Written by Talia Cecchele
Digestive issues are one of the most common side effects of an eating disorder, irrespective of type of eating disorder or body weight or size. People can experience digestive issues by engaging in any disordered eating and compensatory behaviours. Studies suggest that specifically for anorexia nervosa, greater than 95% of people will experience gastrointestinal (GI) complaints .
Why do digestive issues occur?
Digestive issues in eating disorders and disordered eating can be related to a pre-existing condition such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD), engaging in eating disorder behaviours (e.g. self-induced vomiting or laxative abuse), malnutrition and weight loss or a combination of these. However, most commonly it is functional in nature meaning that digestion is negatively impacted due to starvation.
Vomiting and laxative misuse can interfere with normal GI functioning by slowing down digestion, causing loss of muscle tone, bloating, gas and abdominal pain. Laxative abuse can have severe side effects including blood or mucus in the stool, incontinence and worst case paralysis of the intestine (which can lead to surgical removal of part or all of the colon) and increased risk of colon cancer.
In starvation, the cave man brain doesn't want to spare a single bit of energy on digestion because normal digestion isn't necessary for human survival. When the body isn't receiving adequate energy from food, it needs to source fuel from somewhere else and the body does this by slowing down metabolism and breaking down muscles and converting the protein into energy. As a result from this and the GI tract being underused due to restriction, the muscles of the stomach and intestines lose tone and become weak. Also, in starvation fewer enzymes and hormones required for digestion are produced, further impacting digestion.
What are the common digestive issues experienced?
Digestive issues experienced by people with disordered eating and eating disorders include:
Gastroparesis (slow stomach emptying) as a result of starvation and calorie restriction. This can make someone feel "Christmas lunch" full even after eating half a sandwich
Bloating & abdominal distention as a result of gastroparesis and/or weak abdominal muscles and reduced abdominal fat. When abdominal muscles are weak and there is an insufficient layer of fat the abdominal wall can't hold in the food and you can "see" you meal
Constipation due to gastroparesis, dehydration and simply not having enough volume of food in the gut
Early satiety (feeling full quickly) and feeling full all the time
IBS - type symptoms including food intolerances such as transient (temporary) lactose intolerance (note it is not recommended to follow an elimination diet during nutritional rehabilitation - we need to give the gut nutrition, not restrict it further).
During the early stages of nutritional rehabilitation, it can be easy to think that feeling full on a small amount of food means that you don't have to eat as much or not follow the meal plan recommended by your Dietitian. Eating disorders like this logic, however not eating and prolonging nutritional rehabilitation will only make your digestive symptoms worse as the gut remains undernourished. In the initial stages (first few months at least), meals will be eaten according to time and be prescriptive rather than relying on hunger and fullness cues.
How to manage digestive issues in recovery
Eating disorder recovery, specifically nutritional rehabilitation is often complicated by digestive discomfort and the misinterpretation of fullness being experienced as weight gain or feeling "fat." GI issues will improve with time with nutritional rehabilitation, weight restoration and cessation of any behaviours interfering with digestion. There are some practical tips to help ease the discomfort following a meal:
Wear loose fitting clothes during and after meals. Clothes that fit tightly around your stomach or even tight leggings can increase bloating and abdominal pain
Use a hot water bottle or sip on herbal tea after a meal (peppermint is a good flavour)
Hug a pillow or blanket
Distract yourself with a puzzle, calling a friend, knitting, watching a movie or any other activity
Talk to someone! Being open with how you feel and the discomfort you are experiencing is important as sometimes you might need to hear a rational voice when the eating disorder voice is loud
Avoid lying flat for at least 30-60 minutes after a meal. Let gravity help move things along
Avoid filling up on too many fluids with your meals, sip them in between
Practice breathing techniques or meditation
Be patient, it will get better!
Your doctor or dietitian might recommend medication to ease the discomfort from gastroparesis or constipation. Medications like metoclopramide, fibre supplements or stool softeners (not stimulants) can be helpful temporarily.
It can take time for your gut health to return to normal, and unfortunately some people will experience lasting side effects as a result of chronic restriction and starvation. If you are concerned about your digestion please don't restrict your diet or engage in unhealthy behaviours or self-medicate. It is important you seek professional medical advice.
 Kessler U, Rekkedal GÅ, Rø Ø, et al. Association between gastrointestinal complaints and
psychopathology in patients with anorexia nervosa. Int J Eat Disord. 2020;53:802–806. https://doi.org/10.1002/eat.23243
Talia Cecchele Nutrition is a team of registered dietitians specialising in eating disorders and disordered eating. We aim to bring balance back to nutrition, help you to break free from food rules and find food freedom. To enquire about private consultation please fill out a contact form.