Intermittent fasting is a powerful way to give your digestive system a well deserved break, allowing the body’s natural repair and protection processes to work more effectively. This can be particularly helpful if you’re feeling unwell, overwhelmed, inflamed or simply exhausted from constant digestion.
For people with IBS, intermittent fasting can be a game changer. It helps reduce digestive load, calm symptoms and support overall gut health when done gently and sensibly.
This is not about restriction or punishment. It is about rest, rhythm and giving the gut time to recover.
Why resting your digestive system matters
Digestion is one of the most energy demanding processes in the body. Every time you eat, multiple organs are involved in breaking down food, absorbing nutrients and eliminating waste.
When digestion is constantly switched on through frequent meals, late night eating or grazing, the gut rarely gets time to rest. For someone with IBS, this can worsen symptoms such as bloating, cramps, constipation, diarrhoea and discomfort.
Giving the digestive system regular breaks allows the gut to complete digestion fully, reduce irritation and support repair of the gut lining. Many people also notice improvements in energy, focus and overall wellbeing.
Overnight fasting and circadian rhythms
Every night while you sleep, your body is busy repairing, renewing and resetting for the day ahead. This process is closely linked to circadian rhythms, the body’s internal clock that regulates sleep, hormones and digestion over a 24 hour cycle.
Aligning eating patterns with these rhythms supports digestion, hormone balance and gut health.
The body’s natural repair cycle
Between 10:00 pm and 2:00 am the body focuses on physical repair. Growth hormone is released, supporting the repair of muscles, tissues and cells. Digesting food during this window diverts energy away from these processes.
Between 2:00 am and 6:00 am the focus shifts to mental and emotional repair. REM sleep occurs during this time, supporting memory, emotional regulation and cognitive health. A rested gut supports a rested nervous system.
Avoiding late night eating allows the body to prioritise these essential repair processes.
Why digestion can worsen IBS symptoms
Digesting food requires coordination between the gut, nervous system, liver, pancreas and hormones. For people with IBS, any disruption in this process can trigger symptoms.
Poor digestion can lead to bloating, cramps, constipation or loose stools. These symptoms often come with secondary effects such as fatigue, anxiety, poor sleep and even skin issues.
This is why how and when you eat matters just as much as what you eat.
How intermittent fasting supports gut health
Intermittent fasting works by extending the body’s natural overnight fast. This gives the digestive system more time to rest and reset.
Benefits may include reduced bloating, improved bowel regularity, calmer digestion and better energy levels. Many people also notice fewer cravings and improved focus once blood sugar stabilises.
Intermittent fasting does not need to be extreme to be effective.
How to practise intermittent fasting safely
Daily intermittent fasting
I’ve personally practised intermittent fasting for many years, typically fasting for around 16 to 18 hours most days.
My routine is simple and flexible. I wake around 6 am, drink a pint of water, go for a short walk, have a cup of tea and allow my body to move naturally. After showering, I start my day.
I usually eat my first meal around 10 or 11 am. This might be a brunch style meal such as oats, eggs, a smoothie or leftovers from the night before. I continue to hydrate well during the day and eat my next meal around 4 or 5 pm.
Sometimes I’ll have a light snack around 6 pm, then I’m in bed by 9:30 pm. This gives my body a 16 to 18 hour break from digestion.
I follow this most days but I don’t stress if timings change. Listening to your body is key.
The 5:2 approach
Another option is the 5:2 method. This involves eating normally for five days and reducing intake on two non consecutive days.
On those two days, some people reduce calories to around 800, while others prefer a gentle juice fast. I personally find juice fasting easier and more effective.
I use this approach a few times a year, especially if I feel inflamed, sluggish or out of balance. It can be a helpful way to reset digestion and support gut health.
Occasional longer fasts
Occasionally, around two or three times a year, I’ll do a longer fast of around 24 to 36 hours when I feel run down or in need of a deeper reset.
This usually involves eating dinner, then fasting the following day with water or juices, alongside gentle activities such as walking, yoga or meditation.
This gives the gut a complete rest and often leaves me feeling refreshed and rebalanced.
The key to success with fasting and IBS
Intermittent fasting is not about deprivation. It is about nourishment, timing and giving the body space to heal.
Quality food during eating windows matters. Balanced meals with protein, healthy fats and fibre support blood sugar and prevent rebound cravings.
Fasting should always feel supportive, not stressful. If it increases anxiety around food, it is not the right approach.
Personalisation is essential, especially with IBS.
Want personalised guidance?
If you are curious about fasting but unsure how to approach it safely with IBS, you do not have to figure it out alone.
Understanding how food timing, digestion and lifestyle affect your gut can make a real difference. You’re welcome to book a free call to talk through your symptoms, routine and goals and see whether personalised support would help. Book your free call with Helen. today!