Eating foods rich in omega-3 fatty acids such as oily fish may help to prevent the spread of prostate cancer, scientists said on Tuesday.
Omega-3 and omega-6 are essential fatty acids that work together to promote good health. The body cannot make them, so eating a diet rich in the substances is important.
Fish and certain oils such as canola and flaxseed are sources of omega-3 while raw nuts and seeds contain omega-6.
In laboratory studies, scientists at the Paterson Institute at the Christie Hospital in Manchester, England found that omega-3 fats could block the spread of cancerous cells.
Dr Mick Brown, chief scientist in the research group, said the results of the research published in the British Journal of Cancer suggest a diet rich in omega-3 fatty acids might help to inhibit the spread of the disease in men with early prostate cancer.
Because omega-3 and omega-6 work together, it is important to maintain a balance of the two for good health.
“Omega-6 fats, found in vegetable oils, nuts and seeds, increased the spread of tumor cells into bone marrow. This invasion was blocked by omega 3 fats -- the ones found in oily fish,” Brown said in a statement.
“It is possible to have a healthy balance of these two types of fat — we only need about half as much omega-3 as omega-6 — that will still stop cancer cells from spreading,” he added.
The researchers believe omega-3 fatty acids interfere with functions of omega-6, which cancer cells may use as a source of energy, and prevent them from spreading beyond the prostate gland.
Prostate cancer is more treatable and has a better survival rate if it is diagnosed and treated in its earliest stages.
“Some tumors develop slowly in the prostate without producing symptoms and sometimes when symptoms do develop, it is because the cancer has already spread.
“Eating a diet with the right balance of omega-3 and omega-6 fats may well help to keep prostate cancer within the prostate gland where it may be monitored safely or more easily treated with surgery or radiotherapy,” said Noel Clarke, a co-author of the study.
Prostate cancer is the third most common cancer in men worldwide with 543,000 new cases each year, according to the International Agency for Research on Cancer (IARC) in Lyon, France.
Professor John Toy, medical director of the charity Cancer Research UK which publishes the journal, said the role of diet in prostate cancer is not fully clear and that more studies were needed.
“Cancer Research UK advises people to reduce their risk of cancer by eating a healthy diet, high in fiber, fruit and vegetables and low in red and processed meat,” Toy said.