Navigating Cancer Nutrition: Insights from an Oncology Dietitian

What is an oncology dietitian?

An oncology dietitian is a registered dietitian who specializes in oncology, or cancer, nutrition. Oncology dietitians are a crucial part of the care team working with your doctors, nurses, genetic counselor, social worker/case manager, and more to provide evidenced based care. 

What credentials should you look for?

You should look for a Registered Dietitian Nutritionist (RD or RDN). All dietitians are nutritionists, but not all nutritionists are dietitians. It’s critical to work with a registered dietitian, as they are accredited nutrition professionals that have training in the pathophysiology and appropriate management of disease states, like cancer. Read more on the difference between dietitians and nutritionists here. In a hospital setting, you will only see dietitians, although they may introduce themselves as a nutritionist. If you are searching online, please make sure to ask for their credentials.

If available in your area, a dietitian that also holds a CSO certification is something else to look for. This is a certification by the Commission on Dietetic Registration that stands for Board Certified Specialist in Oncology Nutrition. Part of the eligibility requirements to sit for this certification exam includes documenting over 2,000 hours in oncology nutrition. 

What areas do we work in?

As an oncology dietitian there are many areas you can work in, and the hospitals may structure their dietitian staff differently place to place. Where I worked, we had inpatient oncology dietitians and outpatient oncology dietitians in our department. Inpatient oncology dietitians meet with patients with cancer who are admitted to the hospital. This can include those admitted for a scheduled surgery related to their diagnosis, those receiving a bone marrow transplant, or those who have a medical reason for admission that may or may not be related to their cancer. Outpatient oncology dietitians meet with patients who are not currently admitted to the hospital, but may be here for a medical oncology appointment, or in the infusion or radiation centers receiving treatment. We also can meet with patients and families via phone or telehealth.

At some places with multiple dietitians, they may have oncology dietitians that specialize or follow certain types of cancer by splitting up the main cancer types between the staff, and each specialize further. Where I worked, I covered all types of cancer, and was able to meet with patients and families who ranged from day one of diagnosis to survivorship. 

In addition to meeting with patients, where I worked we had multidisciplinary tumor boards, where cases were presented and all members from the care team attended, including oncology dietitians. I also spoke at support groups within the community to talk about different cancer nutrition topics, and I also presented at Cancer Symposiums at our hospital to share oncology nutrition research and guidelines with our care teams. 

Oncology Nutrition Goals 

While working with patients, we assess nutritional status, and make nutrition diagnoses, that we then develop goals and a treatment plan for. 

One consistent nutrition goal is to prevent malnutrition, work towards improving nutritional status until existing malnutrition is resolved, or work towards maintaining current status and preventing worsening malnutrition as we are not always able to resolve malnutrition. There are many variables, but those with cancer are at an increased risk of developing protein-calorie malnutrition, which can lead to poor outcomes and ability to tolerate treatment.

Cancer nutrition goals are individualized depending on many factors (type of cancer, type of treatment, patient goals, nutrition diagnoses, etc.). Many of the patients I worked with were in active treatment, and in a catabolic state. This means the body is ‘burning’ or using more muscle and energy stores than it is able to replete, and leads to muscle and fat loss. For some patients, if they continue to eat what is ‘normal’ for them prior to a diagnosis, they may see unintentional weight loss, because they are burning through stores faster than they are repleting them which leads the body to break down muscle and fat for fuel if it is not getting enough through food. In this scenario patients have a higher recommended daily calorie and protein goals in order to maintain their body mass, and prevent muscle and fat loss. Calculating these numbers specific to each patient and performing a food recall to determine current protein and energy intake helps us work to make changes to meet their nutrition needs, and is important in preventing malnutrition.  

Diagram of the digestive system. Source: National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health

Although I worked with all types of cancer, a large percentage of patients I worked with are those with cancers that impact the digestive system.

Having cancer in the digestive tract can impact it’s function and cause issues with absorption and digestion of nutrients. This also includes those who have surgery as part of their treatment plan, as parts of the digestive tract may be removed, and we work to make changes to feeding and intake as indicated. 

Another major focus of my work in oncology nutrition is to address any side effects with treatment. These can impact a patient’s ability to fuel their body enough to prevent malnutrition and/or dehydration. Examples include side effects impacting taste and smell, appetite, early satiety, and changes to stooling (diarrhea and/or constipation) that can equally negatively impact quality of life. 

Being a resource to patients, and answering any questions within our scope of practice is part of every patient appointment. Education is a huge part of what we do. In cancer nutrition especially, there is so much conflicting information online or shared by friends and family members, that it can be difficult to navigate. Common questions or ‘myths’  that come up frequently were neutropenic diets, sugar ‘feeding’ cancer, soy increasing breast cancer, organic foods being the only ‘safe’ foods, high dose vitamins and herbal supplements can help treat cancer, and the ‘silver lining’ to getting cancer is that you’ll finally lose weight. While none of these are accurate, discussing the information in a compassionate way is critical in rapport building, and patient receptiveness. 

Some patients may not be able to reach all of their nutrition needs from oral intake. This can be for many different reasons, and many different types of cancer. Part of our job as oncology dietitians is to monitor nutrition status, and make recommendations to the medical and surgical oncologists about considering nutrition support. Nutrition support is a way to reach nutrition needs via alternate routes. There is enteral nutrition, which uses tubes that bypass certain parts of the digestive track to feed, most commonly referred to feeding tubes or tube feeding. For example, if you have a head and neck cancer, and during radiation you aren’t able to eat or drink enough due to side effects from radiation, we may recommend a feeding tube to your stomach, so your body can get the nutrition it needs, without having to swallow. If this option is medically and anatomically not feasible, we can consider parenteral nutrition, which is more commonly referred to as ‘IV nutrition.’ This requires an IV, usually a central line, to feed nutrients through an IV several hours every day or around the clock. This is reserved for times when the digestive tract is not functioning enough to use enteral nutrition. As oncology dietitians, we help initiate and manage nutrition support for our patients to ensure they can meet their nutrition needs. 

While we are oncology dietitians and specialize in cancer nutrition, rarely do patients have zero other health conditions. When feasible and appropriate with the priorities of care, we also address other conditions that impact nutrition like diabetes, hypertension, cardiovascular disease, chronic kidney disease, and more.

In Conclusion

If you’ve made it this far, I hope you learned more about cancer nutrition and the role of oncology dietitians. Please do not hesitate to ask questions in the comments, or ask to learn more about something I shared in this post.

If you or someone you love has cancer, and you are looking for an oncology dietitian to work with you, I recommend asking your oncologist if they have a dietitian on staff they can refer you to. I am not currently taking private clients at this time, but I’d be happy to help you find someone near you. 

Below are some evidenced-based resources on cancer nutrition:

https://www.aicr.org

https://www.cancer.org/cancer/survivorship/coping/nutrition.html

https://www.oncologynutrition.org/erfc