I never did find a polite way to describe the anus, the rectum, the colon, the intestines etc… so let’s stick with the more appropriate medical terminologies when referring to the opposite end of the digestive tract from where the food goes in
While discussing this topic, all the above will apply.
I suspect most people reading this will, at sometime, have been told about the need to consume more fibre in their diet – for ‘obvious’ (we are told) motility and health reasons. My gastroenterologist even told me it was good for diarrhea, as it would mop up all the liquid!
So like good obedient children we follow the advice of our elders and consume the RDA of fibre in our diets – don’t we?
The RDAs for fiber for healthy adults are 38gm/day for males 19-50 years old and 25 gm/day for females 19-50 years old. The RDA for fiber decreases with age. Males age 51 years and older need 30 gm/day; females age 51 years and older need 21 mg/day. The requirement for fiber varies somewhat among individuals. The average American eats about 15 grams of fiber a day – too little to meet the RDA. source
Have you ever questioned this advice? Where does it come from and has it ever been proven – to be of value to your good health. Are there opposing views and any science to back those up?
…The father of the fibre hypothesis: Dr Denis Burkitt
Dr. Denis Burkitt was the first researcher to connect a high fibre diet with better health. Studying rural communities in Africa, he noticed that eating a traditional diet resulted in healthier stools and bowel movements in contrast to those living in cities and consuming a western diet. Those eating local produce had extremely low incidences of diabetes, irritable bowel syndrome, constipation, diverticular disease, colon cancer or heart disease compared to those consuming a Western diet. After looking at many factors, Dr Burkitt concluded the high amount of fibre in traditional diets was necessary for maintaining good health.
Has the Fibre Hypothesis been proven accurate? Not according to some health advocates I have been following. Quite the opposite in fact:
For decades, fiber has been touted as an essential component of a healthy diet. The supposed benefits of a high-fiber diet have been drilled into us through recommendations by our doctors, government, and the food industry alike, yet many of these health claims have not been proven by research.
In fact, many studies have demonstrated that excess intake of fiber may actually be harmful, particularly for gut health.
The majority of the research supporting the benefits of dietary fiber come from epidemiological studies that link the consumption of fiber-rich fruits and vegetables with a lowered risk of certain diseases such as obesity, heart disease and cancer, particularly colon cancer. (1) Yet when tested in the lab, controlled intervention trials that simply add fiber supplements to an otherwise consistent diet have not shown these protective effects. source
When it comes to the detrimental effects of fibre in the diet there are quite a few published papers showing the ANTI value of consuming these substances.
Point in fact, did you know that high-fibre wheat-bran is associated with a significant increase in colorectal cancer?
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/10770980
This study evaluated the effect of wheat-bran fibre in patients who had had one or more histologically confirmed colorectal adenomas removed. The study, which lasted three years, included 1,303 patients, aged 40 to 80 years, who were given wheat-bran fibre supplementation of either:
(i) 13.5 grams a day (high-fibre group).
(ii) 2 grams a day (low-fibre group).
The study found:
(a) The high-fibre group had a 5.8% increased risk of death compared to the low-fibre group.
(b) The high-fibre group had a 9.2% increased risk of any cancer compared to the low-fibre group.
(c) The high-fibre group had a 215% increased risk of colorectal cancer compared to the low-fibre group.
(d) The number of patients who reported gastrointestinal effects was significantly higher in the high-fibre group than in the low-fibre group for all effects except constipation.
Reported gastrointestinal effects:
(i) Nausea: 69% higher in the high-fibre group.
(ii) Abdominal Pain: 60% higher in the high-fibre group.
(iii) Diarrhea: 82% higher in the high-fibre group.
(iv) Constipation: 5% lower in the high-fibre group.
(v) Intestinal gas: 46% higher in the high-fibre group.
(vi) Abdominal bloating: 66% higher in the high-fibre group.
OK so that is one rather negative published study, what about others?
Who has not been told, or heard about in the media – of the benefits of eating bread that is fibre rich in wheat? But did you know that consumption of fibre-rich wheat bread results in iron deficiency .
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15349738
The objective of the study was to measure the effects of long-term consumption of the recommended intake of fibre-rich wheat bread on the iron status of young healthy women with adequate iron stores. The study lasted for four months and included 41 healthy women, average age 24.8 years, who were provided daily with 300 grams of fibre-rich wheat bread, prepared (i) with or (ii) without phytase (an enzyme that reduces the phytic acid content in food) as a supplement to their habitual diet.
After four months, the study found:
(a) Levels of ferritin were significantly reduced in all women by an average of 27%. (Low ferritin levels lead to anaemia).
(b) Levels of haemoglobin were significantly reduced in all women by an average of 1.5%. (When a person has a low haemoglobin level, they may feel weak, tired, dizzy or cold).
I could go on, but think you may get the idea that there is certainly no consensus when it comes to things of science. If anyone tells you, that you can obtain a consensus in science they really do not know what they are talking about. You get consensus in matters political… that is where health matters and decisions are made for the ‘good’ of the general population, but scientists should, could and do continue research and discussions which do not always agree with the status quo!
Let me see if I can spell this out in a simple way.
Scientists develop a THEORY
From that theory they then do scientific experiments to TEST the theory
From the tests they then produce a paper which claims PROOF of the theory.
THEORY – TEST – PROOF… wonderful and that is that????? NO WAY
Other scientists must attempt to duplicate what the first one is claiming as PROOF. Many times over, these other scientist cannot duplicate, and they will make a counter claim that the first scientist has it WRONG.
So NO CONCENSUS.
As my husband would say in card playing terms, scientific proof trumps consensus.
However once a government advisory or agency gets a hold of things
they want to impose on society – who cares about scientific proof –
because the committee can agree and that is all that matters –
that is what they called consensus!
When Dr. Denis Burkett formed his hypothesis that fibre was the factor prevalent in the diets of the African tribal people he was observing, making them healthier than the towns people, he completely neglected to take into account the fact that the tribal people were eating NO processed foods, and that their diets were predominantly low in carbohydrates and higher in natural saturated fats.
Should we send Dr. Burkett back to the tribes of Africa today (if that was possible and they had not been influenced by modern society) with the instructions to observe and calculate the fat, protein, carbohydrate content of these peoples diet versus the Tribal People who had migrated to the towns and cities, I seriously doubt that fibre would come out on top as the item that fostered healthy bowel movements and lack of illness.
I feel certain that once the nutrient content was shown to contain no processed foods, liquid vegetable oils, sugars, toxins, colours and additives, it could be theorized, tested and PROVEN that it is due to the non influx of modern diet on these tribal people that kept them free of modern day disease such as diabetes, irritable bowel syndrome, constipation, diverticular disease, colon cancer and heart disease.
It had not much if anything to do with fibre!
A couple of things before I sign off. Do I consume fibre in my diet? YES in the vegetables I eat. I do not supplement with fibre products nor do I consume grains.
I also want to thank David Evans for his wonderful resource blog where, if you are interested you can find and research many health related topics.
For those still scratching their rectums and wondering if
I made this all up, here are a few more
published studies to ponder on.
Higher carbohydrate and fibre consumption leads to increased rates of breast cancer. This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/19056583
The dangers of a high fibre diet. This paper can be accessed at: http://ard.bmj.com/content/57/11/641.full
Fibre rich diet results in zinc, copper and magnesium deficiencies. This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/8829129?dopt=Abstract
High-fibre supplement (psyllium) linked to colon cancer risk. This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/11073017
High fibre diets may lead to metabolic syndrome. This paper can be accessed at: http://jcem.endojournals.org/cgi/content/abstract/90/5/2618