A new study published in the American Journal of Clinical Nutrition allows researchers to calculate how much omega-3 EPA and DHA to use in their studies in order for subjects to achieve a healthy omega-3 index.
So far, there has been very little evidence as to what dose of EPA and DHA should be tested in a study. And given the wide variation in study results over the past few years, it is likely that dose played a role in the relative success or failure of omega-3 studies. In other words, if the dose of EPA and DHA in a study is not high enough to have an impact on blood levels (i.e. the omega-3 index), it may not have an impact on the desired endpoint, leading to a leads to a neutral result.
Particularly in the case of cardiovascular diseases (CVD), the literature showing the benefits of the omega-3 fatty acids EPA and DHA is mixed. On the one hand, a meta-analysis from 2018 came to the conclusion that current findings do not support any role for omega-3 fatty acids in reducing the risk of CVD.
On the other hand, three large randomized studies reported in late 2018 showed that omega-3 fatty acids significantly reduced the risk of vascular death, myocardial infarction, and serious adverse cardiovascular events. The latter study was particularly convincing because statin-treated patients used 4 g of EPA (as opposed to the usual 0.84 g of EPA and DHA) and found a 25% reduction in risk of CVD events.
Kristina Harris Jackson, PhD, RD, the co-lead author of this latest paper, said, “A low dose could result in a study showing no effects of EPA and DHA, making the literature more indecisive and the medical community more skeptical of omega 3 benefits, “she said. Hopefully, making sure that the dose of EPA and DHA is high enough to achieve an omega-3 index index will clarify whether or not EPA and DHA are effective.
Using the calculator
The model equation developed in this article can be used to estimate the final omega-3 index (and 95% CI) of a population considering the omega-3 EPA and DHA dose and the base omega-3 index. For example, a population with an omega-3 base index of 4.9% who is given 840 mg EPA and DHA per day (as a 1-gram ethyl ester capsule) would have a mean omega-3 index of 6.5% (95%) obtained CI: 6.3%, 6.7%).
By rearranging the equation, one can calculate the approximate doses of EPA / DHA (of forms of triglycerides) required to achieve a mean omega-3 index of 8% in 13 weeks. This would require about 2200 mg of EPA and DHA for a base omega-3 index of 2%, about 1500 mg for a base omega-3 index of 4%, and about 750 mg of EPA and DHA for a base omega-3 index of 6% .
Using this example, Jackson and her colleagues predicted that the minimum dose of EPA and DHA would have to be 95% to be certain that the mean base omega-3 index went from 4% to 8% (in 13 weeks) 1750 mg per day increases a triglyceride formulation or 2500 mg of an ethyl ester formulation per day. Both forms are common in fish oil preparations.
For 95% of the subjects (not just 50%) to achieve a desirable omega-3 index from a baseline of 4%, around 2000 mg EPA and DHA per day (depending on the chemical form) would probably be required.
Do researchers still need the omega-3 index if they have a calculator?
The calculator presented in this document does not eliminate the need for omega-3 index tests. In fact, creating a base omega-3 index is essential to using the calculator.
“The recommended doses are just average responses, but individual responses to EPA and DHA are still very difficult to predict,” said Dr. Jackson. “In a recent consumer cohort, we found that individuals covered the full range of the omega-3 index despite reporting the same amount of fish intake and supplements.”
This paper showed that people who, in a relatively short period of time, e.g. B. want to achieve 8% for three to four months, depending on the omega-3 starting index, require 1 to 2 grams of EPA and DHA per day.
“As mentioned earlier, the equation developed [in this paper] may be helpful in predicting changes in the omega-3 index in the population, but due to the large inter-individual variability in the response of the omega-3 index to EPA and DHA supplementation, it is in the clinical setting where the omega 3 index is tested directly, the preferred approach to assessing EPA and DHA status would probably be less useful, “explained the study’s authors.
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