Maltodextrin may also be anti-catabolic, meaning it helps prevent muscle breakdown, especially after exercise. One of the original studies on maltodextrin’s effects on post-exercise muscle recovery in 1985 ((https://journals.physiology.org/doi/full/10.1152/japplphysiol.00333.2003?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org