Welcome to The Fast Diet › The official Fast forums › Body › Benefits and side effects › diarreha on day after fast
This topic contains 143 replies, has 107 voices, and was last updated by cmma01 7 months, 3 weeks ago.
Viewing 50 posts - 1 through 50 (of 149 total)
5 Jun 13
Does anyone else suffer from diarreha the day after fasting. It’s driving me crazy. I have been following this WOL for a couple of months and lost half a stone so am delighted and want to keep going but I bothered by stomach cramps and diarreah without fail the day after I fast as soon as I eat breakfast. Which is a bit embarrassing when I am at work! lol. Is anybody else affected in this way and how do you manage it??
Have you been eating anything different than normal?
I had a bit of trouble with a “celeb” diet last year, turned out to be cottage cheese, which I don’t normally eat.
You might also be taking less fibre than your body is used to, or drinking excessive fluids to stave off hunger pangs.
I always take probiotics(tablet form -not actimel). They don’t do anything for weight loss, but they do keep your gut healthy.
Thanks Deb, I think you could be right about excessive fluids. I do tend to drink alot when I am fasting. Will try probiotics too – do you just get them from the supermarket or do you need to go to chemist?
6 Jun 13
I get mine from Holland & Barrett, Acidophalous chewable, but Superdrug sell Prebio 7, which is great for a starter, also Optibac, which is a 7 day soluble form.
Hope they work for you.
17 Jun 13
I’ve had this trouble too! Really bad cramps and terrible diarrohea as soon as I eat anything after a fast day. I’ve just started taking a probiotic, hoping this will help. I love doing this diet, but tummy issue is really putting me off!Any advice from anyone who has overcome this problem?
28 Jun 13
I’ve come on line especially to see if anyone else has this trouble. I’m sorry for you others but glad it isn’t just me. It is completely uncontrollable; I too get a cramp pain just before. Although I thought I’d got it sussed, today was the third day I’ve been caught outside the house. I’m not eating more fruit or veg than normal on the fast day. I’ll try cutting down on water but I’ve been drinking to stop a headache. I don’t understand the science of it; I can’t fathom why it happens. It takes away one of the ideas of this diet – that on fast days you look forward to the next day. I certainly don’t, not the morning anyway.
Sorry, have no suggestions to help.
This horrible reaction apart I’m like this diet and won’t give it up.
14 Jul 13
I seem to get diarreha soon after breaking my fast. We are skipping meals.on the fast day until.evening.which.suits us best but get diarreha within one hour of eating. Can be quite severe but usually gone by next day. Anyone else experience this?
31 Jul 13
Hey. I’m really glad I’ve found this thread. Today is my first proper fast day and although I ate little yesterday it was still over 500 cal so decided to start today. Anyway I had a slice of toast this morning and had my fast meal this evening, but literally about an hour after eating I had a very embarrassing bowel problem but was luckily home alone!! Is this normal? Did anyone else experience this on their first day? I have been drinking a lot of water however not anymore than I have done in the past and this has never happened before!! Some help and support would be greatly appreciated!!
1 Aug 13
I have the same problem too. In my case the problems seems to be related to milk. If I have a breakfast in the no fast days with milk after hours the problem starts. I’m trying to not assume milk to verify. I suspected in the past to be intolerant to milk, the fasting seems to amplify that.
Hi all, sorry to read about your diarreha problems. I have not had the problem myself during my “fast” days but have googled “diarreha and fasting”. Those with symptoms may find some comments helpful by doing this but a word of caution. Some of the comments may not be based on scientific or medical evidence but may help in your particular case.
Also remember that when this happens your body is likely to be loosing certain nutrients that may need replacing such as body salts. I am not medically trained and my comments are based on personal experiences.
As ever be careful as to what each of you do to solve the problem and if needed seek medical advice from your doctor.
Wow, I hadn’t really made the connection. If I resume normal eating on a Friday morning (usual weekday porridge) I never have any problem, but if I have changed my fasting days and resume normal eating on a Saturday morning (cooked breakfast at local cafe) I often do have a one-off reaction.
Must think about that a bit more, and perhaps experiment with different breakfasts.
Yes, I did. But it settled down after a few weeks and has not returned.
Probably got rather a lot to do with the amount of water I was and still do drink on a fast day.
19 Aug 13
You’ll see above that in June I was having severe problems at the start of the diet. I haven’t had any diarreha problems now for well over a month. Touch wood that problem for me is over.
Diet going very well.
