For cancer patients, taking fish oil supplements could help maintain and even regain lost muscle mass, according to a new study.
Most patients who took a daily supplement of fish oil for 10 weeks either maintained or gained muscle mass, whereas patients who didn't take anything either maintained or lost muscle mass, the study said.
"Muscle loss in cancer is partly due to the presence of inflammation," which causes a breakdown in muscle mass, said study researcher Vera Mazurak, of the University of Alberta in Canada.
But fish oils interfere with inflammation, thereby reducing its effect on muscle, Mazurak said. Loss of muscle mass and fat is bad for cancer patients because it hampers their ability to respond to cancer treatments, she said.
The study was published online Feb. 27 in the journal Cancer.
Fish oil findings
Mazurak and her colleagues asked 16 patients with non-small cell lung cancer to take a 2.2-gram supplement of eicosapentaenoic acid, a compound in fish oil, once a day during their 10-week chemotherapy treatments. The researchers did not give the supplements to 24 other cancer patients also in the study.
The researchers measured the patients' weight, blood levels of eicosapentaenoic acid , and checked their muscle and fat composition using computed tomography images throughout the study period.
Patients who didn't take any fish oil lost an average of 5.1 pounds (2.3 kilograms) over the 10 weeks, but patients who took the fish oil maintained their weight throughout the study, researchers said.
And the patients who had the highest concentration of eicosapentaenoic acid in their blood during the study period gained the most muscle mass, the study said.
Sixty-nine percent of patients who took fish oil either gained or maintained muscle mass, but 29 percent of people who didn't take the supplement gained or maintained muscle mass, the study said.
There were no differences between the groups in terms of the amount of fat tissue in their bodies over the study, researchers said.
Weight loss and survival
Maintaining a healthy body weight is integral to cancer patients' survival, Mazurak said. Wasting syndrome is common in end-stage cancer patients and results in loss of weight, muscle mass and appetite.
Patients with healthy body weights do better in therapy, have a better quality of life and have better prognoses than those who are not well nourished, she said.
Mazurak said she plans to confirm the results in a larger group of patients, as well as to see if fish oil benefits patients with other types of cancers.
Past studies have also shown a link between fish oil and cancer patients' appetites . One study, published in 1999 in the British Journal of Cancer, showed that taking a fish oil supplement improved the appetites of all 20 advanced pancreatic cancer patients involved in the study.
Pass it on: Fish oil can help cancer patients maintain and gain muscle mass during their chemotherapy treatments.
Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.
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