Interview with an Expert: Nutrition Update for Patients with Pancreatic Cancer
Topic: Precision Medicine
Charles S. Fuchs, M.D., MPH, is the Director of the Yale Cancer Center and the Physician-in-Chief of the Smilow Cancer Hospital. In this interview, he discusses why proper nutrition is important for patients with pancreatic cancer.
What is the main function of the pancreas and how does pancreatic cancer impact how the pancreas works?
The pancreas is responsible for aiding in digestion. When patients have pancreatic cancer, they may not have sufficient pancreatic enzymes being manufactured to help with digestion, or these enzymes are not getting into the intestinal tract. When that happens, doctors might recommend pills containing supplemental enzymes to improve digestion and make up for enzyme deficiencies that might occur as a result of having cancer. These issues can be caused by surgery for pancreatic cancer or by pancreatic function being diminished as a result of having pancreatic cancer.
In addition to aiding in digestion, the pancreas produces insulin and releases it into the bloodstream to control blood sugar. Adults with diabetes make a fair amount of insulin, but are typically insulin-resistant. That is, their bodies produce large amounts of insulin, but cannot make use of it, which creates high levels in the blood. High levels of insulin are thought to be a risk factor for pancreatic cancer. There are even rare cases where people may be diagnosed with diabetes in mid-life and it’s actually because they have undiagnosed pancreatic cancer.
Are there certain foods that may impact the risk for pancreatic cancer?
Foods with a high glycemic load, meaning that they are high in substances that increase blood sugar, may be linked to an increased risk for pancreatic cancer. Obesity is a major driver of the disease, and a sedentary lifestyle is also a factor. I recommend following a healthful diet and exercising regularly.
My research published in The New England Journal of Medicine (November 21, 2013) followed more than 118,000 healthy volunteers over three decades to assess their nut consumption and found that people who ate at least one ounce of nuts a minimum of seven times per week had a 20% lower death rate and fewer deaths due to cancer, heart disease and respiratory disease. Results also revealed that eating a one-ounce serving of nuts at least twice per week was associated with a lower risk of pancreatic cancer in women.
What is the latest research on the link between obesity and pancreatic cancer?
The number one cause of Type II diabetes, which impacts approximately 8% of Americans, is obesity. People with Type II diabetes are at an increased risk of developing pancreatic cancer. Obesity makes people insulin resistant, meaning that they have to make significantly more insulin than what is typically needed to control their blood sugar.
Why is it so important for pancreatic cancer patients to focus on proper nutrition?
Studies have shown that 75% of newly diagnosed cancer patients believe that there is a diet, food or supplement that can positively improve their outcome. Our recent studies of newly diagnosed cancer patients suggest that regular exercise and a balanced diet that avoids excessive carbohydrates can improve patient survival. Moreover, through proper nutrition, patients can maintain their muscle mass, which will help them perform activities of daily living, stay on a treatment plan, and improve overall quality of life.
What are some suggestions you have for patients who are trying to optimize their nutrition during treatment? For example, which foods should be avoided, and which foods are considered more nourishing and digestible and should be eaten as often as possible?
Pancreatic cancer patients who have difficulty consuming larger meals should try to eat 5-6 small meals or snacks throughout the day, as eating smaller amounts is easier for the body to digest and absorb and can minimize nausea. Patients should also eat foods that contain healthy fat and avoid greasy, fried foods. Eat as many fruits, vegetables, whole grains and lean proteins as possible and avoid excess sugar and sweets. Drink plenty of fluids to avoid dehydration and exercise frequently – even if it is just a short walk. For patients who are underweight, gaining or maintaining current weight is critical, so I recommend relaxing restrictions on low-cholesterol and low-fat foods. Otherwise, for patients with a relatively stable or healthy weight, maintaining weight with a balanced diet is preferred.
What do you advise patients who complain of a loss of appetite and problems digesting food?