24 Aug 13
I tend to agree with the milk thing. Unfortunately I don’t think that’s the case for me. I have narrowed it down to lack of fiber, too much oil and lack of probiotic. Only by trial and error. Before I started this diet I had this same problem but only after I ate fast food or any food from a restaurant. I ate a lot of fried foods at home but I always used new oils. Little pieces of previous fried foods get stuck to your food as its frying and I tested this by not constantly changing out the oil and indeed I had diarrhea after the meal fried foods in used oil. I had a lack of diarrhea when I ate Greek yogurt for breakfast and took benefiber in my coffee. So that works for me I hope this helps others.
I have only recently started doing this diet but I had the same problems after my first day of fasting. I had horrible cramps before hand. It’s reassuring to see I’m not alone.
26 Aug 13
I have had this problem two fast in a row. I am on my third week and will see what happens on Wednesday after I eat. I found the diarrhea lasts for the whole day. Then I become constipated for about two or three days. I don’t feel really plugged up but it is stressful. Is this a normal side effect of the fasting..
28 Aug 13
I am having diarrhea about an hour after eating the first substantial meal I have the day after fasting. I don’t however have cramps or pain, and it’s just one extended episode.
I think perhaps this has to do with activation of the liver (enzymes?) following consumption of protein and fat; I’ve had this same condition after high-protein meals. I think it’s more intense because of all the water I drink on a fast day.
The time after my second fast day wasn’t as bad as the first. Hopefully this will just diminish over time.
16 Sep 13
Hi I am glad to come across this thread. I started the diet last week. My first day of fasting went absolutely fine no problems whatsoever. On my second day in the evening the bowel problems set in, I was glad I was home alone. I have had the same thing this evening. Luckily I have stocked up on imodium and it seems to have eased quickly. Am I going to get this every fast day? Is due to drinking to many fluids? I usually eat lots of fruit and veg so don’t think its down to that.
Oh god, don’t talk to me about diarrhoea. My fast day yesterday was hell. Guess I need to stock up on immmodium :-\
20 Sep 13
Aniann–I’m not a doctor, but I don’t think you should grab the Immodium. Diarrhea, while unpleasant, is the body’s way of ridding itself of something that’s bothering it. Stopping it up could just cause more problems down the road.
I came to this thread because last night, two hours after breaking my 24-hr fast with a 500-calorie (very healthy calories, too, I might add–lean chicken breast, kale, cucumber and tomato salad, celery and pepper slices with a tbsp of hummus, and quinoa) I had diarrhea come on very suddenly. To be frank, I almost didn’t make it to the bathroom in time! Thank goodness I was in the comfort of my own home and not out and about. It was mystifying. Yesterday was my 11th fast (I have been on it now since Aug. 16) and this is the first time anything like this has ever happened.
My first thought was that I had eaten too much. I didn’t even finish my cucumber and tomato salad because I couldn’t eat any more (I never thought I’d see the day when less than 500 calories would make me full!). I purposely pick foods on fast days that are filling and bulky and that allow me a good variety. I wouldn’t want to blow all of the calories on one item! So I usually get a lot of veggies plus some lean protein.
Anyway, it went away as soon as it came, thankfully, and I’ve had no recurrence. It was strange. I’m glad others have had the same thing happen, so that I know I’m not alone.
Good luck to everyone!
20 Oct 13
I’m glad I’m not alone with this problem. I had my first fast day yesterday and broke my fast this morning. Afterwards I was constipated then fine til after lunch where I went the opposite direction and had to rush to the bathroom after severe cramps. Luckily I was at home! I have put it down to 1 T ice cream and 1 T whipped cream I had after lunch with strawberries. I don’t usually have dairy so thinking it might be dairy intolerance? I’ll try taking a probiotic and removing dairy to see what happens.
I had diarrhea the day after my first fast day but it was only once. Cramping pains and then whoosh!! I expected something, so this wasn’t too bad. I did 2 days in a row though so the body may react differently? Will see how I go next week.
I don’t suffer from diarrhoea so far, but in the past I have had random occurances which I suspect are related to too much fat (chocolate). The symptoms described here with the stomach pain is exactly what my boyfriend experienced severely for a year until he worked out it was an allergy to garlic and onion (and anything in that family) and small hard things like whole grains and small seeds.
Best of luck to all with figuring it out.
I too have been having rapid onset diarrhea after my first meal after fast day. It doesn’t always happen but frequently. First I thought it was the volume of food as I often have a full eggs and bacon and home-fried potatoes that day. Then I thought is was the high carb load and might be a form of “dumping syndrome”. Here is definition from wikipedia:
“Gastric dumping syndrome, or rapid gastric emptying is a condition where ingested foods bypass the stomach too rapidly and enter the small intestine largely undigested. It happens when the small intestine expands too quickly due to the presence of hyperosmolar (having increased osmolarity) contents from the stomach” It leads to sweating, nausea, diarrhea and can happen soon after eating or 1 to 3 hours after. I am not sure it is any one food but a combination of factors like high volume of food and the gut primed to react by the previous day’s fast.
