Editor: this article was written in 2013. Our understanding of DHA’s role in health has changed in that time. Optimal brain health requires more DHA than this piece suggests. More here.
Here’s another reason why OmegaVia is high in EPA and low in DHA:
DHA Omega-3 – a little bit goes a long way.
Everyone knows babies need DHA for brain development. Even as adults, there is more DHA in your brain than anywhere else.
So we should be taking lots of DHA every day, right?
Your brain absorbs only about 4 mg of DHA per day.
That’s right. Four milligrams. Per day.
3.8 mg to be exact.
C’mon, stop it! That’s the machine they used in Back to the Future!
Would you feel any better if I told you that they used an ‘adaptive fuzzy C-means algorithm’ to compute all this?
Actually, it makes sense when you read the second revelation from the paper:
DHA is very, very long-lasting
DHA has a half-life of 2.5 years or 911 days.
What does that mean, Doc?
It’s the time to use up half of what you started with.
It means that if your brain absorbed 2 drops of DHA today, one of those two drops will have been used up after 911 days. And the other drop would still be in your brain.
Now the 4 mg per day number starts to makes sense.
If your brain can absorb just 4 mg per day and 2 of that 4 mg will still be around after 911 days, then DHA really is long-lasting.
This is a key difference between EPA and DHA: DHA is a structural Omega-3 while EPA is a functional Omega-3.
If you think of your body as a building, the DHA is part of the structure – like paint or tile. It’s there for a while. EPA on the other hand, is like the water or electricity flowing through the building. Here now and beta-oxidized (gone) tomorrow.
This changes many news headlines…
Now that you know the DHA can’t be put into or taken our of your brain for several years…
The average observation period in clinical trials need to take this finding into consideration. Studies on Omega-3 and brain health may need to be 5 or 10 years long to give useful data. Most studies to date have been much shorter.
What do you think of news headlines likes this? ‘Fish oils don’t help ward off dementia.’
How much DHA does your brain need per year?
3.8 mg per day times 365 day = 1,387 mg DHA per year.
That’s as much as your brain can possibly absorb.
Remember, this does not include DHA that’s needed in your eyes, heart or sperm (if you’re male.) These are the other places where DHA is deposited. And smaller amounts in other cell membranes.
But the lion’s share is in the brain.
This does not mean you don’t need DHA!
On the contrary…every one needs and MUST have DHA. It must be consumed from foods and supplements.
If you took an excess of DHA every day – which most of us taking fish oil supplements do – your body will convert some of the DHA into EPA.
This process is called retroconversion.
Our bodies are capable of converting DHA to EPA using enzymes, but it is not an efficient conversion. Our bodies are not very good at it.
Converting EPA back to DHA is even less efficient. Why? Because it’s a two-step process – it needs an elongase enzyme followed by beta-oxidation.
There are several metabolic factors that influence these elongation and retroconversion steps. Sources: Hansen et al. Lipids. 1998 Feb;33(2):131-8 and Grimsgaard et al. Am J Clin Nutr. 1997 Sep;66(3):649-59. Read full paper here.
Only 10% of DHA is converted to EPA
Dr. Bruce Holub from the University of Guelph estimates that only 9.4% of DHA is retroconverted into EPA. Source: Conquer & Holub. Dietary docosahexaenoic acid as a source of eicosapentaenoic acid in vegetarians and omnivores. Lipids. 1997 Mar;32(3): 341-5.
What does this mean if you follow Dr. Oz’s advice of taking 600 mg DHA per day?
Well, it means you’d meet all your daily DHA needs. That’s good.
But your body will get only 60 mg of EPA from it.
Not enough! Not even close.
However, if you’re a more-is-better type person and decide to turbo-charge Dr. Oz’s 600 mg DHA recommendation to 6000 mg, you may have a problem…
[Geek alert: Eicosanoid pathway alphabet soup coming up!]
DHA competes with GLA for an enzyme called delta-6-desaturase. This means your body makes less GLA. And that reduces the production of DGLA downstream.
DGLA is the source of several beneficial molecules.*
You don’t want to block DGLA production with too much DHA. So that’s the short-term risk of taking too much DHA.
So if you take too much DHA, take a little GLA from Borage oil for a day or two.
Bottom-line: you need a little DHA every day. But certainly not the mega-doses being preached.
In part 3, we’ll discuss why EPA is the Omega-3 with the mood benefits.*
*Individual results may vary. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Clinical research suggests the omega-3 dosage needed to help maintain healthy triglycerides is 2000-3000 mg per day when used as part of healthy diet and exercise.