This is a complex issue, as these problems can result from a physical problem in digestion related to pancreatic enzymes, or a deficiency in these enzymes. It could also reflect that the cancer is affecting the gastrointestinal tract in other ways, reducing the patient’s appetite. Additionally, pancreatic cancer can cause poor appetite, independent of these other factors.
Moreover, chemotherapy and recovery after surgery can both impair appetite. Patients should speak with their physicians if they are experiencing these problems while they’re going through treatment. Major medical centers typically have nutritionists on staff, and a nutritional consultation is invaluable. The goal is for each patient to remain as healthy as possible during treatment, and proper nutrition is key to making that happen.
What is the difference between malabsorption and cachexia (a condition characterized by progressive muscle wasting, loss of appetite, and unintentional weight loss)? How can cachexia be managed?
Pancreatic cancer has a unique ability to manipulate and rely on metabolic pathways and contribute to cachexia, which is a common condition in cancer patients that causes muscle wasting, loss of appetite, and unintentional weight loss. Cachexia occurs more often in pancreatic cancer patients than in patients suffering from other types of cancer.
In our current research, we have been measuring the blood from seemingly healthy patients who show no outward signs or symptoms of cancer, and we are finding pancreatic cancer signals in the blood years before patients exhibit any disease signs or symptoms. These patients’ metabolic screens are showing that they are subtly losing muscle. Moreover, our research team has confirmed this finding in mouse models. This breaking down of a muscle is an early sign of cachexia. We are trying to understand in both animal models and in our patient population which chemicals the pancreatic cancer is producing to cause cachexia and which chemicals the cancer is relying on for its survival so that we can block them. We can show biochemical evidence of muscle breakdown five years before people even know they have pancreatic cancer. Additional research is underway.
Patients showing signs of cachexia may benefit from appetite stimulants, omega-3 fatty acids, and/or other nutritional supplements. Cachexic patients would definitely benefit from working with a nutritionist to develop a customized nutritional plan.
Cachexia is very different from malabsorption, which occurs when a patient is actually taking food in but the nutrients are not being absorbed and are instead coming out in the stool. Malabsorption occurs when the pancreas does not make enough enzymes so patients can’t process the nutrients in their gastrointestinal tract, so that nutrients do not get absorbed. As a result, people will experience weight loss and sometimes diarrhea.
What dietary problems can some patients experience as a result of surgery? How quickly can most patients, if they do have surgery, resume a normal diet?
Patients should follow diet recommendations from their doctors. They will gradually resume a normal diet in terms of quantity of calorie consumption and dietary quality and variety. Following a Whipple procedure, which involves the surgical removal of part of the small intestine, pancreas and sometimes part of the stomach, patients should eat small, frequent meals; avoid high fat, high sugar and high fiber foods; eat foods high in protein to encourage healing; and limit liquid intake during meals, as significant liquid intake may impact how much food can be eaten.
What dietary problems can some patients experience when they’re going through chemotherapy and radiation?
The most common complaints are diminished appetite (sometimes related to nausea), complete loss of appetite, and change in taste. Luckily, these are all treatable. Typically, though, there’s not a clear rule of thumb for which foods patients can and can’t tolerate during treatment, as it varies from person to person.
Is vitamin D important for pancreatic cancer patients? Can patients benefit from eating food rich in vitamin D as well as from taking vitamin D supplements? Have there been any recent clinical studies that have demonstrated that taking vitamin D resulted in improved survival or a decrease in tumor size?
Vitamin D actually changes which genes are turned on and turned off, which then affects cancer development. Whereas other vitamins only impact simple metabolic pathways, vitamin D is technically really a hormone. The cell takes it into the nucleus and it affects the way we manage our DNA. It also changes which genes are overproduced.
Research into the potential benefit of vitamin D is extremely promising. Studies have found that people with higher levels of vitamin D have a lower risk of developing pancreatic cancer and that in people who already have the disease, people with higher levels of vitamin D have better outcomes.