I am going to try eating a smaller breakfast the day after and see if it helps.
22 Oct 13
I did my second fast day today, so will have a smaller breakfast than the other day and take out dairy and see what happens. I hope everyone is having a good week otherwise 🙂
4 Nov 13
I to have had this problem, but not all the time. I usually eat the same meal the day after a fast. It usually kicks in after the end of a fast week. I did wonder if it’s just down to the amount of fat being burned on a fast day that your body has little or no use for. Then when you come off your day and eat a substantial meal the overload then gets moved on? rapidly! No doctor but i have started eating a small meal after the fast and this has helped.
I have read some of your posts here, not all of them – but I still need to say this; please don’t start drinking less because of your diarrhoea! When you have diarrhoea your body loses a lot of fluids on its own so you need to keep replenishing them. Maybe drinking a bouillon to also replenish some salts is the way to go.
My body is used to different eating regimen so I don’t have these problems anymore, but I do remember severe stomach aches when breaking a fast earlier. This is no longer a problem for me however. Maybe it goes away with time, but if it lasts longer than a month I think there must be some other reason… I’m sorry I can’t help you guys any further.
If it happened to me, I’d probably keep a food journal of what I was eating after my fast day and check for any possible food intolerances. I do know that I have a food intolerance to cow protein, so it would happen to me if I ate something with a lot of butter or milk or cow cheese. And then I would also get very tired and have aching joints for a few days. Luckily I haven’t experienced this and I do drink a lot on my fast days.
5 Nov 13
It must’ve been fate that I posted on this forum about not having this problem, and that same night spend an hour on the toilet…
I think in my case it was just my body being a bit shellshocked, I’d done almost a 48 hour fast with just a little bit of chicken and spinach halfway, and then I ate quite a large meal. Same tomorrow (fast day today again, so only eating a little bit tonight) so let’s see what happens then… x)
6 Nov 13
I had sudden diarrhea at the end of my first fast day rather than the next morning as experienced by some other posters here. I drank black coffee / sugar-free hot ribena all day, then had a 85 cal protein shake after my 5pm cardio, then a 500 calorie salad mix in a bap with a side of strawberries, blueberries and clementines at 9pm or so.
Around 9.20pm I had to rush to the toilet and went around 4 times that night!
Other than that, the first day of fasting was surprisingly easy. Hopefully Thursday will be better in regards to the diarrhea!
This is an interesting thread – I’m having a similar problem but someway otherway round: I’m doing complete ADF, which means I don’t eat for 24 hrs (not even a single calory) and eat whatever I like the next day.
I’m having diarrhea quite often but in the morning of the fasting day so after about 12 hrs consumption and a couple hrs. of sleep.
I’m still trying to figure out what’s causing this. I also have choc on my “suspicion-list” since it happens quite often after eating choc late (it’s ok having the choc in the morning or early afternoon).
Also, wheat is a candidate.
It happens two times a month, so not that often but still unpleasent. It started since my switch to ADF in April.
I’ve started a small diarrhea diary (nice word, isn’t it 😉 where I list times and meals as detailed as I can remember them.
Eating too much and too late is a major cause in many cases, I believe – at least in my case!
15 Nov 13
This is the exact forum I was looking for, as I too have just started the diet and had the same reaction the following day. I put it down to eating fatty foods as I had eaten some Doritos and some chocolate. I assumed my body was trying to tell me something like “Don’t give me anymore rubbish”.
I have always been a bit sensitive, particularly to fatty food, so I think the fasting just exacerbates the problem.
I would love a medical explanation.
I think I’ve found out why I had diarrhea. It was odd I was only getting diarrhea on Mondays and not Thursdays for the last two weeks.
I’ve put it down to using the sweetener in my coffee at work on Monday, whereas I’m at home on Thursday with no sweetener. Going to try without sweetener next Monday and see how that goes!
