Refeeding Edema & Pseudo-Bartter Syndrome in Eating Disorder & Severe Malnutrition Recovery

Edema – fluid retention and swelling – is a common side effect during the refeeding process. Edema can cause physical discomfort, weight gain and anxiety in individuals recovering from eating disorders. Causes of edema include refeeding syndrome, pseudo-Bartter syndrome and low albumin levels. Thankfully, edema is temporary with medical monitoring and continued refeeding.

What is Edema?

Edema occurs when fluid builds up in tissue, leading to swelling. It most commonly affects the feet, ankles and legs, but other areas of the body can also be impacted. The buildup of fluid can exert pressure on nerves, blood vessels and nearby structures, resulting in pain and discomfort. Other signs of edema include:

• Skin tightness
• Tenderness
• Soreness
• Bruising or discoloration
• Heaviness
• Difficulty walking or moving the limb

Edema can appear during the refeeding process in patients being treated for eating disorders and severe malnutrition.

Is Edema Permanent?

Thankfully, edema is not permanent. Edema is usually temporary and reversible, resolving once the underlying cause is treated. With proper medical care and time, the body naturally restores its fluid and electrolyte balance, and the swelling subsides.

3 Types of Edema

There are several forms of edema, each with distinct causes and considerations. Understanding the differences between refeeding edema, pseudo-Bartter edema and low albumin-related edema can help guide effective care and ease distress during recovery.

Refeeding edema

Refeeding edema is a form of fluid retention that typically occurs within two weeks of refeeding with normal serum albumin levels.^1,2Refeeding edema is common in patients with eating disorders, with about 20% of patients with restrictive eating disorders developing edema during refeeding.¹ While those with restrictive eating disorders are at the greatest risk, all individuals with malnutrition undergoing refeeding are at risk. This includes those with:

• Anorexia nervosa, including “atypical” anorexia nervosa
• Bulimia nervosa
• Avoidant/restrictive food intake disorder (ARFID)
• Non-eating disorder malnutrition

Why does refeeding cause edema?

While refeeding edema isn’t completely understood, the prevailing theory is that an increase in insulin is a major contributor to the development of edema.² As insulin is secreted, it causes the kidneys to retain salt and increase water reabsorption. Fluid retention primarily occurs in the lower extremities as gravity causes water retention in the legs and feet.

Our study about phosphate replacement suggests that phosphate therapy may be related to the development of refeeding edema.² However, additional studies are needed to fully understand the hormonal changes that lead to refeeding edema.

Hypoalbuminemic (protein-deficiency) edema

Individuals with an underlying inflammation or hypoalbuminemia are at risk for edema due to low albumin levels. Proteins, such as albumin, pull water into the blood vessels and prevent fluid from leaking into other tissues.  When albumin drops to a low level (hypoalbuminemia), this fluid can escape into other parts of the body.

Inflammation causes a decrease in albumin levels through various mechanisms, although hypoalbuminemia does not seem to be associated with malnutrition itself. When hypoalbuminemia is identified, it should prompt one to look for other medical conditions, such as:

• Liver disease
• Kidney disease
• Inflammatory bowel diseases
• Celiac disease
• Rheumatoid arthritis
• Infection

Hypoalbuminemia alone does not fully explain this form of edema, and it may arise via multiple mechanisms in those with malnutrition.³

Pseudo-bartter edema

Individuals with low serum albumin, individuals who spend a significant amount of the day standing, or with a history of purging behavior, like those with bulimia nervosa and anorexia nervosa binge eating and purging subtype, are at risk for pseudo-Bartter Syndrome, which includes a variety of findings like:⁴

• Hypokalemia (low potassium)
• Hypochloremia (low chloride)
• Metabolic alkalosis
• High blood pressure
• Increased urinary excretion of sodium, chloride and potassium

These electrolyte disturbances are accompanied by a state of chronic dehydration, which leads to increased secretion of aldosterone from the adrenal glands to prevent fainting from low blood pressure via increasing sodium reabsorption in the kidneys.⁵ The end result is hypokalemia, metabolic alkalosis and edema formation due to the new salt-retaining state.⁵

The elevated serum aldosterone levels take one to three weeks to return to normal once hydration levels return to normal.⁵ Serum aldosterone levels are not routinely monitored and should not guide clinical decision making. When patients enter treatment and stop purging, their persistently abnormally elevated aldosterone levels lead to rapid fluid retention over the course of just a few days.⁵

Emotional Impact of Edema

Edema can cause emotional distress for patients. The appearance and rapid weight gain – despite not being fat tissue – can cause patients to begin questioning treatment. It can trigger overwhelming feelings of discomfort, doubt and low self-esteem which can make those suffering from eating disorders feel compelled to return to disordered eating patterns.

Edema can also be painful and uncomfortable, which can make an important first step towards recovery feel like a mistake.

Treatment for Edema

Effective treatment of edema targets both the underlying physiologic causes and eating disorder behaviors that can prolong swelling.

Patient education

Providers should discuss the mechanisms of edema with patients, particularly for patients with eating disorders who may have image concerns in response to edema formation. Patients should be reassured that edema is temporary, treatable and is not fat gain.

Interrupting purging behavior

For pseudo-Bartter syndrome, the primary treatment is cessation of purging behaviors. Once a patient stops self-induced vomiting or laxative use, serum potassium values and intravascular volume will normalize, and edema will gradually subside.

Spironolactone

Spironolactone, a medication that blocks the effects of aldosterone, can be used for pseudo-Bartter edema. This should be done under the direct supervision with frequent assessment and appropriate lab monitoring by an experienced clinician.

Compression

The use of compression garments can help support veins and lymph vessels, returning fluid to the circulatory system.

Elevation

Elevating the limb above the heart takes advantage of gravity to improve drainage and decrease swelling.

Correcting hypoalbuminemia

The underlying cause of the hypoalbuminemia first needs to be medically treated. The treatment of the edema is managed similarly to the interventions above.

H2: Find expert eating disorder care at ACUTE

Edema associated with eating disorders can be physically uncomfortable and emotionally distressing, especially during refeeding. With support from experienced medical professionals, edema can be temporary and manageable.

Get started with a free assessment.

References

1. Khatri, V., Stein, A., Mehler, P. S., & Gibson, D. (2025). Association of phosphate supplements with refeeding oedema in restrictive eating disorders. European Eating Disorders Review, 33(3), 589–594. https://www.acute.org/association-phosphate-supplements-refeeding-oedema-restrictive-eating-disorders
2. da Silva, J. S. V., D. S. Seres, K. Sabino, et al. 2020. “ASPEN Consensus Recommendations for Refeeding Syndrome.” Nutrition in Clinical Practice 35, no. 2 (April): 178–195. https://doi.org/10.1002/ncp.10474.
3. Morlese, J., Forrester, T., Badaloo, A., Del Rosario, M., Frazer, M., & Jahoor, F. (1996). Albumin kinetics in edematous and nonedematous protein-energy malnourished children. American Journal of Clinical Nutrition, 64(6), 952–959. https://doi.org/10.1093/ajcn/64.6.952
4. Bahia, A., Mascolo, M., Gaudiani, J. L., & Mehler, P. S. (2011). PseudoBartter syndrome in eating disorders. International Journal of Eating Disorders, 45(1), 150–153. https://doi.org/10.1002/eat.20906
5. Swanson, L., Herbert, M., & Mehler, P. S. (n.d.). Causes and management of edema in patients with eating disorders. Eating Disorders Review, 31(2). https://edr.iaedpfoundation.com/causes-and-management-of-edema-in-patients-with-eating-disorders/