In fact, The Wall Street Journal recently featured an article about how doctors, scientists and other experts are coming together to find breakthroughs for pancreatic cancer. One of the most exciting areas is the Lustgarten Foundation’s research with a synthetic form of vitamin D, which shuts down the stromal cells that surround the tumor and nurture the cancer cells. By shutting down the activity of the stromal cells, treatment is more effective.
Ronald Evans, Ph.D., of the Salk Institute for Biological Studies and a Lustgarten Foundation Distinguished Scholar, found that a synthetic derivative of vitamin D could potentially delay pancreatic cancer tumor growth when combined with chemotherapy in mice, resulting in a 57 percent increase in lifespan compared to chemotherapy alone. He is now conducting research to determine if late stage pancreatic cancer patients’ tumors have a vitamin D receptor in their metastases as well, which would make them eligible for treatment with synthetic vitamin D as part of their therapy.
Can pancreatic cancer patients benefit from increasing their consumption of foods/supplements containing vitamin A and vitamin C?
There’s no evidence that I know of that either vitamin A or vitamin C or any of the other vitamins influence pancreatic cancer development. The work with vitamin D is ongoing and there’s no harm in taking a vitamin D supplement.
Does pancreatic cancer deplete the body of certain nutrients, and how can these nutrients be replaced by supplements, including pancreatic enzyme supplements? How do these supplements work?
There’s not any particular nutrient that is affected more than another. Pancreatic enzyme supplements contain the pancreatic enzymes lipase, amylase and protease which help in the digestion of fat, carbohydrates and proteins. These enzymes may be needed if there is a blockage in the pancreatic duct or removal of part of the pancreas, which can cause a change in the amount and the flow of pancreatic juice. This juice contains enzymes that aid in digestion. There is a titration of these enzymes that can be very helpful, so that you can determine what concentration of each enzyme is necessary for each meal and snack. These supplements are available in both over-the-counter and prescription forms.
What advice would you give to pancreatic cancer patients who are searching for information on the diet that would be most appropriate for them during treatment?
Patients should speak with their physicians to determine what’s best for them and to identify reliable sources of information online that they can refer to for guidance. It’s alright if a physician says that he or she doesn’t have the answers but will connect you with a nutritionist who has more expertise. Speaking about nutrition is not necessarily common during oncology visits, as the conversation typically revolves around treatment plans. However, it is a very important topic, and patients should feel comfortable asking questions about how to optimize nutrition during treatment and advocating for a referral to a nutritionist.
What role does a nutritionist play in helping pancreatic cancer patients eat a well-balanced diet? When in the process should a patient seek out the help of a nutritionist?
The nutritionist is the best resource I have for when a patient asks, “What can I do to help myself?” Patients should speak with a nutritionist if they are experiencing side effects during treatment or after surgery that might require a change in diet. Nutritionists are also extremely helpful when there is continued weight loss without correction and there is no underlying medical reason for this. A nutritionist can create a customized eating plan that is specific to a particular patient and that takes into account the impact pancreatic cancer treatment has on digestion.
Ask the Nutritionist: Stephanie Meyers, M.S., R.D./L.D.N., C.N.S.D.
Stephanie Meyers, M.S., R.D./L.D.N., C.N.S.D., is a Senior Clinical Nutritionist/Registered Dietitian at The Dana-Farber Cancer Institute in Boston. She works in conjunction with the Leonard P. Zakim Center for Integrated Therapies, where she specializes in the nutritional care of cancer patients. Stephanie is also an adjunct faculty member in the Department of Nutrition at Boston University.
As a pancreatic cancer patient, you may face unique challenges to maintaining a balanced diet during treatment. You could experience unintentional weight changes, or you might find that despite a concerted effort to eat well, you are losing weight and muscle mass, or you may have less energy for activities of daily living. There isn’t a “one size fits all” diet for pancreatic cancer patients; a tailored approach is necessary. Nutritionists will help you develop a customized plan to take control of your diet and ensure you’re eating the best that you can – an empowering step towards optimizing your health and energy and minimizing treatment side effects.
