There seems to be no end to the benefits of fish oils. Not only are they said to boost heart, brain and joint health, but they also prevent cancer, eye disease and bone problems.
Last week, a new study suggested they could assist the body against premature ageing. But how do you separate the facts from the hype?
WHAT'S SO SPECIAL ABOUT FISH OILS?
Fish oils are a type of polyunsaturated fat - a 'healthy' fat. Unlike saturated animal fats, they don't raise your cholesterol levels, but are known to have a positive effect on health. Polyunsaturated fats are divided into two groups of what are called Essential Fatty Acids (or EFAs) - omega-3 and omega-6.
Both omegas are essential in helping to regulate blood clotting, body temperature, blood pressure and the immune system; they are also needed to make prostaglandins, important hormone-like chemicals in the body. The only way we can get them is through our diet.
Omega-3 has particular benefits, producing vital substances such as DHA (docosahexaenoic acid), thought to play a key role in the development of brain and cognitive function, and EPA ( eicosapentaenoic acid), vital for brain health.
The richest source of omega-3s are fish oils - salmon, mackerel, fresh tuna and herring.
While most Britons consume more than enough omega-6 oils (found in most edible oils, but particularly sunflower and corn, as well as meat), they are deficient in omega-3.
WILL THEY PROTECT MY HEART?
There have been a number of studies suggesting fish oils boost heart health, but the most compelling evidence was a study last year published in the Journal Of The American College Of Cardiology.
Led by Dr Carl Lavie, of the Ochsner Cardiology Clinic in Louisiana, the study showed omega-3 oils help to prevent blood clotting and regulate or lower blood pressure.
The strongest heart-protective effect is for patients with established cardiovascular disease, the study found.