Eating oily fish could reduce the risk of death among people with bowel cancer, a new study has found.
Researchers said patients with bowel cancer might benefit from boosting their intake of omega 3 fatty acids, which are found in oily fish such as salmon and mackerel.
In the study, increasing intake of omega 3 from oily fish by at least 0.15g daily after diagnosis was associated with a 70% lower risk of dying from bowel cancer.
Bowel cancer is one of the most common types of cancer diagnosed in the UK, with around 40,000 new cases diagnosed every year.
Previous studies have shown that omega 3 polyunsaturated fatty acids (PUFAs) can suppress tumour growth and prevent blood supply to malignant cells.
For the research, published online in the journal Gut, experts analysed data from two long term studies: the Nurses’ Health Study of 121,700 female nurses and the Health Professionals Follow Up Study of 51, 529 male health professionals.
All participants filled in questionnaires about their medical history and lifestyle factors when they joined the studies, and this was repeated every two years subsequently.
The information requested included any diagnosis of bowel cancer and other potentially influential factors such as height, weight, smoking status, regular use of aspirin and non-steroidal inflammatory drugs, and exercise taken.
Data on what they ate was collected and updated every four years, with categories for each nutrient ranging from “never or less than once a month” to “six or more times a day”.
Among 1,659 participants who developed bowel cancer during the course of the studies, 561 died.
Of these, 169 were classified as deaths caused by the disease. Other major causes of death included cardiovascular disease and other types of cancer.
Participants with a high intake of omega 3 from oily fish were more likely to be physically active, take multivitamins, drink alcohol and to consume more vitamin D and fibre. They were also less likely to smoke – all factors associated with a lower risk of bowel cancer.
Those who had been diagnosed with bowel cancer and whose diets contained higher levels of omega 3 from oily fish had a lower risk of dying from the disease.
Omega 3 intake, however, was not linked to a lower risk of death overall.
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Compared with patients who consumed less than 0.1g of omega 3 fatty acids daily, those who consumed at least 0.3g daily after their diagnosis had a 41% lower risk of dying from their disease.
The association between marine omega 3 intake and lowered risk of death seemed to be particularly evident among those who were tall, had a BMI below 25 or who didn’t take regular aspirin.
Increasing intake of marine omega 3 by at least 0.15 g daily after diagnosis was associated with a 70% lower risk of dying from bowel cancer; while a reduction in daily intake was associated with a 10% heightened risk of death from the disease.
“If replicated by other studies, our results support the clinical recommendation of increasing marine omega 3 PUFAs among patients with bowel cancer,” researchers concluded.