One of the most common disaccharides (two monosaccharides joined together) is maltose. Maltose is generated when two glucose molecules are linked to one another by an α-1,4 chemical bond (1st carbon is bound to the 4th carbon, making it easily digestible). The type of bond involved in saccharide linkage is critical, as it determines its ability to become hydrolyzed by the enzymes we described above. As such, the α-1,4 chemical bond, as listed in the above example (maltose), has the ability to become hydrolyzed (broken down).

One of the first studies to examine IMO syrups[2] had six subjects consume 25 grams of IMO syrup. These researchers found that glucose levels increased from 109 mg/dL pre-ingestion to a peak of 136 mg/dL 30 min post-ingestion. Additionally, insulin rose to nearly parallel levels with that of glucose from 4.8 μU/mL pre-ingestion to nearly 32 μU/mL at 30 min post-ingestion. These values clearly indicate that some digestion is occurring. Furthermore, these researchers found that IMO was about 83% as digestible as maltose under resting conditions and about 69% as digestible after the exercise period. Taken together, this suggests that a large majority of the carbohydrate in the IMO syrup was, in fact, digested, absorbed, and metabolized.

A close relative of maltose is a molecule known as isomaltose (typically found in items such as beer and honey). The biggest difference between maltose and isomaltose is that isomaltose is joined together by an α-1,6 chemical bond, rather than an α-1,4 chemical bond. Scientists suspected that by adding a certain enzyme (transglucosidase) to high maltose syrup, they could change the bonds from α-1,4 to α-1,6, thereby making it more resistant to being broken down by the enzymes, as described above, when compared to maltose. Again, while this sounds excellent in theory, it is not necessarily what happens in our bodies. In fact, isomaltose (and thus, IMO syrups used in some of these products) is broken down by certain enzymes on the brush border of the small intestine.[2] Though the α-1,6 bond breaks down slower compared to the α-1,4 bond, these IMO syrups, which often use a blend of di-and oligosaccharides, ultimately metabolize into small amounts of glucose and maltose[2] and thus should be viewed as a slow digesting carbohydrate rather than a true fiber.
Taken together, the above studies prompt the question: What is the prebiotic activity of SCF? If it is a true fiber, per our definitions above, then SCF should have a beneficial effect on gut microbiome bacteria. A study performed in 24 adolescents noted an increase in beneficial bacteria (e.g., Bacteroides, Butyricicoccus, Oscillibacter, and Dialister). Furthermore, this was correlated with an increase in calcium absorption upon the consumption of 12 grams of SCF per day for three weeks.[7][8] An additional study, which administered 8, 14, and 21 grams of SCF over 14 days, found that good bacteria (e.g., Bifidobacteria) increased and peaked at 8 grams per day. This value is nearly identical to inulin, which is considered the “gold standard.” Despite its nearly parallel effects to inulin at 8 grams/day, research has demonstrated that SCF is 3-4 times more tolerable than inulin due to its slower rate of digestibility by the gut bacteria. In fact, 26 grams of SCF barely increased GI symptoms relative to a placebo!
The increased awareness regarding the importance of fiber, in addition to its distinct metabolic effects, has resulted in a surge of companies switching to an alternative fiber known as soluble corn fiber (SCF). Interestingly, SCF has been available on the US market since 2007 and is used in foods and beverages across the Americas, Europe, and Southeast Asia. SCF is produced through an extensive process: corn syrup is exposed to a suite of enzymes for at least 48 hours, some of which are found in the brush border of your small intestine, as well as the pancreas.[5] Notably, a large majority of the corn syrup contains easily digestible carbohydrates; however, a small portion is, in fact, not digestible. At the end of this enzymatic exposure, a stream of digestion-resistant carbohydrates remains and is subsequently filtered several times. The resulting product is a “true fiber” that contains a mixture of α-1,6, α-1,4, α-1,2, and α-1,3 glucosidic linkages, which, as mentioned above, contribute to its low digestibility.
It can be hard to eat at a restaurant and understanding what everything is made out of. One of the most basic things you can do is stick to the basics. Most people on the Keto diet don’t eat bread, pasta, or rice…easy enough. Of course, staying away from items that are heavy in sugar in carbs is also a good idea. Most people can look at a traditional dish and gauge whether something has a lot of carbs or not.
The increased awareness regarding the importance of fiber, in addition to its distinct metabolic effects, has resulted in a surge of companies switching to an alternative fiber known as soluble corn fiber (SCF). Interestingly, SCF has been available on the US market since 2007 and is used in foods and beverages across the Americas, Europe, and Southeast Asia. SCF is produced through an extensive process: corn syrup is exposed to a suite of enzymes for at least 48 hours, some of which are found in the brush border of your small intestine, as well as the pancreas.[5] Notably, a large majority of the corn syrup contains easily digestible carbohydrates; however, a small portion is, in fact, not digestible. At the end of this enzymatic exposure, a stream of digestion-resistant carbohydrates remains and is subsequently filtered several times. The resulting product is a “true fiber” that contains a mixture of α-1,6, α-1,4, α-1,2, and α-1,3 glucosidic linkages, which, as mentioned above, contribute to its low digestibility.
In contrast insoluble fiber, which does not dissolve in water, is inert to digestive enzymes in your upper gastrointestinal tract. While some forms of insoluble fiber (like resistant starch) can ferment in your colon, most insoluble fiber moves through your digestive system relatively unchanged, absorbing water as it goes, eventually adding bulk to your stool and easing your bowel movements.

Skimping on fiber isn’t good for your digestive health, as it feeds the good bacteria in your GI tract, something that benefits you beyond adequate bowel movements. “The digestive tract is where your body’s second brain is, and it’s home to the majority of your immune system,” says Elia. “If you’re following keto, it should be one of your biggest priorities to make sure you get adequate fiber to keep your gut healthy and happy,” she adds. And, she notes, high-fat diets slow digestion and decrease GI motility, so it’s especially important to get enough.


We’ve all seen it on food labels: “Only 2 net carbs” or “Low net carbs.” But what does this truly mean? What are net carbs, and why does it matter? Are all net carbs created equal, or are we stretching those claims a bit too much? After reading through this article, I think you will agree that there is a pressing need to educate on the precise definition of net carbs, and what exactly constitutes a true fiber.
In contrast insoluble fiber, which does not dissolve in water, is inert to digestive enzymes in your upper gastrointestinal tract. While some forms of insoluble fiber (like resistant starch) can ferment in your colon, most insoluble fiber moves through your digestive system relatively unchanged, absorbing water as it goes, eventually adding bulk to your stool and easing your bowel movements.
Not all the extra ingredients are keto friendly. Some of the dressing mixes are high in carbs as well as some of the extra ingredients such as tortilla strips and croutons. Depending upon how many carbs you eat in a day you may want to avoid those mixes, or at least remove some of the ingredients, and stick with the mixes that only contain salad greens.
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