Refeeding Patients with Anorexia Nervosa: What Does Research Show?

While patients recovering from anorexia are often in dire need of sustenance, feeding them too much too soon can also be dangerous.

The issue is called anorexia refeeding syndrome, and it can lead to significant electrolyte imbalances and concerns with muscles, lungs, heart, and the brain. This problem causes swelling, confusion, and even death. 

Researchers say that up to 22% of people hospitalized for anorexia nervosa have mild cases of refeeding syndrome while in the hospital.¹ And while prompt treatment of the condition is important, preventing refeeding syndrome altogether is even better. 

What is Refeeding Syndrome?

Our bodies work best when they receive sustenance regularly, but they’re capable of adjusting when that process is disturbed. 

Without regular feeding, hormonal and metabolic shifts occur, allowing the body to continue functioning on less nourishment. However, while adjustment is technically a survival mechanism, it can lead to a number of serious health concerns.

Once these shifts occur, the body will react differently to food and drinks. Patients can become ill after eating a larger meal than they’re used to, and other molecular reactions could be dangerous or even deadly.

The adverse reactions to these fundamental changes are collectively known as refeeding syndrome.  
The condition is often associated with anorexia, but it can also happen to people with other medical conditions, like cancer, or those who have faced starvation for any number of reasons. Anytime a person loses a significant amount of weight and keeps it off for a prolonged period, whether intentionally or not, the risk of refeeding syndrome appears.

Signs of Anorexia Refeeding Syndrome

During starvation periods, the body will switch from using carbohydrates to using fat and protein as its primary source of energy. Certain compounds, including phosphate, magnesium, thiamin, and other minerals, are essential in making this change happen.² 

But when someone in this state suddenly eats a lot at once, these same compounds are called in to help the body process the food. The body will pull on any reserves it can locate, resulting in additional depletion and sickness.²

While any mineral imbalance is unhealthy, a drop in phosphate may have the most severe consequences. It can negatively impact almost every system in the body.

Very low phosphate levels can damage the heart and cause heart attacks. Unusual chest and heart sounds may occur in the early stages, or the person may complain of weakness or a fluttering chest sensation.

Other Signs of Anorexia Refeeding Syndrome

Low phosphate levels aren’t the only sign of refeeding syndrome. The condition can have a number of symptoms caused by nutrient imbalance and fluctuating hormone levels, including:³

• Confusion
• Convulsions 
• Coma
• Muscle weakness
• Seizures
• Trouble breathing

Blood tests may be able to reveal further signs of refeeding syndrome, including changes in magnesium levels. 

While these symptoms can be worrying to experience, they can also serve as early indicators of an oncoming problem, helping doctors spot and stop further complications before it’s too late.

Treating Refeeding Syndrome

Treating Refeeding Syndrome

Anyone with anorexia can develop refeeding syndrome during recovery. However, in the early stages of treatment, doctors typically control most of the refeeding process and can take quick action if symptoms appear.

In the very early stages of recovery, some people experiencing anorexia need to get their meals via a nasogastric tube. In these cases, doctors can adjust the flow of nutrients as needed. Magnesium and other critical electrolytes can also be administered via IV drip. 

These interventions can help people feel better and, in some situations, help to save their lives.

How Quickly Should Patients Start Eating Again?

While it’s generally agreed that introducing large meals too quickly can make people sick, some experts say refeeding strategies that are too conservative could do patients more harm than good. 

Studies have been conducted using as much as triple the amount of calories currently recommended for anorexia recovery, with no early signs of refeeding syndrome detected.⁵ 

Researchers point out that these larger meal plans are still set far below the average caloric needs of healthy people. However, they argue that an accelerated plan could help people heal more quickly. 

Plans like this have resulted in patients gaining up to 4 pounds per week, which is twice what has come to be expected in a traditional program.⁶ 

This difference is important, researchers say, as it allows patients to weigh more when they leave the hospital. And that early weight gain is associated with a more robust and lasting recovery.

What Can Families Do?

Watching a loved one go through anorexia recovery can be equal parts frightening and frustrating, but there are still some ways to participate in the process. 

Speak with the Medical Team

Ensuring the person gets care from a team familiar with refeeding syndrome symptoms is a good first step. 

The caregivers should understand what refeeding syndrome looks like and how it can be prevented. They should also provide ongoing monitoring to stay ahead of any medical emergencies. 

You can ask the team about the treatment program and any included protections. And you can keep checking in on progress and how the recovery is going.

Support Your Loved One

Most importantly, you can talk to your loved ones and help support them through this challenging process. Maintaining a position of love, patience, and understanding can help your family member feel comfortable and supported.

Ensuring someone that the doctors treating them have the best intentions in mind may be helpful. But simply being there for the person you love may be the biggest help of all. 

It can take time, but with some help, recovery from anorexia nervosa is always possible.

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Published November 26, 2025