From the Guidelines
The optimal levels of fatty acids in the diet should include a balance of omega-3 and omega-6 fatty acids, with a focus on consuming at least 1 to 2 fish servings (3.5 oz per serving), preferably oily fish, per week, as recommended by the American Heart Association 1. To achieve this balance, adults should aim for a total fat intake comprising 20-35% of daily calories, with saturated fats limited to less than 10% of daily calories, and trans fats avoided entirely.
- The long-chain n-3 PUFAs, eicosapentaenoic acid (20:5n3) and docosahexaenoic acid (22:6n3), are the most closely associated with lower CVD risk, and can be found in high levels in cold-water oily fish such as salmon, anchovies, herring, mackerel, and sardines 1.
- Consuming one fatty fish serving per week (4 oz) such as salmon provides the recommended daily intake of LC n-3 PUFAs (≈250 mg/d), whereas multiple servings of lean fish such as cod are required to achieve the recommended intake 1.
- Individual needs may vary based on health conditions, with higher omega-3 intake potentially beneficial for those with inflammatory or cardiovascular conditions, and consulting with a healthcare provider before starting supplements is advisable, especially for those on blood-thinning medications, as omega-3s can have anticoagulant effects. The European Society of Cardiology and the European Atherosclerosis Society also recommend a total fat intake of 25-35% of calories for adults, with a focus on sources of MUFAs and both n-6 and n-3 PUFAs, and limiting saturated fat intake to less than 10% of the total caloric intake 1.
From the Research
Optimal Levels of Fatty Acids
- The optimal ratio of omega-6 to omega-3 fatty acids may vary with the disease under consideration, as chronic diseases are multigenic and multifactorial 2, 3.
- A lower ratio of omega-6/omega-3 fatty acids is more desirable in reducing the risk of many chronic diseases, such as cardiovascular disease, cancer, and inflammatory and autoimmune diseases 2, 3.
- Studies have shown that a ratio of 4/1 was associated with a 70% decrease in total mortality in the secondary prevention of cardiovascular disease, while a ratio of 2.5/1 reduced rectal cell proliferation in patients with colorectal cancer 2, 3.
- Increasing intake of omega-6 PUFA linoleic acid has been associated with lower risk of cardiovascular diseases, and increasing intake of arachidonic acid (up to 1500 mg/day) has no adverse effect on platelet aggregation and blood clotting, immune function and markers of inflammation 4.
- Higher intakes of omega-3 PUFAs, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are associated with a lower incidence of chronic diseases characterized by elevated inflammation, including cardiovascular diseases 4, 5.
- Omega-3 fatty acids have antioxidant and anti-inflammatory roles, and are considered to regulate platelet homeostasis and lower risk of thrombosis, indicating their potential use in COVID-19 therapy 4.
- A proportionally higher consumption of n-3 PUFAs can protect against inflammatory diseases, cancer, cardiovascular diseases, and other chronic diseases, as EPA and DHA give rise to anti-inflammatory eicosanoids 5.