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Recent study devises “omega-3 calculator” to help researcher determine proper EPA and DHA doses

Sebastian Krawiec


Researchers' model equation might make it possible to determine how much omega-3 EPA and DHA is needed to elevate the omega-3 index to the desired level.


This study shows that very different doses of supplementation are likely to be needed to achieve optimal blood levels of the long-chain omega-3 fats, EPA and DHA, depending on an individual's baseline status.

These findings may help to explain some of the inconsistent findings from clinical trials of omega-3.  Most such trials use a fixed dose, and in many cases this may be insufficient to raise blood levels enough for participants to experience any benefit. 

Adequate supplies of EPA and DHA are essential for both cardiovascular and brain health, and research evidence indicates that an 'omega-3 index' of 8% or more is the ideal - meaning that together, EPA and DHA make up 8% of total blood fats.  By contrast, an omega-3 index of less than 4% is reliably linked with higher risks for cardiovacular disease, and with a wide range of other physical and mental health disorders.

Here, the researchers used data from human clinical trials to calculate the effects of supplementation, taking into account baseline EPA/DHA status, and used the results to create a formula that can better inform the design of future clinical trials.

Their formula shows that to achieve optimal blood and tissue levels of EPA and DHA within 3 months from supplementation, doses ranging from 750mg/day to 2500mg/day may be required, depending on whether the initial omega-3 index is as high as 6%, or as low as 2%.

The form of omega-3 supplement also makes a difference - as slightly less omega-3 EPA+DHA is required to reach a target level if these fatty acids are provided in their natural, triglyceride form, rather than as ethyl esters (the form often used in more concentrated supplements).

Read the research abstract here:

28 August 2019 - Nutritional Outlook

A recent study published in the American Journal of Clinical Nutrition attempted to model the effects of omega-3 EPA and DHA supplementation on the omega-3 index of subjects.

The model equation the researchers devised might make it possible to determine how much omega-3 EPA and DHA is needed to elevate the omega-3 index to the desired level.

This is significant because there have been wide differences in study results, likely due to a wide variation of dosages, with lower doses having little to no effect on EPA and DHA in the blood, while higher doses have significantly better results. This has left many to question the efficacy of omega-3 supplementation.

Using the method outlined in the study might help researchers achieve the results they are looking for. “Hopefully, ensuring the dose of EPA and DHA is high enough to reach a target omega-3 index level will clarify whether or not EPA and DHA are effective,” said Kristina Harris Jackson, PhD, RD, co-lead author of the study, in a press release.

The format also influences the dosage. For example, in ethyl ester form, reaching 8% omega-3 index in 13 weeks with a baseline omega-3 index of 4% would require 2500 mg per day, while a triglyceride form would require about 1750 mg per day.