But, experts say a healthy diet can make the process a little easier.
"You want to try and eat as healthy of a diet as you can, and be as active as you can," said Valerie Steensen, registered dietitian.
Steensen is a dietitian at Heartland's Cancer Center. She works with most of the cancer patients, helping to manage side effects and deter feelings of discomfort based on a balanced diet.
"I talk to them to see what kind of issues they're having, if they're having nausea, vomiting, or diarrhea, and I help them make better food choices," said Steensen.
John Owens is one of her patients. He's been living with prostate cancer for two years, and as he's finishing up his regular radiation treatments, Steensen advises him on proper nutrition to keep him healthy.
"Well, I eat a lot of rice, chicken and fish, and that settles my stomach better," said John Owens, cancer patient.
"It all depends on their treatment regimen," said Steensen.
In certain cases, like colorectal cancer, good nutrition choices can make all the difference.
"It would be in your large intestine, and it is largely affected by your nutrition and poor nutrition can definitely increase your risk of colon cancer," said Steensen.
Steensen often recommends 5 or 6 small meals a day with plenty of fruits, vegetables and whole grains, and not too much red and processed meats, while keeping a healthy weight.
"The more overweight you are, then the more at risk you are. The healthier your nutrition is, then the more likely you are to prevent something like this," said Steensen.
"I feel very fortunate that they know what to do here and they've got everything under control," said Owens.
Cancer and cancer treatments can affect appetite and the body's ability to absorb nutrients.
Dietitians say making the right food choices can help patients feel better and stronger.
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