The findings, published in the current Annals of Surgery, also bolster the argument for retaining dietitians and nutritionists as an integral part of medical teams, rather than cutting back on these positions, according to Reynolds.

The research team selected esophageal cancer surgery for its study, as the operation tends to be very stressful and predictable in its impact. Patients tend to suffer weight loss afterwards and are at risk of developing complications which have to be treated.

However, a randomized controlled trial showed that omega-3 fatty acids, given as part of an oral nutritional supplement, resulted in the preservation of muscle mass in patients undergoing this type of surgery.

The trial was double-blinded in that two groups of patients were selected, one of which had supplements enriched with omega-3 and one which did not. Neither the researchers nor the patients knew which were in which group.

A 240ml drink enriched with omega-3 (2.2g EPA/day) for one group was given twice daily for five days before surgery. The drink was rich in calories and protein (620 calories and 32g protein), and was virtually identical in calorific content among the two groups.

Immediately after surgery, the supplement was given through a feeding tube for 14 days while patients recovered in hospital. Once patients could eat orally again, the research team asked the patients to drink the supplement orally until 21 days post-surgery had passed, and they were ready to go home.

The health benefits of omega-3 fats found naturally in oily fish, such as salmon, herring, mackerel and sardines, are widely known. Food manufacturers have also begun adding omega-3 to foods such as yoghurt, milk, juice, eggs and infant formula, in the light of scientific evidence which suggests that the fatty acids reduce cardiovascular disease risk, alleviate rheumatoid arthritis and are a key nutrient in brain development in babies.

Ryan explained the logic was that if omega-3 has such an array of health benefits, why not give it to cancer patients?

Patients given the standard feed (without omega-3) suffered clinically severe weight loss post-surgery -- losing an average of 4lbs of muscle mass after the operation. By contrast, omega-3 group patients held their weight, including muscle.

Ryan described the results as extraordinary, and Reynolds noted that omega-3-enriched nutrition appeared to prevent loss of muscle mass by reducing the amount of inflammatory markers in the blood which means that the metabolism is not as stressed as it usually is post-surgery. "We also saw that the omega-3 group was less likely to have a fever in the first week post-surgery which points to the ability of omega-3 to suppress inflammation," he said.

"Taking pure EPA/omega-3 supplement as capsules does not work in cancer patients," Ryan warned. "The omega-3 has to be taken as part of a complete nutritional supplement in combination with lots of calories and high-quality protein."

The treatment is cost effective in that the price was just 4 euros more a day compared with standard nutrition without omega-3. It could also save up to 2,000 euros for every post-operative complication avoided, he estimated.

Commenting in an accompanying editorial in the Annals of Surgery, Michael Meguid, State University of New York professor of surgery, described the study findings as a significant step forward. "It should no longer be a surgeon's preference but the standard of expected norm for the practice of elective complex gut cancer surgery," Meguid said.  

From the April 13, 2009, Prepared Foods E-dition