Eating a balanced diet focusing on nutrient-dense foods is important for everyone. This is especially important for people with chronic lymphocytic leukemia (CLL).

While there is no set diet for CLL, following certain guidelines may help support the body and immune system. This may help the body tolerate treatment and to prevent foodborne illnesses.

Doctors may recommend that a person with CLL follow a supportive diet during and after treatment. This may involve nutrient-dense food choices while limiting other options such as processed foods.

A person may consider working with a dietitian or nutritionist for specific guidance. They may be able to advise on eating plans, changes in appetite and weight, and how to manage treatment side effects related to appetite and weight.

In this article, we will discuss foods and drinks that people with CLL may want to consider adding to their diet, as well as what to avoid.

A person preparing broccoli, which is a suitable food to include in a CLL diet.Share on Pinterest
agrobacter/Getty Images

Poor diet is an important modifiable risk factors for cancer. A 2019 study notes that approximately 4.4% of new cancer cases in 1 year had a direct connection to poor diet.

Avoiding certain foods may help support a healthy immune system and prevent complications. This does not necessarily mean avoiding these foods will improve treatment. However, it may support an overall healthy body and treatment.

Western diet

A diet for people with CLL may involve reducing processed foods. Diets such as the Western diet, or the Standard American Diet, tend to be high in processed food intake. A 2018 study notes a potential association between the Western diet and CLL.

Key features of the Western diet includes high intakes of:

  • high fat dairy foods
  • refined grains
  • processed meat
  • high caloric drinks
  • sugary foods and snacks
  • fast food or convenience food

While the Western diet may increase the potential risk of CLL, more research is still necessary.

It is also important to consider how genetics and the environment may also interact with the diet. However, guidelines generally agree that it is beneficial to limit or avoid many of the items associated with the Western diet.

Food safety

Cancer treatments, such as chemotherapy and radiation therapy, may weaken the immune system. This could make a person more susceptible to infections. Therefore, it is important that people follow good food hygiene and avoid foods often associated with illnesses.

A doctor may advise:

  • avoiding raw or undercooked meat and fish, or other foods that may include raw ingredients, such as raw eggs or pate
  • avoiding unpasteurized products, which could include fruit juices, dairy products, and honey
  • only drinking tap or bottled water
  • only eating nuts and dried fruits that have undergone heat treatments
  • trying to avoid reheating foods where possible, and also storing leftover correctly
  • remembering to wash hands regularly, and to also wash vegetables

The exact dietary recommendations for any given person will vary to some degree, and there is no set diet to follow for CLL. In general, doctors may recommend a healthy and energy-boosting diet, which may help support cancer treatment or prevention.

The 2020 American Cancer Society guideline says diets that may help reduce cancer risk vary. However, they do share common patterns. These patterns may include:

Plant-based

Diets rich in plant-based foods may be supportive for people with CLL. Plant-based diets are associated with:

  • reduced inflammation
  • reduced oxidative DNA damage
  • higher levels of beneficial gut bacteria
  • improved insulin response

Therefore, it may be advisable for people to incorporate more plant-based foods into their diet. Examples of healthy plant-based foods can include:

  • nonstarchy vegetables
  • whole fruits
  • whole grains
  • nuts
  • seeds
  • legumes

Healthy protein

These diets also typically include healthy protein sources, such as:

  • legumes
  • fish
  • poultry

Healthy fats

These diets also tend to include healthy sources of fats, such as both monounsaturated and polyunsaturated fatty acids.

Examples of monounsaturated fat sources include:

  • olive oil
  • avocado
  • nuts
  • seeds

Examples of polyunsaturated fats include omega-3 and omega-6 fatty acids from:

  • flax seed
  • chia seed
  • hemp seeds
  • fatty fish such as tuna, salmon, and sardines
  • soybeans
  • walnuts

Antioxidants

Antioxidants are another important factor for those with CLL, as CLL may weaken the immune system and make the body more prone to infections.

A 2014 study suggests that increasing antioxidant intake, in addition to overall healthy lifestyle choices, may improve the quality of life for people with CLL. It also may reduce the risk for infections and complications.

Changing to a dietary pattern that favors an increased intake of whole, natural foods may help naturally increase the levels of antioxidants in the diet.

Some examples of antioxidant-rich foods include:

  • berries
  • green tea
  • dark chocolate
  • dark, leafy greens

Types of diets

A good example of this dietary pattern is the Mediterranean diet. This diet emphasizes fruits, vegetables, and whole grains, and it includes less dairy and meat than a typical Western diet. Typical features of the diet include a high intake of:

  • vegetables
  • legumes
  • fruit
  • fish
  • olives
  • vegetable oil

Other dietary patterns may have similar characteristics, including:

For people with CLL, and cancer in general, advice for drinks usually involves eliminating certain types of drinks or replacing them with healthier options.

Reduce or eliminate alcohol intake

The 2020 guidelines advise that it is best to avoid alcohol completely. This is because alcohol has carcinogenic effects in the body, such as:

  • damaging DNA and proteins
  • oxidative stress
  • increased cell proliferation
  • reduced DNA repair
  • difficulty absorbing nutrients

If eliminating alcohol is not possible, people can try to reduce consumption to no more than 1 drink per day for women and 2 drinks per day for men.

A standard drink includes:

  • 12 ounces of beer
  • 5 ounces of wine
  • 1.5 ounces of 80-proof alcohol

Drink more water

Water is a healthy choice. However, some may feel it is too bland to enjoy regularly. Finding ways to add flavor to water may make it easier to drink more.

Some tips to drink more water may include:

  • drinking unsweetened sparkling water
  • adding citrus fruits such as lemon, lime, or grapefruit to the water
  • making flavored water by adding fruits or vegetables to the water and letting it soak
  • drinking herbal tea

Reduce sugary drink intake

As part of moving away from the Western diet, it is important to reduce or eliminate sugar-sweetened beverages. This includes many types of:

  • soda
  • sweetened coffee drinks
  • energy drinks
  • sports drinks
  • fruit drinks
  • sweetened water drinks

Some treatments for CLL, such as chemotherapy or radiation therapy, may cause side effects that make it difficult to eat, such as:

  • loss of appetite
  • dry mouth and throat
  • difficulty swallowing or chewing
  • nausea
  • vomiting
  • diarrhea or constipation

Doctors may recommend managing these side effects with medications if the person cannot eat or drink sufficiently. Changes to the diet may also help to some degree.

For example, there may be ways to make food easier to chew or more comfortable to eat. This might include making:

  • pureed vegetable soups
  • pureed fruits, such as applesauce
  • mashed potatoes or sweet potatoes
  • mashed bean dishes
  • soft egg dishes such as scrambled eggs
  • oatmeal or porridge

Some foods may help soothe symptoms such as a sore throat or dry mouth. Warm, rich liquids, such as soup broth or herbal tea, may soothe the throat while also adding more water to the diet.

If cold is more soothing for the throat, chewing frozen berries may help provide some relief.

CLL treatment can vary for each person living with this condition. Doctors may recommend changing the diet to support the body and immune system, and to help ease symptoms or complications of CLL or treatment.

The best dietary pattern may vary in each case. However, it generally includes a focus on a diet that may limit red meats, processed foods, and added sugars. A person may also consider working with a dietician to create a suitable diet plan and get adequate nutrition.