Omega 3 EPA and DHA, an invincible duo of defenders of the cardiovascular system

Omega 3 EPA and DHA, an unbeatable duo defending the cardiovascular system

The Omega-3 EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) act together and specifically to protect the cardiovascular system. For this reason, ensuring the right intake of both nutrients is the best strategy to achieve the highest possible protective effect for cardiovascular health. This is the advice of Dariush Mozaffarian and Jason Wu, experts from the Harvard School of Public Health in Boston (USA), who published an analysis of the benefits of these two fatty acids based on a series of trials conducted both on humans and animals in the Journal of Nutrition.

The importance of obtaining EPA and DHA through diet

Many studies since the 1970s have demonstrated the cardiovascular benefits associated with Omega-3 found in fish and fish oil. However, no study has clarified whether the two main dietary Omega-3s, EPA and DHA, have overlapping or complementary effects. What is known is that DHA must be consumed directly through diet because the human body can synthesize only small amounts of it from EPA. For EPA, the most effective source is fatty fish, such as salmon, mackerel, and herring, which contain high and readily usable concentrations of EPA. However, part of the EPA required by the human body for maintaining health can be obtained from certain plant-based precursors, such as alpha-linolenic acid (ALA).

Combined intake to maximize benefits

The analysis by Mozaffarian and Wu shows that in some cases EPA and DHA produce the same cardiovascular benefits. Examples include lowering triglyceride levels, arterial health, reduced risk of blood clots, and improvements in some markers of inflammation and oxidative stress. However, other benefits are specifically linked to one of the two Omega-3s. DHA, for example, reduces the risk of fatal heart attacks related to cardiac arrhythmias, while it is unclear if EPA provides this type of protection. Furthermore, DHA has specific actions on cholesterol particles. Conversely, some studies indicate that only EPA reduces the likelihood of non-fatal cardiovascular problems. Based on this evidence, the authors recommend ensuring adequate intake of both EPA and DHA. According to the researchers, this approach allows benefiting from the actions of both Omega-3s throughout life.

An example?

Children cannot synthesize sufficiently high levels of DHA from EPA and therefore must obtain it directly from their diet to take advantage of DHA’s specific actions.

Do plant foods provide enough EPA?

Regarding EPA, researchers noted that the amounts synthesizable from ALA found in plant-based foods, like walnuts, are quite low. However, this source can be important for those who do not consume enough fish and thus might not get the specific benefits of EPA otherwise. Moreover, among possible Omega-3 sources, Mozaffarian and Wu also mentioned purified EPA and DHA supplements, useful to ensure a proper intake of both fatty acids.

Recommended doses

Commenting on their analysis, the researchers emphasized the importance of further studies to better clarify the specific actions of EPA and DHA. Since the full picture of their specific effects is not yet complete, it is currently not possible to state the exact amounts of each fatty acid to take daily. However, to achieve the maximum cardiovascular benefits, total daily intake of EPA+DHA should not fall below 250-500 milligrams.  

Editorial note In Italy and the EU area, recent official guidelines specify precise daily amounts as follows:

• Heart health:250 mg of EPA and DHA contribute to normal heart function.
• Brain and visual functions:250 mg of DHA contribute to the maintenance of normal brain and visual functions.
• Triglyceride levels: 2000 mg of EPA and DHA contribute to maintaining normal triglyceride concentrations in the blood.
• Blood pressure: 3000 mg of EPA and DHA contribute to maintaining normal blood pressure.

Source:

Mozaffarian D, Wu JH, “(n-3) fatty acids and cardiovascular health: are effects of EPA and DHA shared or complementary?”, J Nutr. 2012 Mar;142(3):614S-625S