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Getting Ready for Chemotherapy

By: Julie Bosworth, RD, LDN

The days following a cancer diagnosis can be the most anxiety-provoking time period in someone’s life. There are many unknowns, and patients face treatments and procedures that are unfamiliar to them.

Patients may feel out of control due to the newness of chemotherapy, medications, and terminology to which they have never been exposed. They wonder how they are going to handle treatment and if they are going experience side-effects. The good news is that focusing on nutrition can help to bridge the gap of unfamiliarity as chemotherapy treatment approaches.

Adequate hydration and healthy eating builds our bodies with every sip and bite! Subsequently, hydrating and eating well are important patterns to establish before chemotherapy begins.

What can patients do to support their nutritional status in the days leading up to treatment? What do dietitians mean by adequate hydration and healthy eating?

Fluid sets the tone for chemotherapy to go well, with minimal side effects. It bathes the cells and removes the byproducts of cellular respiration, flushes chemotherapy through the body, and provides an environment for calories and protein to support the rebuilding of red and white blood cells. Cell regrowth is essential to keeping treatment on schedule.

Most people do not understand how much fluid, not just water, their bodies need to function optimally. Fluid is anything that would be liquid if allowed to sit at room temperature. The standard “64 ounces per day of fluid” may be grossly-inadequate for people who weigh more than 141 pounds, or are obese.

In addition, waiting for thirst to trigger drinking cannot be relied upon, because as we age our thirst sensors on our tongues decrease, with thirst lagging behind actual fluid need up to 40%. Therefore, the result can be that we are a liter of fluid below our needs by the time we sense thirst, resulting in dehydration.

Dehydration impacts several side-effects associated with chemotherapy. It increases chemotherapy and heightens side-effects, causes nausea, fatigue, and taste changes and increases likelihood of constipation. It is often difficult to separate the effects of chemotherapy from symptoms of dehydration, as you can see. Therefore, getting adequately hydrated before and staying hydrated through treatment can head off many unpleasant side effects.

An easy way to calculate fluid needs is:
Weight in pounds / 2.2 = Weight in kilos = ounces of fluid needed per day

An easier way is to ask a registered dietitian to assist you in the calculation, or to calculate your goal for you if you think you may be over 120% ideal body weight.

It is also helpful to include two to three sources (8 ounces each) of fluids that have sodium, such as broth, milk, Gatorade, Powerade, or even soup. The sodium acts like a sponge and helps pull the fluid into the body so you will benefit from it more and not flush the sodium out of your body. Even IV fluid has sodium, so there is no concern about a small amount of sodium in your fluid intake. It is both necessary and helpful to prevent dehydration.

The next thing to do to prepare for chemotherapy is to eat CALORIES IN SMALL MEALS OR LARGE SNACKS, FIVE TO SIX TIMES PER DAY. Because you need more calories to support your current weight throughout treatment, not to make you gain weight, frequent eating supports that higher calorie need. Getting in the habit of this eating pattern helps to get you used to eating more often. It is also beneficial to avoid higher fat foods leading up to treatment, as they can also slow digestion and add to symptoms around treatment.

In addition to assisting getting adequate calories, this eating pattern also fosters better bowel regularity. Constipation is a familiar and unpleasant side-effect of the medications to prevent nausea which are provided around the time of chemotherapy. As a result the intestines slow down and constipation is common. Smaller amounts of food traveling through to be processed work better than three large meals. If you are already plagued with constipation as your regular bowel pattern, please discuss this with your dietitian, nurse or doctor prior to starting treatment.

Lastly, INCLUDING A PROTEIN SOURCE AT ALL MEALS AND SNACKS is the easiest way to meet elevated needs for protein during treatment. Calories support protein, which supports the rebuilding and regrowth of cells between treatments. It is another good habit to include protein before starting treatment. Ask yourself prior to eating, “where is the protein on my plate?” This simple step is often adequate in covering the difference between regular needs for protein and those needs during treatment.

Establishing treatment eating patterns in the weeks and days leading up to chemotherapy treatment can make eating once treatment has started just that much easier. Food then becomes second-nature and it is easier to comply with hydration, and focusing on adequate calories and protein through frequent eating. Once established as a habit, these patterns carry throughout chemotherapy and will allow for the best outcomes and prevent fatigue.

One last step in preparing for chemotherapy is to INCLUDE 5-10 SERVINGS OF FRUITS AND VEGETABLES DAILY. Fruits and vegetables and the simple and expected flavor are most appealing during treatment, work well in the setting of taste changes, and help prevent constipation. A serving is considered to be a 1/2 cup, except for melon chunks, berries and greens which are 1 cup each. In addition, fruits and vegetables build immunity and work with treatment to fight cancer. The more colors included, the better! Put a rainbow on your plate!

Adequate fluids, and frequent healthy eating is the defense against chemotherapy. Food powers you through treatment, rebuilding your body. You may have lost weight leading up to your diagnosis; taking advantage of the days and weeks leading up to the start of chemotherapy can place you in a better position to receive treatment. It can also prevent many of the side-effects, including fatigue and constipation, once treatment begins.