An Overview of the Neutropenic Diet

The neutropenic diet is a way of eating that may reduce the risk of developing bacterial infections from certain types of foods. Also known as a low-microbial diet, it is often recommended for people with severely weakened immune systems, such as cancer patients undergoing chemotherapy.

The neutropenic diet is named after a medical condition called neutropenia. Neutrophils are an important type of white blood cell (WBC) that help fight infection. When the neutrophil count drops dangerously low, people are considered neutropenic. Neutropenic people can easily get bacterial infections from food and become ill.

This article will review the key features of the neutropenic diet and discuss its effectiveness.

Food Safety in Neutropenia

Though the neutropenic diet is somewhat controversial, the FDA does endorse safe food handling practices for those experiencing neutropenia. Preventing bacterial transmission is the primary aim of the neutropenic diet. Although most healthy people will recover from foodborne illnesses quickly, those with a weakened immune system may not.

Your primary line of defense against infection is good handwashing. Properly preparing and storing food also reduces the risk of developing a bacterial infection from food.

Food Preparation Guidelines

Bacterial contamination often occurs during food preparation. Here are some guidelines to follow when preparing food for yourself or a loved one on a neutropenic diet:

• Wash hands with warm soapy water for 20 seconds before and after preparing meals.
• Wash and scrub vegetables thoroughly with water before cutting or peeling. Wash lettuce leaves one at a time.
• Wash and scrub raw fruits, including thick-skinned fruits like oranges and melons.
• Rinse "prewashed" salads.
• Toss out foods that smell foul or show signs of spoilage.
• Wash the tops of canned foods with soap and water before opening.
• Use a different utensil for eating and tasting foods while cooking. 
• Throw away eggs with cracked shells.
• Use separate cutting boards for meat and produce.
• Use a meat thermometer to make sure meats are cooked to the proper temperature.
  

Food Storage Guidelines

Once prepared, here are ways to safely store foods consumed on a neutropenic diet:

• Keep hot foods hot (over 140 F).
• Keep cold foods cold (under 40 F).
• Eat defrosted foods right away. Do not refreeze.
• Avoid leaving food on the counter for long periods of time.
• Do not thaw meat, seafood, or chicken at room temperature. Use the microwave or refrigerator instead.
• After buying perishable foods, eat them within two hours.
• Leftovers should be eaten within 48 hours and reheated only once. 
• Eggs, cream, and mayonnaise-based foods should not be kept outside the refrigerator for more than an hour.
  

Foods to Avoid

Depending on the recommendations from your oncology team, you may be advised to avoid certain foods while undergoing cancer treatment. Foods typically avoided on the neutropenic diet include:

• Raw meats and seafood (including sushi)
• Raw nuts or fresh nut butter
• Any foods that contain raw eggs (including Caesar salad dressing or homemade mayonnaise)
• Soft and aged cheeses
• Unpasteurized cheeses, milk, fruit juices, and vegetable juices
• Fermented dairy products, such as kefir
• Bulk-bin cereals and grains
• Undercooked or raw brewer's yeast
• Cream-filled pastries that are not refrigerated
• Uncooked vegetable sprouts, such as alfalfa, bean, and clover sprouts
• Raw honey or honeycomb
• Water from a lake, spring, stream, or well
• Herbal-supplemented water
• Refrigerated grocery store salsas
  

Effectiveness

Although the neutropenic diet has been prescribed to cancer patients for years, there is no scientific evidence that shows it reduces infection rates during cancer treatment. In fact, these strict recommendations may be doing more harm than good.

Patients undergoing chemotherapy often experience a decrease in quality of life due to fatigue, loss of appetite, and stress. Not allowing cancer patients to eat and drink foods that satisfy the body and the mind can contribute to nutritional deficits and depression.

Conclusions from a 2018 study of children receiving immune-suppressive chemotherapy confirmed that neutropenic diets should be replaced with the FDA's approved food safety guidelines.

In addition, the neutropenic diet is not standardized, meaning there are no published guidelines on the correct way to follow it. Instead, each cancer center adjusts the diet requirements according to their preference. This can lead to inconsistency and confusion for patients.

Potential Challenges

Maintaining good nutrition during cancer treatment is further complicated by other side effects of chemotherapy. Some of these include:

• Mouth sores: Painful sores in the mouth are common during chemo. Choosing foods that are less likely to irritate the mouth is essential. Avoid acidic foods such as citrus and tomato-based products. Also refraining from foods with sharp edges, like toast or chips, is helpful.
• Taste changes: Some cancer medications can result in a metallic or salty taste in the mouth. Choosing foods with strong flavors and eating with plastic utensils can help improve this side effect.
• Nausea and vomiting: Nausea and vomiting interfere with the desire and ability to eat. There are several remedies available to alleviate these symptoms. Talk to your oncology nurse about what options are best for you.
• Loss of appetite: Chemotherapy and radiation can decrease appetite. Working with a certified dietitian can help you maintain your calorie intake during this time.
• Cancer fatigue: Fatigue is a common symptom during cancer treatment. Not having the energy to buy groceries or prepare meals can negatively impact your health. Using grocery delivery services and asking others for help is essential to maintaining your well-being.

Other Ways to Reduce Infection Risk

In addition to safe food practices, here are other ways to reduce your risk of developing an infection during cancer treatment:

• Eliminate contact with birds, turtles, and reptiles such as lizards and snakes. These animals can carry the bacteria Salmonella, which can be life-threatening in people with severely suppressed immune systems.
• Assign cleaning the cat litter box to a family member or friend. Litter boxes are a common source of a parasitic infection called toxoplasmosis.
• Avoid crowds or enclosed spaces, such as airplanes, especially during cold and flu season.

Summary

The neutropenic diet is a nutritional plan for those with a weakened immune system due to cancer treatment. Since contaminated food can cause bacterial infections, the neutropenic diet recommends safe food handling in addition to avoiding certain types of foods.

However, studies have not proved that the neutropenic diet reduces the risk of developing infections. Therefore, some oncology clinics emphasize safe food handling practices rather than following strict neutropenic diets. Talk to your oncology nurse about how to stay infection-free during cancer treatment.