If you’re thinking about starting the Carnivore Diet, you might be a little worried about the lack of fiber. Well, the complete nonexistence of fiber in the diet. The Carnivore diet has zero grams of fiber. And even if you’re doing a strict keto diet, you might not always be consuming the recommended 25-30 grams of daily fiber intake. You certainly won’t be consuming any (whole) grains on a keto diet.
You’ve most likely read articles touting the health benefits of fiber. You’ve seen headlines proclaiming that dietary fiber is beneficial for multiple health conditions. Fiber is supposed to help reduce risk of heart disease, stroke, and colon cancer, improve constipation, and even help with weight loss.
So the question is whether or not you actually you need 25-30 grams of fiber each day.
It is estimated that the average American consumes about 16 grams of fiber a day (1). And that fiber is not likely coming from vegetables. Current recommendations are to aim for 25-30 grams of fiber daily (2).
While it is widely accepted that a high fiber intake improves overall health, there is research showing no benefits of a high fiber diet.
For example, a 2013 study that included over 9,000 people found that increasing fluid intake improved constipation better than increasing fiber intake (3).
Another study found that fiber can “exacerbate abdominal distension, flatulence, constipation, and diarrhea” in patients with functional gastrointestinal disorders (4).
This study showed that advice to increase fiber intake did not improve the mortality rate of men who had recently had a heart attack (5).
A 2005 prospective cohort study that included over 725,000 people, followed for 6 -20 years, found “high dietary fiber intake was not associated with a reduced risk of colorectal cancer” (6).
And finally a smaller 2016 study showed that stopping or reducing fiber intake actually improved constipation (7).
So now what? How much fiber should you consume each day?
The answer is to experiment with your diet. n=1. Try reducing your fiber intake and see how you feel. Maybe you do better with fiber from vegetables than fiber from grains. You might tolerate cooked vegetables better than raw vegetables. If you do struggle with constipation, try increasing your fluid intake. And always talk to your doctor before making any major changes.