16 Nov 13
I am lucky, no headaches, can sleep. etc. Three weeks ago, I had to flip my schedule, so I couldn’t keep a regular rhythm, and “skipped” some basic functions. I went back to normal hours this week and thought I was going to die today. I had already got the pepto out of the cabinet before I saw the thread. It was so-oo relevant. 😉
10 Jan 14
Glad to see this thread and know I’m not going crazy. Fast for a day, sometimes most of the following day also. I often exercise on the fasting days (ride my bike to and from work 24km each way). The following day within a couple of hours of eating some breakfast and the diarrhea hits me big time. Lasts for the morning and afternoon but by evening my guys have settled down. Sometimes I do the eggs on toast breaky, sometimes a small bowl of porridge and maybe a muffin, but it doesn’t seem to matter what I eat. During the fast all I consume is black coffee, green tea and some packet soups. Perhaps the necessary bacteria is diminished during the fast so that when food suddenly comes in there are not enough of them. As mentioned by others in this thread, probiotics of some kind might be worth a try.
12 Jan 14
I had this after the first fast but had filled up on berries, veg stirfry and Slim rice. I thought it might be the Slim rice, but the Slim pasta I had on the third fast didn’t affect me. I take it it was all the extra fibre I had with the fruit and veg.
19 Jan 14
I have this as well. I fast with just water – not a large amount and sometimes one black coffee – and often have diarrhea soon after eating.
I look on it as cleansing really – or a bored stomach finally getting something to digest! Maybe that’s a bit simplistic?
7 Feb 14
I get stomach cramps and diarrhea the day after fasting. I had to leave work early today because o fit. It’s very painful and inconvenient. I have read through all the posts about this but can’t find anything very scientific to help. I think I will try and contact Dr Michael direct.
Wow. I started the 5:2 diet a couple of weeks ago and twice so far I have had a sudden attack of diarrhoea on an eating day. The first I dismissed as a one off, maybe a bug kind of thing, but today I decided there’s definitely a connection with the alternate fasting and eating. I broke my fast this morning with a protein and soya milk shake, which is what I usually have for breakfast. No problem at that point, but later on had some home made mushroom soup for lunch and then went into town to shop. About 2 hours after eating lunch, suddenly had to find a loo – fast! OMG, so embarrassed. No tummy ache or feeling ill preceeding, just the sudden urge to excrete and then once over, that’s it. Not sure what can be causing it, but I do drink a lot of herbal teas on fast day.
@new woman …home made mushroom soup has a dire effect on me!!
Having said that I sometimes find that on non fast days my digestive system ‘works faster’. I put it down to my system, having got used to fasting, trying to rid itself of whatever I have the cheek to put in it!!!
I do find it worse at weekends if I go a bit overboard with anything containing sugar. But it’s nice to be ‘naughty’ sometimes 😀
18 Feb 14
4 or 5 weeks into this diet now, and I can say that, for me, the problem has not got any better. Every time I break my fast, doesn’t matter what I eat, the same explosive result. It’s so bad I daren’t break my fast unless I am at home for the rest of the day, which restricts my choices of fasting days somewhat.
Today I have eaten 500g Onken Bio yoghurt in the hope of restoring good bacteria, I don’t know if it will help, but worth a try.
On the plus side; I’ve lost 6.5kgs since new year, and I like natural yoghurt 🙂
20 Feb 14
I’ve found this thread because I’ve suffered bouts of diarrhoea about an hour after eating fast day evening meals for at least half of the fast days I’ve completed. (Done 5:2 since 4 weeks before Christmas, then 6:1 until this week, back to 5:2.) Last night was typical – eat Tasmanian salmon and salad – leaves, cucumber, tomato, little bit of avocado – then an hour later – whoosh! I was trying to clean my teeth and get to bed and wondered if I was just going to have to spend the night on the loo… Kept having to put the toothbrush down and go to the loo again… Four visits, then gave in and took Gastrostop in the hope of getting enough sleep to be able to front up to work today. That worked and am fine today.
This has happened enough times to make me look here for some ideas on how to combat it. I want the potential anti cancer and alzheimers benefits. Had 2 separate cancers last year, so want to do what I can to help myself but diarrhoea doesn’t seem healthy?
27 Feb 14
Hello all, I came here today wondering if I’m the only one. Obviously I’m not! As a vegetarian who eats lots and lots of fiber, I am wondering what I should do differently to try to curb this problem. The diarrhea is uncomfortable but is really just in the morning. the real problem is the general “loose,” gassy and crampy feeling in my stomach that lasts for days after a fast. I try to fast on Tuesdays and Thursdays, and it takes me until Saturday or Sunday to feel back to a normal digestive state! I will try more yogurt and probiotics to calm my system down. I wonder what it is about fasting that has my digestive tract so… angry.
4 Mar 14
I am finding probiotic yogurt does seem to help. I went abroad on holiday for a couple of weeks and couldn’t get hold of any, so took probiotic capsules instead and that also seemed to work.
7 Mar 14
Hi – very glad to have found this post, I was on the verge of starting a new one when I spotted this.
