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Colonoscopy Prep: Low fiber diet


I was diagnosed with Crohn's a little over a year ago and I’m scheduled to have a
Colonoscopy (2nd since the diagnosis, 3rd in my lifetime).

I am wondering if anybody has any experience with doing a low fiber diet (instead of clear liquid diet) for Colonoscopy prep?

Here is my situation:

I’ve done a lot of research and there appears to be many very respected hospitals which use low fiber diet prep, but none of them are in my area.

I talked to my doctor and despite his policy of requiring a clear liquid diet, he is willing to let me try a low fiber diet but he said everyone he’s seen who has tried it had too much residue in their bowels and he couldn’t see well enough with the scope.

I don’t know how to square this with the fact many respected hospitals use the low fiber diet and even the Society of American Gastrointestinal Endoscopy says it’s proven no less effective than the clear liquid diet.

My doc said his patients who tried the low fiber diet “did it on their own”, not under any guidance from him, so it’s unknown exactly what they did.

I absolutely hate the clear liquid diet (I’ve done it twice now) and my understanding from my doctor is he’s going to want me to get Colonoscopies every year for awhile to monitor things, so ideally I’d like to find an alternative.

If anyone has tried the low fiber diet, I’d really appreciate hearing anything about it you that you are willing to share, especially whether the outcome was successful (i.e. the doc could see what he needed to see).

Thanks much!


my little penguin

Staff member
Low fiber plus prep (ducolax /miralax or mag citrate )?
Here is the thing
Despite clear diet being less than ideal
Do you want your Gi to be able to “see your entire large colon “?
You have a disease that requires very close monitoring
Including visual /biopsies
Food will be in the digestive tract as waste if you eat anything and that will block the view
Even if it’s low fiber.
Even colored Gatorade or milk (no fiber ) can cloud things

Ds has had 7-8 scopes by now as a child from age 7 on
You can do low fiber a few days prior to prep day
or some times they do miralax daily increasing doses the week before so less traumatic on prep day

Each prep is different
Some use ducolax /miralax (easiest used in kids )
Other go lytely which is horrid
Mag citrate not much better

Good luck
San Diego
I hate the clear liquid diet prep too, but I'd rather do the clear prep once and have a good result than have to repeat the low fiber/residue multiple times when the colonoscopies don't turn out so well.

It's really important for the proper assessment, and hence proper treatment, of your disease that the GI have an unobstructed and unclouded view of the lining of your gut. To achieve that I'm willing to put up with the clear liquid diet once every year or two.
Thank you both for your replies.

I do want to make sure the GI can see what he needs to see, I just didn't want to the do clear liquid diet again if it wasn't necessary. Since nobody has posted saying they've done a low fiber only prep and had good results, I will play it safe and stick with the clear liquid diet my GI recommends.

Thanks again.


Staff member
New York, USA
To me, having the clear liquid diet for 1 day is well worth getting clear results from a scope. Yes it can be annoying, especially it seems that ALL the commercials on TV that day are for FOOD lol....

Hope all goes well!
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