Here's something fatty you should be eating twice a week: fish.

Oily fishes – salmon, mackerel, tuna, halibut, sardines, anchovies – are rich in omega-3s, a jack-of-all-trades nutrient for heart and brain health.

Omega-3s are an essential fatty acid, which the body can't produce naturally but needs for proper functioning. At the cellular level, omega-3s help cell membranes remain flexible, allowing for the easy in-and-out flow of nutrition and waste. In addition, these healthy fats reduce inflammation and cholesterol, control blood clotting and aid in the transmission of brain signals.

The omega-3s in fish and fish oil are different from the fatty acids found in plant sources such as vegetable oils, flax seeds and walnuts, known as alpha-linolenic acid (ALA). Fish fatty acids – eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – have the most evidence of health benefits. The body can convert ALA acids to small amounts of EPA and DHA, according to The Nutrition Source, a website of the Harvard School of Public Health.

Fish-oil supplements are a popular alternative for omega-3s, but the science is still unclear on whether they are a substitute for eating oily fish. An analysis published in the April 9 issue of the Archives of Internal Medicine showed that taking fish-oil pills had no benefit for heart attack and stroke survivors.

It's best to get the nutrients directly from natural foods, said Janet Brancato, a registered dietitian at Valley Hospital Health Systems in Paramus. "We always recommend food first. Talk to your doctor if you're going to take a supplement because it may interact with drugs you're taking," she said.

Food manufacturers have jumped on the recent omega-3 buzz by fortifying their products with the nutrient. Walk down the supermarket aisle and you can see orange juice, milk, yogurt, cereal and eggs all boasting "omega-3 fortified" labels.

Experts stress the importance of regulating the balance in your body between omega-3 and omega-6 fatty acids. Western diets tend to have a surplus of omega-6, which is found in safflower, sunflower, corn and soybean oils and most processed foods. "It's more of trying to get a better balance, not just to get omega-3. You want to lower omega-6 in the cells. They tend to work in opposite directions," said Brancato.

An easy way to boost the omega-3s in your diet is to switch to canola oil and eat two 3.5 ounce servings of fatty fish a week, said Brancato. Grass-fed beef is also a source of these fatty acids.

To help regulate her cholesterol, Brancato said she takes a daily fish-oil pill. "I love fish but I don't get to have it every week. It's sort of like a supplement that fills in," she said.

So is it helping? "It's part of a whole lifestyle – diet and exercise. It's not one particular thing," she said.

Email: fujimori@northjersey.com