How is your Fiber February going dear reader? Are you maxing that intake and making sure your digestive track is at full capacity? Maybe that’s why some people use the washroom after eating, things start coming out to make space of new things?
Fiber is obviously part of a healthy diet. Let’s look at what the Harvard School of Public Health has to say
Fiber can’t be digested, and it passes through the body undigested. Excellent. It’s great for you because it comes in, and then it leaves, nothing happened.
I’m not going to gloss over the sentence that says it regulates body’s use of sugars, keeps hunger and sugar in check. The easy answer: fiber fills your stomach so you feel full, thus less hungry. Regulates blood sugar because it is not doing anything. 100g of carbs vs 70g carbs and 30g fiber, means fewer carbs being metabolized.
And done, let’s go to bed.
If it were that easy… The article from Harvard School of Public Health lists numerous and wonderful benefits and provides studies for MOST (not all) benefits. These benefits come in the form of reduced risk for: 1) Heart Disease; 2) Type 2 diabetes; 3) Diverticular Disease; 4) Fiber and Constipation (no studies cited); 5) Colon Cancer; and 6) Breast Cancer
Let’s tackle all of these, I’ll do the work for you. Let’s start with the weak spot, 4) Fiber and Constipation. Also please note that no studies were cited.
“Fiber seems to relieve and prevent constipation” and that’s all we get. We’re going to have to find out how such claim came to be, or how this belief is commonplace.
A lead article “Health Benefits of dietary fiber” [1] explains a lot about, well the health benefits of dietary fiber. A lot of fascinating stuff, but we’ll jump to our area of interest. I will mention that this article does promote fiber use because it reduces risk of: coronary heart disease, stroke, hypertension, diabetes, obesity, and certain gastro intestinal disorders. All topics worthy of discussions, however we are focusing on gastrointestinal disorders today, specifically constipation. Let’s look at their opening paragraph:
“Strong theoretical arguments” and “Clinical trial Data and expert opinions are also lacking for these very common disorders”. Fascinating. This article was published in 2009, so this is recent. We have two distinct messages. Harvard School of Public Health saying it “seems to relieve and prevent constipation.” And this study saying that Clinical Data and Expert opinion is lacking. It is fair to say that the paper is referring to multiple disorders and not constipation specifically, although it is spelled out in the group of disorders that lack data and opinion.
I want to highlight the paper’s mention of diverticulitis before heading to constipation, I get distracted by all these sexy topics. You know the feel. It is also point number #3, mentioned a few paragraphs above. Diverticulitis is when diverticula (bulging pouches in the colon) become inflamed, and infected. This can cause severe abdominal pain, fever, nausea and change in bowel habits. The paper states that the existing “limited data to support the use of fiber supplements are inconclusive”, and that inulin fibers may play a role in reducing inflammation of colon diverticuli “but no clinical trials have yet been reported”. In short, fiber can’t do anything about diverticulitis, but the study is trying to spin it in a positive light – is the author’s bias coming out? Perhaps see screenshot below and let me know
This is the paragraph that references diverticulitis. The limited data and inconclusive results mean that we can’t take a stance on fiber and diverticulitis. Yet, we should feel compelled to recommend a “generous intake of dietary fiber”.
Regarding constipation, there is something that troubles me, and I don’t know how to best present it to you. There is a contradiction.
Constipation:
The author uses consumer behavior as support of fiber “Wheat bran, high fiber cereals are widely used by consumers, which represents common knowledge of their beneficial effects”. So, because people consume it for its health benefits, the benefits are true. I want to visit three paragraphs above:
The author states that wheat bran often increases symptoms of abdominal pain or discomfort, bloating, and diarrhea and/or constipation. A study is cited too. However, I just highlighted the author saying that wheat bran is widely used by consumers as a source for dietary fiber and the beneficial benefits from it. There’s no point in dwelling on this, wheat bran helps constipation, and worsens symptoms including constipation. Very clear cut.
