Omega-3 fatty acids are special unsaturated fats our bodies need for optimum health. Unfortunately, most Americans are deficient in omega-3s, and as a result are more likely to develop cardiovascular disease, cancer, inflammatory disorders, and mental and emotional problems. Eating foods rich in omega-3s can reduce these risks and also help treat depression, bipolar disorder, autism, and attention deficit hyperactivity disorder.
I don’t think there is any practical way to measure your omega-3 levels. If there were, and if they were low, the solution would be to do what you should do anyway: increase your intake. Instead of worrying about what your levels are, try to calculate how much omega-3s your diet provides. These fatty acids are found principally in oily fish that live in cold water, primarily wild salmon, mackerel, herring, and sardines. Bluefish is also rich in omega-3s as is - to a lesser extent - albacore tuna, but both of these tasty fish are contaminated by mercury and should be avoided. Other dietary sources of omega-3s include walnuts, flaxseeds and hemp seeds - and the oils extracted from them.