Eating fish could help prevent middle-age spread. In what will be welcome news for those who are planning to ditch their diet over Christmas, it seems that fish oil can melt away unwanted fat. Research found that omega-3 fats in fish oil turned ‘bad’ fat cells into healthy ones, which specialise in burning off calories. The number of these “good” fat cells starts to fall around middle-age – meaning the finding could be of particular value to those whose waistlines are becoming larger as they grow older. The Japanese research centred around two types of body fat. The troublesome white variety that we are all too familiar with soaks up extra calories and stores them in big bellies, love handles and saddlebag thighs. But adults also have ‘beige’ fat cells, which burn off calories and generate heat. Experiments on mice showed that fish oil transforms white fat cells into beige ones. Study author Teruo Kawada of Kyoto University said, “We knew from previous research that fish oil has tremendous health benefits, including the prevention of fat accumulation. We tested whether fish oil and an increase in beige cells could be related.” The team tracked the weight of mice fed fatty food for four months. When their food was supplemented with fish oil, the mice put on up to 10 percent less weight and up to 25 percent less fat. High doses of DHA and EHA, compounds found in omega-3 oils, were particularly beneficial, according to the journal Scientific Reports. The discovery could help explain why people from nations like Japan, who have fish-rich diets, tend to have exceptionally long lives. The researchers said, “People have long said that food from Japan and the Mediterranean contribute to longevity, but why these cuisines are beneficial was up for debate. Now we have better insight into why that may be.” Omega-3 fats, which are particularly abundant in oily fish such as herring, mackerel and salmon, are already credited with a host of health benefits, from keeping high blood pressure at bay to helping ward off Alzheimer’s disease. The NHS says we should all eat fish twice a week, including one portion of oily fish. However, many of us would rather pop a pill, with health conscious but time-pressed Britons spending around £10million a year on omega-3 supplements. Not everyone agrees that fish oils boost health. Two years ago, US scientists warned of a link between increased levels of omega-3 fats in the blood and increased incidence of prostate cancer. The researchers said that the amount of omega-3 fatty acids in supplements is huge compared with that in fish and advised men, in particular, against taking it in capsule form. Omega-3’s benefits to the heart are also under the microscope, with several recent studies, including two large-scale round-ups, questioning whether the oils really do boost cardiac health.