I have been doing 5:2 for approx 12 weeks now and lost 11lbs – I’ve never really had any problems with diahorrea whilst being on this WOL but last night I did.
I normally fast Monday and Thursday’s but this week, I was meeting up with a friend for a meal on Thursday night, so decided to fast Monday and Wednesday, with no problems.
I didnt really go overboard with what I was eating yesterday during the day, as I was saving myself for my meal out – I had approx 600-700 calories during the day. I really enjoyed the meal, but I guess in retrospect I did eat a lot – well a lot more than I have been used to over the past 12 weeks – I certainly could have eaten more before I started this way of life.
Anyway, we finished our starters and mains and didnt have room for desert, so asked for the bill and all of a sudden I became very uncomfortable with stomach cramps and sudden urgent feeling. I ignored it and wriggled a bit and managed to subside the feeling, making a mental note to go straight to the loo as soon as I got home.
Anyway, I got home approx 30-40 minutes after this episode and went promptly upstairs, not expecting to have diahorrea, which would have me stuck on the loo for 10 minutes 🙁
As soon as I was done – no more problem, in fact I felt as though a weight had been taken off my mind 🙂 although my stomach does feel a bit ginger today, so being very careful what I eat.
My personal opinion on why it happened to me is that I generally just ate too much in one sitting – I totalled the calories intake for that one meal at approx 1600 calories! Much like others, I think my stomach has got used to smaller portions, so large portions are just out of the question now, which is a positive really and will definitely make me more mindful moving forward.
As I say I have never had any digestive problems with this way of life, prior to last night – in fact, I probably had more digestive problems before I started this way of life, as on a regular basis I would suffer from stomach cramps and pains due to the food I was eating – this way of life is definitely teaching me what is good for my body and what is not so good.
So pleased I found this post, as its nice to know Im not the only one.
@jjm87 – no, you’re not the only one. The same thing happens to me if I eat too much on a non fast day. I just put it down to my stomach rebelling against being ‘overloaded’ as it doesn’t happen on a regular basis – just after a bit of over-indulgence and especially if that over-indulgence has involved a fair bit of sugar.
This WOE definitely teaches us to listen to our bodies.
10 Mar 14
I’m new to this diet – about 4 weeks now… and yesterday (feed following fast day) was sure a test! From about mid-afternoon on I was pretty much housebound, and it lasted all night intermittently.
I believe I read something from Moogie about the unwanted results from eating too richly after a fast – and it seems that is what I experienced. Also – I know that my stomach can be sensitive to dairy. My question is – what is meant by “richly” -do you think it means carb, protein or fat… or just too much at once?
My feed day looked like this:
AM: 150g steak + 2 eggs (enjoyed myself a bit)
SNACK: Lite Latte (non-fat milk)
LUNCH: Cucumber Sandwich (cucumber, cheese slice and ham), no bread
SNACK: 2 pieces of homemade Banana Bread (approx. 250 Kcal total)
DINNER: Bowl of Beef Stew (Meat, Potatoes, assorted Veg)
So – was it the heavy Breakfast, the milk in the coffee (I usually drink mine black, but this was a “treat”), the Banana Bread or that darn stew?
I really know next to nothing about digestion. I’m looking for a place to start making adjustments next feed day as I’d like to avoid the unwanted results…
1 Apr 14
Thank you for asking this question. Mid-morning day, after a fast day, I find myself in your same situation. It’s not a problem, but I’m trying to figure out cause and effect. Perhaps this is a part of the cleansing.
I have the same problem. But when it does happen I will eat half a cup of boiled rice and that fixes me up over the next hour or two. I’ve pondered incorporating rice into my first meal to see if that makes a difference; I will repost when I find out how it affects me.
You must be logged in to reply.
Username or Email:
Track your weight and measurements, BMI and TDEE with our new tracker.
The Fast books are available throughout the world and in many different languages. Buy a copy today.
Michael is touring Australia this September! Here's a link to dates and tickets. Hope to see you there.
Michael Mosley gives an update for 2019, current research in the field and announces a tour starting in February.
Michael looks at the Horizon special, "What's the Right Diet for You" and tells us which diet they say is best for him.
• All featured posts •
in Welcome to The Fast Diet and Exercise forums • updated 4 hours, 21 minutes ago by GdayfromSA
in Weight loss • updated 7 hours ago by symba7
in Weight loss • updated 10 hours, 4 minutes ago by stitchincarol
• All recent topics •
Copyright © 2021 Michael Mosley and Mimi Spencer
Technical questions or problems with the site? Please email our technical contact.