What is a neutropenic diet for patients with low neutrophil count, typically those undergoing chemotherapy, radiation therapy, or with certain medical conditions that compromise the immune system?

What is a Neutropenic Diet?

A neutropenic diet is a historically restrictive dietary approach—also called "germ-free," "low bacterial," or "sterilized" diet—that limits consumption of fresh fruits, vegetables, and other foods thought to harbor bacteria in immunocompromised patients; however, current evidence does not support its use, and it should NOT be prescribed. 1, 2

Historical Context and Definition

• The neutropenic diet was instituted in the 1980s as a presumptive means of preventing foodborne infections in patients with severe immunosuppression by restricting foods that might harbor pathogenic organisms colonizing the gastrointestinal tract 1
• The diet typically restricts fresh fruits and vegetables, requiring all produce to be cooked, along with limitations on other foods perceived as high-risk for bacterial contamination 3, 4
• No universal definition exists—exactly which foods are restricted varies greatly by institution, reflecting the lack of standardized evidence-based criteria 3

Current Evidence Against Neutropenic Diets

The most recent and highest quality guidelines explicitly recommend AGAINST using neutropenic diets:

• ESPEN 2021 Hospital Nutrition Guidelines state that neutropenic diets "shall not be used" in neutropenic patients with cancer, including hematopoietic cell transplant patients (Grade A recommendation) 1
• A systematic review and meta-analysis of 6 studies with 1,116 patients (69% undergoing hematopoietic cell transplants) found no statistically significant difference in major infections or bacteremia/fungemia rates between neutropenic and usual diets 1
• In hematopoietic cell transplant patients specifically, neutropenic diets were paradoxically associated with slightly HIGHER infection rates 1

Key Studies Demonstrating No Benefit:

• A retrospective review of 726 consecutive HCT patients found infection rates were HIGHER among the 363 patients receiving a neutropenic diet compared to 363 patients on a general hospital diet 1
• An RCT in 78 AML patients receiving induction chemotherapy showed no difference in major infection rates, fever of unknown origin, or survival between those eating only cooked versus fresh fruits and vegetables 1, 2
• A pediatric oncology RCT found no difference in infection rates between children receiving neutropenic versus standard diets prepared according to FDA food safety guidelines 1

Harms of Neutropenic Diets

Restrictive neutropenic diets cause nutritional deficiencies without providing infection prevention benefits:

• The diet is associated with deficiencies in dietary fiber, vitamins C, A, and D, magnesium, and calcium—nutrients critical for immune function and recovery 4
• Cooking processes required by neutropenic diets cause significant nutrient losses, particularly boiling which depletes vitamins C, A, and K, phenolic compounds, flavonoids, and minerals (calcium, zinc, manganese, magnesium, copper, iron) 4
• The restrictive nature reduces dietary variety and may contribute to malnutrition in cancer patients who already experience poor oral intake 4, 5
• ASCO Expert Panel concluded that harms of restrictive neutropenic diets may outweigh potential benefits 2

What Should Be Done Instead: Food Safety Guidelines

Current best practice emphasizes standard food safety practices rather than food restrictions:

• Hand washing is the single most important intervention 6, 7
• Safe food handling includes proper steps in food shopping, storage, preparation, thawing, cooking, serving, refreezing, and cold storage 1, 2
• These food safety guidelines are recommended by the CDC, ESPEN, and ASCO as superior to restrictive diets 1, 2, 6

Clinical Bottom Line

There is no published evidence supporting a low bacterial diet during the neutropenic phase, making it difficult to justify any form of neutropenic diet restriction 1. The emerging practice to minimize foodborne infection risk emphasizes strict adherence to food safety guidelines rather than dietary restrictions 1, 2. Patients should follow standard safe food-handling practices while maintaining adequate nutrition to support immune function and recovery during chemotherapy 2, 6.