We talk often about the health and beauty benefits of omega-3 fatty acids. They’re great for your skin because they boost moisture levels and keep down inflammation that can lead to redness, breakouts and aging. That same anti-inflammatory power is also important for your long-term health, decreasing your risk of eye problems like macular degeneration, gum disease and brain rot. The types of omega-3s that you get from fish like salmon and ocean trout (the only two fish in North American with predictable omega-3s), plankton and algae help maintain brain health and cognitive function.

And then there’s omega-6 fatty acid, which you hear about slightly less often and which present a slightly (OK, more than slightly) more complicated picture. Omega-6s are, like omega-3s, polyunsaturated fatty acids (PUFAs) and are found in many of the same sources. At the proper intakes, omega-6s play a really important role in supporting your immune system, providing material needed to produce hormones. But here’s the rub: Too much omega-6 is bad for you. That’s right, some is necessary, but too much is a hazard. Confusing, isn’t it?

A Question of Balance

It may all come down to ratios. The data aren’t good enough to be 100 percent sure, but they’re very persuasive. Both omega-3 and omega-6 fatty acids are considered “essential nutrients,” which means that our bodies require them, but cannot produce them and need to get them through food. Ideally, we should get about the same amount of omega-6s and omega-3s in our diets; a ratio of about 1-to-1 is what our ancestors ate, and thus is postulated to be best (and something in the neighborhood of 4:1 is still pretty good). The problem is that your average American doesn’t get equal amounts of each fatty acid. Not even close. In fact, most estimates say, and the National Nutrition surveys find, that typical Americans who eat a typical Western diet get 15 to 25 times more omega-6s than omega-3s. That may be bad news.

Omega-9 fatty acids are considered “non-essential nutrients,” meaning that the body can produce them on its own, so we don’t need to get them from foods or supplements. Omega-9s are found in olive oil.

Now, we’re not going to pretend that it’s easy to know exactly what ratio of fatty acids you’re getting in your diet, and the only way to know for sure what you’ve got in your system is to do a certain blood test. But the best way to manage your intake is to focus on eating as many omega-3-rich foods as you can, while limiting the foods that skew too far toward omega-6s.

Use this guide to make wise decisions and keep your omegas from getting mega out of whack.

Foods With a Healthy Balance of Omega-3s and Omega-6

  • Walnuts
  • Chia
  • Wild salmon
  • Herring
  • Sardines
  • Ocean trout
  • Fish oil
  • Krill oil (but this contains only a fraction of what is in normal fish oil, and often with too much saturated palmitic acid, i.e. saturated fat)
  • Canola oil
  • Flax seeds and flaxseed oil

Foods With Too Many Omega-6s and Not Enough Omega-3s

  • Corn oil
  • Safflower oil
  • Most non-trans fat margarines
  • Packaged snack foods
  • Most fried and fast foods

MORE: Are You Eating for Beauty?