Lower Inflammation with Fish, Fish Oil, and EPA/DHA
Special attention should be paid to the preformed, long-chain omega-3 fats EPA and DHA. These fats are found in plentiful amounts in oily fish and play double duty for our health. Not only will they have beneficial effects on cholesterol levels, but they will also potentially lower levels of inflammation. Medical researchers are unsure about how large a role inflammation plays in the development of CVD, but we do know that it plays at least some role, and likely an important one.
Even more importantly, individuals with the highest levels of EPA and DHA have the lowest rates of death amongst those with CVD, suggesting that these omega-3s play an important protective role. While we can form our own EPA and DHA from the plant-based omega-3 ALA, research suggests that ALA has only a fraction of the power of EPA/DHA. The most likely reason for this is that our body only poorly converts ALA to EPA (about 10 to 15%), so we only wind up with a fraction of the bioactive final products EPA and DHA. ALA, and the foods which contain it (chia and flax seeds, for example) are still extremely healthy and will play a role in reducing CVD risk, they just won’t reduce it in the same manner as fish or fish oil would.
Since it can be tricky to get optimal levels from diet alone due to the high mercury content of many fish and also because of cost, supplementing with fish oil is useful. Optimally, you should get between 2 and 4 grams per day, but studies have also been done on amounts as high as 6 grams per day. There isn’t evidence that amounts greater than 6 grams are any more effective than 2 to 4 grams, so there is no need to add more than 6 grams per day to your diet (including food sources, like sardines).
Should You Avoid Omega-6 Fats?
This is a hot question in the research world right now because the evidence is somewhat conflicting. On the one hand, we have evidence that a high intake (or more importantly, a disproportionate intake) of omega-6s can cause an overall increase in inflammation. If inflammation is a potential risk factor for CVD, then it would make sense to avoid omega-6s as much as possible. On the other hand, omega-6s still have a significant, positive benefit on cholesterol levels, which are an overall greater risk factor than inflammation.
In the end, the question is somewhat more important in our understanding of CVD risk than it is clinically meaningful. The majority of omega-6s in the typical diet of an American come from processed foods, which should be avoided for many more reasons than high omega-6 content alone. If you remove junky foods from your diet (which you should if you are at high risk for CVD), then the sources of omega-6s you have left are primarily nuts, seeds, and animal products, none of which contain nearly as large an amount of omega-6s as the typical junk food.
Omega-6s are still an essential fat—our body needs them and cannot produce them itself. There’s no need to avoid nuts, seeds, or meats high in omega-6s (and low in saturated fat), but you should remove foods which are overtly high in omega-6s and otherwise low in health-promoting nutrients.
As a quick guide, the vast majority of oils used in the production of processed foods are high omega-6 oils. Peanut oil, safflower oil, cottonseed oil, and soybean oil are all primarily composed of omega-6s. Sunflower seed oil requires some closer label reading, as it exists in two forms. If you have a choice, get the type called “high-oleic sunflower oil”—oleic acid is the same monounsaturated fat that gives olive oil its heart-healthy claim to fame. If the label doesn’t explicitly say which is used, you can look at the fat breakdown if it’s there. Omega-6s are polyunsaturated fats, oleic acid (an omega-9) is a monounsaturated fat, so you can tell which type was used by which fat is found in larger amounts. Omega-3s are also polyunsaturated, but you’ll be hard-pressed to find them in processed food!