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The forum seems to have been somewhat absorbed with discussing bowel habits of late :dazed: so I thought I had better check to see whether there was any science behind our assumptions that increasing fibre, drinking lots of water and consuming figs, prunes etc are the way to counteract constipation.

So here is a systematic review (this is the best way of analysing all the studies done on a particular subject) on the evidence for fibre in treating constipation: It concludes:
Soluble fibre may be of benefit in chronic idiopathic constipation, but data for insoluble fibre are conflicting. More data from high quality RCTs are required before the true efficacy of either fibre type in the treatment of chronic idiopathic constipation is known.

('Chronic idiopathic constipation' just means constipation that has been going on for a while and for which there is no obvious cause).
So, just increasing fibre may not be the answer. If you do want to increase your fibre intake it looks like you should concentrate on soluble fibre, such as oats, chia seeds, pulses (legumes) rather than things like wheat bran, flaxseed etc. This is contrary to what we have generally been told (much like the low fat story, eh?)! Indeed, I found this interesting review of the causes of constipation:, which says:
A search of recent literature, however, reveals that there is a paucity of evidence-based publications that address the etiologic factors of chronic constipation. Much of current writings on the subject may be based primarily on myths handed down from one generation to the next.

This review suggests that the general advice handed out by all doctors (i.e., more fibre, more water, more exercise) only works if the patient has deficiencies in this area, so if you already have plenty of fibre, water and exercise, increasing them will not help. Interestingly, I found a statement in this paper saying
One prospective study showed that Bifidobacterium supplementation can relieve constipation in hypocaloric dieting,95 whereas another prospective trial reported efficacy of Lactobacillus in improving chronic constipation in nursing home residents. However, survival and viability of these probiotic bacteria as consumed in commercial form has yet to be standardized for such treatment to be officially endorsed.

This shows that constipation is perhaps an inevitable consequence of just eating less, but that it might be possible to improve things with probiotics.

Regarding prunes, I found a randomized controlled trial (the best kind of scientific study) looking at prunes vs psyllium husk, which came out in favour of prunes:

Looking at increasing fluid intake, I found mixed results of studies. My general impression is that if you are dehydrated this can worsen constipation which is then improved by drinking more but that if you are adequately hydrated anyway, drinking more may not have an effect on constipation. I did come across one theory that if your drinking water is high in magnesium sulphate (i.e., you live in a hard water area), this could improve constipation and so the water hardness could be a confounding factor in studies examining the influence of water intake on constipation. (Magnesium is a well-known and widely used laxative, and as magnesium has so many other benefits, particularly on sleep, it's the method I use to ensure regularity!).

So, bringing all this together, I think the best approach might be to create your own breakfast cereal with oats, chia seeds and prunes, serve it with natural yoghurt and at the same time ensure you are drinking enough throughout the day. But for me, I'm sticking to my magnesium!

Finally, here's a great page summarising the evidence for different treatments for constipation:
I used to find magnesium worked for me - now it doesn't seem to!
All Bran every time :-)
I love you @Babyfish mwahhh. I was beginning to think I was all alone in my love of the brown cardboard stuff. But no, another Allbran lover!

:lol: :lol: :lol: :lol:
I am addicted to the stuff - it is also my fast day dinner! A massive bowl with hot milk. Yum!
Babyfish wrote: All Bran every time :-)

As I said in my review of the scientific evidence, the benefit of fibre is only if you don't get enough anyway. Which, of course might be the case for people who are dieting!

All Bran is too high in sugar IMHO. Although it contains some soluble fibre, it is not the ideal way of counteracting constipation due to the sugar content. Also, being wheat bran, it's no good for those who are wheat intolerant.
Caroline, does magnesium affect your bowel function? I bought a calcium/magnesium tabs from H&B and about three days later I started getting the runs regularly.... so I stopped taking them and my gut settled down again. Could this be linked - I've been loathe to re-commence them just in case, if I'm honest....
carorees wrote: . But for me, I'm sticking to my magnesium!l

Thank you for the exceelent review - this is something I definitely suffer from and I usually end up drinking senna tea a couple of times a week :bugeyes:

It sounds like you take magnesium supplements to help you with this, do you have a particular type? does it come as a salt eg magnesium sulphate etc or is it pure magnesium? It's definitely worth my trying some :grin:
I should have said thank you to @carorees.
All I can add, is that it works for me - may not be for everyone, so take what I say with a pinch of salt and what Caroline says with a great deal of respect.
@carorees Thank you very much indeed for your post with such valuable information. I have been suffered from constipation for most of my life and have to take senna to get things working. What I have never understood is why this is despite eating a high fibre diet and exercising at least 5 times a week. I have porridge and prunes for breakfast and use a magnesium spray so I wonder is there a better way to take the magnesium?
garnet25 wrote: @carorees Thank you very much indeed for your post with such valuable information. I have been suffered from constipation for most of my life and have to take senna to get things working. What I have never understood is why this is despite eating a high fibre diet and exercising at least 5 times a week. I have porridge and prunes for breakfast and use a magnesium spray so I wonder is there a better way to take the magnesium?

Ditto here except porridge without prunes for breakfast but I add chia seeds, flaxseed meal and other tasty fibery things to my daily diet
Magnesium sulphate (Epsom salts) is the standard way of clearing a patient's gut out prior to surgery! It's very effective! This is because it's not well absorbed, so to get the benefit of magnesium for sleep etc and for preventing constipation you need to try a formula that's better absorbed, like magnesium citrate, or take a mixture. I found some tablets that have a mixture of magnesium compounds which seem ok...not too dramatic an effect on the bowels. Like Domane, I tried a calcium/magnesium mixture which was too powerful for was magnesium hydroxide in that one.
Thank you @carorees I had a conversation with a woman who was doing some decorationg for us who I think was on the primal diet. She reckoned soluble fibre was the answer and insoluble fibre - she called it roughage - caused inflamation of the bowel wall. I personally found some improvement adding wheat bran rather than oat bran to my porridge. As regards hydration I usually find about an hour after having a drink I do a wee of about the same amount - I presume that means I am hydrated and my kidneys are doing their job. It continues to astonish me the stuff I can put in the top end that doesn't seem to want to appear at the other.
This is very useful info, Carorees, and many thanks. I was brought up in North East England with only occasional problems but living in soft water Yorkshire has caused me lots of difficulties, especially when I have dairy products which I now have to avoid as much as possible. I eat lots of fruit and veg and take calcium to supplement the lack of dairy produce but still things could be better.

I read about magnesium helping things along, bought some today and took the first one a couple of hours before reading this thread.


Will report back.
Thanks for the info, Carorees. :like: My problem, according to my GP, comes from one of the tablets that I've been prescribed for something else entirely! She has given me sachets of powder (Movicol), to be mixed with water, which are really salty but do work - eventually! They contain polyethylene glycol, sodium chloride, sodium bicarbonate and potassium chloride - so no wonder they taste so revolting! :frown: It's no wonder I prefer to take senna tablets, as required!
Perhaps I'll try magnesium next time I'm near anywhere likely to sell it. :smile:
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