Bowel movements are one of those things that are so individual that it’s impossible to get clear what’s really going on. If one is eating plant foods, one probably needs fibre to help clear it from the digestive tract. As Jason Fung says, “Carbs are the poison, and fibre is the antidote.” Carnivores and many on keto often find that fibre is either not necessary or is even detrimental to their bowel. As Dr. Fung adds, “If you’re not taking the poison, why would you need the antidote?”
Now, many people have this idea that it is necessary to move our bowel every day. It is not. The idea of “regularity” is an advertising term, devised by laxative makers to sell their product. (It’s like the advice to eat five servings of fruit a day, which was made up by Dole, Chiquita, and other fruit growers and importers.)
Many people who embark on a ketogenic diet, and especially a carnivore diet, cannot wrap their heads around the fact that less-frequent bowel movements are healthy and normal for their circumstances, because the idea of “regualrity” has been drummed into our heads for so long. Constipation is defined as difficulty moving the bowel, having to strain, or experiencing pain while eliminating. Not needing a bowel movement for a few days is not constipation, if there is no difficulty eliminating.
Moreover, all those studies of fibre and bowel health were done on a high-carb population, and there is no reason to expect that fibre would benefit someone eating a zero-carb/carnivore diet. Many forum members find that instead of helping their irritable bowel, Crohn’s disease, or what have you, fibre actually makes the symptoms worse. Eating a diet (keto or carnivore) that includes minimal or no fibre actually allows their intestines to heal, and the β-hydroxybutyrate generated helps promote the healing.
So these are some of the considerations to take in mind. If you want daily bowel movements, for whatever reason, then you may want to consume foods with fibre in them, but it remains true that there is no essential carbohydrate, not even fibre.