Irritable bowel syndrome (IBS) is a functional disorder, this means there is a problem with the function of a part of the gut, but there is no abnormality in the structure of it. So, in IBS, the function of the gut is upset, but all parts of the gut look normal, even when looked at under a microscope. If the gut isn’t damaged then what is causing all the bloating, pain, diarrheoa, constipation and upset? Well stress or emotional upset often play a role in IBS. About half of people with IBS can relate the start of symptoms to a stressful event in their life. Symptoms tend to become worse during times of stress or anxiety. What you eat and when you eat can also affect IBS symptoms.
IBS sufferers need to have regular meals and take time to eat at a leisurely pace, also they need to avoid missing meals or leaving long gaps between eating. Eating late at night can make your IBS symptoms worse. Research has shown that eating behaviour and circadian rhythm are proving to be important factors in IBS, sleep quality, obesity and depression/stress. Disruption of the circadian cycle is strongly associated with metabolic imbalances. There is even a name for those who eat late at night, they have “night-eating syndrome” which is characterised by increased late-night eating, insomnia, a depressed mood and distress. This has even been measured biochemically. Reducing this stress can improve your IBS symptoms.
Eating a large meal late at night means going to bed with a large amount of undigested food and acid in the stomach, and this increases the risk for acid reflux. You need to allow at least three hours after you eat before bed time: digestion slows down at night, and a full stomach may interrupt sleep which is stressful in itself. The heavier the meal, the longer it takes for your stomach to settle.
Those with IBS symptoms also need to get tested for food intolerance; just modifying your eating patterns may not be enough on its own. It is what you eat, as well as when you eat, that cause the problems. In one study of 777 IBS sufferers, 84% reported an improvement in their symptoms when they removed foods from their diet identified by the YorkTest Food Intolerance Test. The study didn’t include looking at the impact of late night eating, but it is clear now that just a few changes to your eating habits can make a huge difference to your quality of life.