Just when you thought your dietary supplement recipe had been perfected with a multivitamin, a dash of calcium, and maybe a twist of glucosamine, there’s a new buzzword in nutrition: omega-3 fatty acids. But what exactly is omega-3? What does heart disease have to do with it? And did someone say “fish burps”?

Elisabetta Politi, RD, nutrition manager of the Duke Diet & Fitness Center, walked us through the oily world of omega-3:

Three of a Kind

In terms of nutrition, omega-3 describes a family of fatty acids: ALA, EPA, and DHA. ALA comes from food such as flaxseed, walnuts, almonds, and soybeans, but it must be converted into EPA, which (like DHA) comes from oily fish -- think salmon, sardines, herring, and mackerel -- so Politi says fish are the best source.

Elisabetta Politi, RDOmega-3s are proven to be energy sources for muscles and a boost to heart health. “They help lower the risk of heart rhythm problems, lower triglycerides, raise HDL (“good”) cholesterol, decrease blood pressure, and maintain healthy blood vessels,” says Politi. There are also claims that omega-3s can improve your metabolism, mood, and thinking -- Politi says that researchers are investigating its positive effects on cognitive function, but she’s yet to see research that supports using it for weight management or emotional well-being.

Chew, Then Swallow

According to the American Heart Association, omega-3 fatty acids are best sourced through food, but to do so would mean eating a 3-ounce serving of salmon or 1 tablespoon of ground flaxseed every day. Add to that concerns over toxins found in some fish species, and fish-oil pills -- stripped of contaminants during the manufacturing process -- become an appealing way to fill the gap.

“As with any dietary supplement, if you decide to take fish-oil pills, tell your doctor so you can avoid any potential drug interactions,” says Politi.

The Omega Seesaw

Not all omegas are created equal, it seems. Omega-6 fatty acids, which ideally work with omega-3s in the body to keep us healthy -- can cause havoc when in excess. “In the last 30 to 40 years, we have dramatically increased the levels of omega-6 fatty acids in our diets,” says Politi. “Omega-6 fatty acids come from cheap-quality oils, and the food industry puts it in anything processed -- rice casseroles, chicken nuggets, frozen dinners, you name it.”

When omega-6 dominates omega-3, the body responds with increased inflammation, which is associated with a higher risk of heart disease, osteoporosis, and cancer. The solution? Stick with fresh, unprocessed foods as much as you can.

Pardon Me

Fish-oil pills can have their own problems: primarily, the “fish burp.” To reduce a fishy aftertaste -- and remain in good standing with your friends and family -- take the pill prior to a meal, freeze it, or look for coated versions.