In one of the studies cited by this review paper “Constipation in the Elderly”[2], I came across an interesting table. I recreated it in excel, but it’s true to the original. It lists out types of laxatives, and potential adverse effects. I invite you to have a look. A lot going on, with many different types of laxatives. The least adverse sounding are the emollients and stool softeners, the other ones do not sound pleasant. There’s also mention of enemas, something that has picked up popularity in recent years. It’s out of scope but may be worth visiting it. On to my boy Dr. Paul Mason, in a YouTube video “From Fibre to the microbiome: low carb gut health” he talked about a great study that contradicted popular belief on fiber. This study came from the World Journal of Gastroenterology, “Stopping and reducing dietary fiber intake reduces constipation and its associated symptoms”[3]. As the title states, constipation and symptoms associated with it can be effectively reduced by stopping or lowering dietary fiber.
Kok-Sun Ho et al selected a group of 63 people with idiopathic constipation, (idiopathic meaning not knowing the cause), and they were put on a no fiber diet for 2 weeks, after those two weeks, they were told to continue with no fiber or as little fiber in the diet. Additionally, all 63 patients were already in a high fiber diet. After the two weeks, there was one follow up at 1 month and 6 months.
After the 6 months, 41 patients had continued the no fiber diet, 16 moved to a reduced fiber diet, and 6 patients returned to the high fiber diet, they returned to high fiber for various reasons including being vegetarian, religious, or personal reasons.
The results: the 41 patients who had completely stopped fiber intake, their bowel frequency increased from 3.75 days to 1 day. The 16 patients who were on reduced fiber diet, 12 had daily movement, the other ones ranged from 2-6 days. The patients who were on the high fiber diet, there was no change in frequency of bowel movement, 6.83 days.
Here is the table of symptoms at beginning and after 6 months:
The table above is truly fascinating and should be an eye opener. Let’s look at the symptoms: anal bleeding, constipation, bloatedness, strain in bowel opening, and abdominal pain. 31/63 patients had anal bleeding at the start, 63/63 were constipated, 33/63 were experiencing bloating, 63/63 were straining, and 13/63 were having abdominal pain.
As we move to the following column, the high dietary fiber group, people were still reporting all the symptoms being tracked. It’s important to note that 6/6 still were constipated, 6/6 still had bloating, 6/6 still were straining. If we move to the next group, the reduced fiber group, 12/16 were still constipated, but fewer people were reporting bloatedness, abdominal pain and bleeding. The last, and best column of this study was that 0/41 reported anal bleeding, 0/43 reported constipation, 0/43 reported bloating, 0/43 reported straining, 0/43 reported abdominal pain. All symptoms, gone.
A 100% improvement for the group of people that had completely removed fiber from their diet. This is beyond noteworthy, the results are jaw dropping and in complete contradiction to the commonly held view of fiber helping constipation. Remember when I highlighted above that it was common knowledge that fiber provided health benefits and helped constipation?
I would also like to talk about the analogy that Dr. Paul Mason and Ho KS et al use regarding to constipation. “Constipation is analogous to cars in traffic congestion”, and if you want to get rid of the congestion or slow-moving traffic, you decrease the number of cars and quickly move them out. Adding more cars makes the congestion worse. This applies to patients with constipation, as fiber is undigestible, it adds to the fecal bulk volume, and thus makes it even more difficult to evacuate. Ideally, you want thinner, and smaller pieces so that things move out quickly and painlessly.
To recap, no fiber, no symptoms, more frequent bowel movement.
In the end, we must have a look at the complete landscape and try to understand what is most relevant and important to us. Common knowledge would lead us to believe fiber is the solution, unfortunately it doesn’t resolve symptoms. I’m not here to convince you that fiber should be eliminated, but I do think it is worth considering reducing fiber intake, because that led to reduced symptoms.
I’ll address the other points about fiber, which may be true or otherwise. But your attention is not infinite.
Be better fueled by being Butterfueled
[1] (James W Anderson 1, 2009) James W Anderson 1, P. B. (2009). Health benefits of dietary fiber. Nutrition reviews, 188–205. [2] (Schaefer, 1998) Schaefer, D. C. (1998). Constipation in the elderly. American family physician, 907–914. [3] (Kok-Sun Ho, 2012) Kok-Sun Ho, C. Y.-C. (2012). Stopping or reducing dietary fiber intake reduces. World Journal of Gastroenterology, 4593–4596.
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