Cancer survivors are at higher risk of health problems throughout their lives.

One way to stay as strong and healthy as possible is to maintain a good diet. But many survivors simply aren’t doing that.

A new study published in the journal Cancer found that cancer survivors eat less fiber and take in more empty calories than people who have never had cancer.

Dr. Fang Fang Zhang, Ph.D., assistant professor at the Friedman School of Nutrition Science and Policy at Tufts University, Boston, led the study.

“Dietary changes that include more fiber, fruit, and vegetables in the diet and less fat, sodium, and added sugar would be important for cancer survivors,” she said.

Figuring out how cancer survivors eat may help doctors provide better nutritional information for their patients.

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Study Shows Where Cancer Survivors Fall Short

The researchers looked at the diets of 1,533 adults who were part of the National Health and Nutrition Examination Survey from 1999 to 2010.

Dr. Zhang told Healthline the study included patients at various intervals from diagnosis. The average was 10.8 years post diagnosis.

The team used the 2010 Dietary Guidelines for Americans created by the Department of Agriculture and the Department of Health and Human Services.

Results were based on a total healthy eating index score of 100. Cancer survivors scored 47.2. Those who never had cancer scored 48.3.

Survivors scored poorly when it came to eating green vegetables and whole grains. They ate less fiber in general.

People who had had cancer consumed less vitamin D (31 percent of the recommended amount). They were low in vitamin E (47 percent), potassium (55 percent), and calcium (73 percent).

Those who had a history of cancer took in more empty calories. They ate more saturated fat (112 percent) and sodium (133 percent).

Survivors who were also active smokers had an even worse diet. So did those with less education. There wasn’t much difference between men and women in the study.

Older survivors had better diets than younger ones.

This may represent a cohort effect, said Zhang.

“It could also be due to a survival advantage,” she said. “Survivors who are older are those who have survived longer since cancer diagnosis. Survivors who have survived longer may have overall better health, including better diets.”

Breast cancer survivors had the highest quality diet. Lung cancer survivors had the lowest.

Zhang said it’s possible that different symptoms and treatment play a role. Associated side effects can impact diet. Factors such as anxiety and depression may also be associated with different cancer diagnoses.

“It is possible that a better diet quality in breast cancer [patients] is due to, at least partly, heightened awareness and supportive atmosphere for breast cancer survivors,” said Zhang. “Therefore, the worse diet quality in survivors of other cancer types highlights the importance of raising awareness and providing supportive atmosphere to improve nutrition for cancer patients other than breast cancer.”

This study didn’t factor in concerns about life expectancy.

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Why Diet Is so Important After Cancer

Zhang said longitudinal studies are needed. That will help researchers understand more about the types of dietary changes cancer patients make.

It’s also important to learn whether positive changes become long-term habits.

“Unfortunately,” said Zhang, “nutrition is not routinely integrated into the delivery of optimal care for cancer patients. Given the poor diet quality we and others found in cancer survivors, and the high chronic disease burden in this population, it is imperative to routinely integrate nutrition intervention to improve the health and well-being of cancer survivors across the care continuum.”

Cancer and cancer treatment are hard on the body.

Surgery, radiation, and chemotherapy can all cause side effects. This is true in the short term and long term. Depending on the type of treatment, survivors may be at increased risk of heart problems, lung problems, or other types of cancer.

A healthy diet can help survivors stay strong and cut the risks of other health problems.

Registered dietitians at Cancer Treatment Centers of America (CTCA) educate patients on the benefits of a plant-based diet at all points throughout treatment.

“We guide our cancer survivors toward this diet and help them meet realistic goals that fit with their lifestyle,” Kristen Trukova, M.S., R.D., L.D.N., C.N.S.C., C.S.O., clinical oncology dietitian at CTCA at Midwestern Regional Medical Center in Illinois, told Healthline.

She offers one reason it may be difficult at first. “Some survivors who struggle to eat during treatment due to nausea, taste changes, or loss of appetite may find food so enjoyable again that it is hard to choose the right portions and foods,” she said.

Trukova noted another recent study of cancer survivors and lifestyle. More than 80 percent didn’t meet the goal of five servings of fruits and vegetables daily.

“This shows that it is critical for all providers working with cancer survivors to provide education and support, to help patients achieve a cancer recurrence-preventive diet,” she said.

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