The study was conducted by a team of researchers from the University of Manchester and funded by the Association for International Cancer Research, and examined the effect of taking omega-3 on 79 healthy participants.
Findings of the study, published in The American Journal of Clinical Nutrition, revealed that consuming regular doses of fish oils increases immunity to sunlight.
It directly decreases sunlight-induced immunity suppression - called immunosuppression - which affects the body's power to combat skin cancer and infection.
Professor Lesley Rhodes, Professor of Experimental Dermatology from the Photobiology Unit Dermatology Centre at the University's School of Medicine and Salford Royal NHS Foundation Trust, said their study was the first of its kind conducted using humans:
"There has been research in this area carried out on mice in the past but this is the first time that there has been a clinical trial directly in people. It has taken a number of years to get to this stage and the findings are very exciting. This study adds to the evidence that omega-3 is a potential nutrient to protect against skin cancer. Although the changes we found when someone took the oil were small, they suggest that a continuous low level of chemoprevention from taking omega-3 could reduce the risk of skin cancer over an individual's lifetime."
The volunteers consumed a 4g dose of omega-3 - approximately one and a half portions of oily fish each day. Then they were exposed to either 8, 15, or 30 minutes of summer midday sun in Manchester using a specific light machine.
A number of other participants took a placebo before being exposed to the sunlight machine.
Immunosuppression was shown to be 50 percent lower in the subjects that took the omega-3 and were exposed to 8 and 15 minutes of sunshine compared with the volunteers who did not take the supplement. Little to no impact on those in the 30 minute group was shown.
The conclusions from this study are significant in the battle against skin cancer, because earlier studies have always shown that sunscreens are frequently applied incorrectly and only worn on vacation.
However, Professor Rhodes points out omega-3 is not a substitute for suntan lotion or physical protection, and that it should be seen as additional protection factor to help keep the skin from burning.
Historically, fish oil has already been associated with health benefits like protecting against cardiovascular disease, helping prevent age-related vision loss, and even slowing the growth of prostate cancer cells.
Professor Rhodes and her team of investigators will continue with their research with more omega-3 studies being conducted on healthy humans at Salford Royal.
Nearly 100,000 cases of non-melanoma skin cancer were diagnosed in the United Kingdom in 2010, proving that it is a quite common cancer.
Dr Helen Rippon, Head of Science at AICR, said:
"Skin cancer has been one of the fastest growing types of cancer, and numbers will likely continue to increase. It is always exciting to see research that AIRC has funded generating such promising results, and we look forward to seeing future developments in this area."
Written by Kelly Fitzgerald