There are calculations that nutritionists use to determine the number of calories, grams of protein and ounces of fluid needed per day. Once these amounts have been met, you know you don’t have to eat or drink anything else that day, and your caregivers can feel confident that you have received proper nourishment.
Below are some common issues encountered during treatment and some strategies for addressing them. Please note that the following information should not be used as a substitute for personal nutrition information from your registered dietitian or physician.
COPING WITH NAUSEA:
- Eat small, frequent meals. Research has demonstrated that giving smaller food portions more frequently actually results in better oral intake than when given a plate of food with a pre-treatment sized portion on it. Eat from salad or dessert plates.
- Eat foods known to be beneficial for quelling nausea, including ginger and lemon (fresh, grated, or as an ingredient in other foods). In fact, even smelling a wedge of lemon has been shown to help with nausea; this is especially helpful when you’re out at a restaurant with family or friends.
- Eat high sodium foods that are coupled with potassium, such as a saltine cracker and a potato chip. Eating four or five dry, crunchy items is sometimes enough to settle gastric acid secretions in the stomach so you then feel well enough to have other more nutritious food options, such as a sandwich or soup.
- Eat cold foods.
- Avoid foods with a strong smell or odor.
COPING WITH CONSTIPATION:
- Take stool softeners or laxatives as recommended by your physician.
- Increase fiber intake via fresh fruits (including apples and berries) and vegetables (such as broccoli and salad), whole grains, nuts and seeds.
- Assure adequate fluid intake.
MANAGING YOUR DIET FOLLOWING A WHIPPLE PROCEDURE:
- Eat small, frequent meals which include lean, high-quality protein, such as chicken or fish that is easy to digest.
- Limit intake of foods high in fat and sugar simultaneously to prevent dumping syndrome, which is the rapid movement of food from the stomach into the small intestine, which could result in discomfort. A nutritionist will be able to calculate exactly how many grams of fat and sugar you can eat and how they should be spread out over the day.
COPING WITH DIARRHEA:
- Take an anti-diarrhea medication as recommended by your physician.
- Follow a low-fiber, low-residue diet to limit foods that add residue, or undigested food, to the stool.
- Following the diet below should help control symptoms such as stomach cramping, bloating, gas and diarrhea:
- Minimize consumption of raw fruits and vegetables, nuts, whole grain breads and cereals, seeds, and cooked or canned fruits and vegetables with seeds.
- Eat white bread, plain crackers, cooked cereals, cold cereals, white rice, noodles and pasta, and cooked or canned fruits and vegetables without seeds (such as bananas, avocados, cooked potatoes without the skin, green beans, carrots and mushrooms)li>
- Eat vegetables that contain predominantly soluble fiber, like asparagus, that are better tolerated than vegetables like broccoli.
COPING WITH CACHEXIA (MUSCLE WASTING)
- Consider supplementation with anabolic steroids, appetite stimulants, omega-3 fatty acid and other nutritional supplements and certain medications.
- Exercise if possible to increase appetite and help slow down the decline in muscle mass.
- Eat small, frequent meals that are high in calories.
FINDING A NUTRITIONIST:
No matter what type of pancreatic cancer treatment you are receiving, it can be helpful to meet on a regular basis with a nutritionist. I follow a “chairside approach,” where I will consult with my patients while they’re in their infusion chairs receiving chemotherapy or hydration treatment.
This way, we can discuss which dietary modifications have and haven’t worked to manage and minimize symptoms. We can also strategize a new approach, as so much of nutrition is trial and error to develop an individualized plan.
In environments where oncologists have access to trained nutritionists who specialize in oncology, there is more recognition that there is a real benefit both in a quality of life standpoint and also potentially in terms of helping patients tolerate treatment better. You can also visit www.eatright.org,the website of the Academy of Nutrition and Dietetics, and search for a certified specialist in cancer/oncology nutrition by entering your zip code under the Find an Expert link.
Make a difference in patients’ lives by donating to the Lustgarten Foundation today and supporting pancreatic cancer research. We couldn’t accomplish all that we do without you.