Lastly, one of the advertised benefits of IMO is possible prebiotic activity. Prebiotics are critical, as they feed the beneficial bacteria in our digestive system, specifically in the large intestine. These bacteria have several amazing functions, such as lowering body fat, improving insulin sensitivity, and lowering depression. Two “gold standard” prebiotics in the industry are inulin and fructooligosaccharides (FOS). Inulin and FOS are non-digestible carbohydrates that robustly increase beneficial bacteria. The challenge, however, is that both inulin and FOS, due to their rapid digestibility by intestinal bacteria, result in low gastric tolerance, and, ultimately, gastric distress. Additionally, inulin and FOS, when added to protein bars or other goods, may degrade over time into individual sugar units. Regardless, one study comparing inulin to IMOs, found that the prebiotic activity in inulin is 14 times greater than that of IMOs.[4] This is logical because, as you recall from above, approximately 70% to 90% of IMOs are digested. As such, only a small portion of these prebiotic fibers make it to the large intestine, in which two out of three studies have demonstrated that this small portion may indeed have some prebiotic effects.
Low in carbs and high in fiber, lupini beans (aka lupin beans) are perfect for those on keto who are looking for a high-protein, high-fiber snack. Never heard of them? This yellow legume is hot on the heels of the edamame and fava bean as an on-trend nibble for the health-conscious consumer.  One cup of cooked lupini beans contains 4.6 grams of fiber—about 19% of the recommended daily value. However, ready-to-eat branded lupini bean snacks often contain even more. “I've noticed that the amount of carbs/fiber can vary greatly between lupini bean brands,” says Yule. “To make sure that you are choosing a food that is keto-friendly, be sure to check the label.”
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.
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.
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.
Even so, keto followers may experience a rise in LDL cholesterol, sometimes called “bad” cholesterol because too much of it can lead to a buildup of plaque in the arteries, which can increase the risk of heart disease. And that’s where fiber can help. However, many high-fiber foods, like beans, fruits, vegetables, nuts, seeds, and whole grains, are also high in carbs, so they're limited on the keto diet.
As observed by the graphs above, in contrast to the IMOs in which blood glucose rapidly increased to 125 mg/dL, SCF did not elicit any blood glucose response.[9] In addition, while insulin was elevated during the IMO condition, it actually tended to go down in the SCF condition! Despite the results from the blood glucose and insulin responses, the breath hydrogen assay will distinguish which is a “true fiber.” Our data below clearly indicates that SCF indeed passes into the large intestine, as indicated by the large breath hydrogen response. In stark contrast, IMOs do not.
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.
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Seeds are another high-fiber food that you can eat on keto, but only occasionally to stay in ketosis. Full seeds, ground seeds and seed butters will help to increase your fiber intake and minimize keto flu symptoms like constipation. Plus, they supply important nutrients, including essential fatty acids and protein, and are known to support cardiovascular health.

Psyllium husk is a type of fiber commonly used as a gentle, bulk-forming laxative. With no net carbs and a whopping 7 grams of fiber per two tablespoon serving, ground psyllium is an easy way to increase fiber intake on the keto diet. “It works great as a binding agent in recipes,” Yule says. “Just make sure to consume it with plenty of water, coconut water, or juice to avoid dehydration.” Add a tablespoon to your beverage, and you’re good to go.


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.

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.


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I’ve been on the Keto zone diet for over 2 months and finally feel energy and a sense of fullness. I have logged purposely the meals you suggested in your book however when I test to see how I’m fairing in fat burning with the ketones sticks I come up in the middle. I tried to adjust here and there to see if my percentages are aligning to the 70-15-15 as you suggest but it still comes up in the middle. In other words I’m average in the fat burning process. Is this just stubbornness on my body’s part?I’m slowly loosing weight but slowly. I exercise but that hasn’t changed anything. Thanks for your help!
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!
Psyllium husk is a type of fiber commonly used as a gentle, bulk-forming laxative. With no net carbs and a whopping 7 grams of fiber per two tablespoon serving, ground psyllium is an easy way to increase fiber intake on the keto diet. “It works great as a binding agent in recipes,” Yule says. “Just make sure to consume it with plenty of water, coconut water, or juice to avoid dehydration.” Add a tablespoon to your beverage, and you’re good to go.
Quick and Easy 10 minutes and 3 ingredients only Jellied Keto Cranberry Sauce Recipe made with Brown Sugar, you will make day after day. This Homemade, Gluten-Free, Low Carb and Grain Free Healthy Sugar-Free Cranberry Sauce Recipe goes perfectly not only on your Thanksgiving table but is a great addition to any meat stews, breakfast jam or filling for your Keto Crepes.
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