Why Digestive Issues Are So Common in Eating Disorders (and Why They Get Better)

Have you been experiencing bloating, constipation, stomach pain or feeling full after only a few bites? It’s so easy to point the finger at a new food intolerance but if you’ve been restricting your food intake or participating in other disordered eating behaviours, it’s probably not a single food's fault.

Digestive issues are incredibly common in people with eating disorders or people not eating enough, and they can be one of the most frustrating parts of recovery. Many people worry that something is seriously wrong with their gut, when in reality, these symptoms are often a normal response to not eating enough for a prolonged period.

The good news? In most cases, your digestive system is capable of recovering.

Why do eating disorders affect digestion?

Your digestive system relies on regular nourishment to function properly.

When your body doesn't receive enough food or nutrients, it shifts into survival mode. Energy is diverted away from processes that aren't essential for immediate survival, including digestion.

Over time, this can lead to:

Slower stomach emptying (called delayed gastric emptying)
Reduced digestive enzymes and hormones
Weakened muscles in the stomach and intestines
Slower movement of food through the gut

In a healthy digestive system, food moves through the intestines in around 1.5 hours. In someone who is undernourished, this can take up to five hours.

Common digestive symptoms during an eating disorder

As digestion slows, it's common to experience:

Bloating
Constipation
Diarrhoea
Excess wind or gas
Abdominal pain
Feeling full very quickly, even after eating small amounts

These symptoms can occur in people with restrictive eating disorders, but they're also common after periods of under-eating, irregular eating or frequent vomiting.

Why constipation happens

Your bowel needs enough food passing through it to stimulate regular bowel movements.

If you're eating very little or skipping meals, there simply isn't enough bulk moving through your digestive tract. Combined with slower gut muscles, this often leads to constipation.

Frequent vomiting can also disrupt your gut's normal rhythm, making digestion even slower.

A word about laxatives

It can be tempting to reach for laxatives when constipation becomes uncomfortable, but they're rarely the answer.

Overusing laxatives can actually make constipation worse over time by weakening the bowel muscles. They can also cause:

Bloating and cramping
Excess gas
Mucus or blood in the stool
Loss of bowel control (incontinence)
In severe cases, damage that can permanently affect bowel function

While many of these effects improve after stopping laxatives, some damage can be long-lasting.

Rather than helping your gut recover, laxatives often prevent it from rebuilding its normal strength and function.

The best way to improve digestion during recovery

The most effective treatment for digestive symptoms is also the one that can feel the hardest: eating enough food, consistently.

Your gut is like any other muscle in the body. The more consistently it is used, the stronger and more efficient it becomes.

As nutrition improves, digestion usually begins to improve too.

It's important to know that symptoms often get worse before they get better. Increased bloating or discomfort in the early stages of recovery isn’t a red flag, it often means your digestive system is waking up again.

Tips to help manage bloating and discomfort

While your gut is recovering, these strategies can help:

Continue eating regular meals and snacks, even if you feel uncomfortable.
Use a warm heat pack or hot water bottle on your abdomen.
Go for a gentle walk or do another light, distracting activity after meals.
Be patient. Recovery takes time, and so does gut healing.

The bottom line

Digestive symptoms can feel overwhelming, but they're an incredibly common consequence of undernutrition and eating disorders.

Most importantly, they are usually temporary.

With adequate nutrition, regular eating and ongoing support, your digestive system has an amazing capacity to heal. While the discomfort can make recovery feel difficult, it's often a sign that your body is beginning the process of repairing itself.

If you're concerned about ongoing digestive symptoms, we’re here to help. Reach out today to start working with a specialised TWC dietitian.