DHA: the crucial omega-3

Of the two omega-3 fatty acids that are best explored, EPA and DHA, it is likely DHA that exerts the most blood pressure- and heart rate-reducing effects. Here are the data of Mori et al in which 4000 mg of olive oil, purified EPA only, or purified DHA only were administered over 6 weeks:

□ indicates baseline SBP; ▪, postintervention SBP; ○, baseline DBP; •, postintervention DBP; ⋄, baseline HR; and ♦, postintervention HR.

In this group of 56 overweight men with normal starting blood pressures, only DHA reduced systolic BP by 5.8 mmHg, diastolic by 3.3 mmHg.

While each omega-3 fatty acid has important effects, it may be DHA that has an outsized benefit. So how can you get more DHA? Well, this observation from Schuchardt et al is important:

DHA in the triglyceride and phospholipid forms are 3-fold better absorbed, as compared to the ethyl ester form (compared by area-under-the-curve). In other words, fish oil that has been reconstituted to the naturally-occurring triglyceride form (i.e., the form found in fresh fish) provides 3-fold greater blood levels of DHA than the more common ethyl ester form found in most capsules. (The phospholipid form of DHA found in krill is also well-absorbed, but occurs in such small quantities that it is not a practical means of obtaining omega-3 fatty acids, putting aside the astaxanthin issue.)

So if the superior health effects of DHA are desired in a form that is absorbed, the ideal way to do this is either to eat fish or to supplement fish oil in the triglyceride, not ethyl ester, form. The most common and popular forms of fish oil sold are ethyl esters, including Sam's Club Triple-Strength, Costco, Nature Made, Nature's Bounty, as well as prescription Lovaza. (That's right: prescription fish oil, from this and several other perspectives, is an inferior product.)

What sources of triglyceride fish oil with greater DHA content/absorption are available to us? My favorites are, in this order:

Ascenta NutraSea
CEO and founder, Marc St. Onge, is a friend. Having visited his production facility in Nova Scotia, I was impressed with the meticulous methods of preparation. At every step of the way, every effort was made to limit any potential oxidation, including packaging in a vacuum environment. The Ascenta line of triglyceride fish oils are also richer in DHA content. Their NutraSea High DHA liquid, for instance, contains 500 mg EPA and 1000 mg DHA per teaspoon, a 1:2 EPA:DHA ratio, rather than the more typical 3:2 EPA:DHA ratio of ethyl ester forms.

Pharmax (now Seroyal) also has a fine product with a 1.4:1 EPA:DHA ratio.

Nordic Naturals has a fine liquid triglyceride product, though it is 2:1 EPA:DHA.

Comments (5) -

  • Jakub Polec

    5/22/2013 5:59:53 PM |

    In some DHA, or DHA+EPA supplements one can find additions with for lipase-enhanced digestion which support absorption of n-3 FA. Therefore any supplements with > 1g/d DHA+EPA (or purely DHA) should influence our health.

  • Susie

    5/30/2013 1:02:21 PM |

    Dr. Davis,

    Very happy to learn this distinction between forms of the fats. Are triglyceride and phospholipid two different forms or are they the same? Do you happen to know anything about the Swanson brand which has an EcoMarine trademark?

    Thank you,


  • john pop

    6/11/2013 12:33:21 AM |

    Dr Davis, what about Nordic Naturals DHA Xtra Strawberry softgels?

  • Annette

    6/11/2013 2:35:31 AM |

    I've been totally grain-free and dairy-free for over a yr.  My total chol is 177, HDL is 83, LDL is 88, Triglycerides are 30 and risk factor 2.7, but a 64-slice heart scan done in May 08 showed plaque to two coronary arteries.  I had a stroke in my 40's and lost the sight of one eye.  My dad died of a stroke at age 35.  My grandfather died at 68 of a heart attack.  I'm 70+.  On my insulin sensitivity score ranging from 0-100, I scored 1.  Dr Douglas Brown, Brookfield said, "I've never seen such a low score for insulin sensitivity or triglycerides.  My BP fluctuates wildly.  Some days I don't require any Lisinopril and other days I require 20+ mg.  He thinks I should have a heart cath, but with such great labs, I highly doubt that Medicare would approve.  I wish I knew what to do about the BP.  I do go to Pulmonary Rehab classes for bronchiectasis, but I'm chronically fatigued.  We've had both radon and mold remediation done at our home and a Naturopathic dr told me I have an extreme amt of lead toxicity.  I need advice.

    I have your book and your CD's.  Listening to the CD's is what made my husband decide to go off grains, other than a little rice occasionally.  He dropped 20lbs fairly quickly.

  • DDR

    6/23/2013 12:59:33 PM |

    I get very itchy skin when taking more that 2 capsules of Nordic naturals. Any reason for this? Advice?

You're at the cutting edge

You're at the cutting edge

If you're a participant in the Track Your Plaque program for atherosclerotic plaque regression, you are at the cutting edge of health.

Few physicians give this issue any thought. Chances are, for instance, that if you were to bring up the subject of reversal of heart disease to your primary care physician, you'd get a dismissive "it's not possible," or " Yeah, it's possible but it's rare."

Ask a cardiologist and you might make a little more progress. He/she might tell you that Lipitor 80 mg per day or Crestor 40 mg per day might achieve a halt in plaque growth or a modest reduction of up to 5-6%. If they've tried this strategy, they would likely also tell you that hardly anybody can tolerate these doses for long due to muscle aches. I'd estimate that 1 of 10 of my colleagues would even be aware of these studies.

Both groups are, however, reasonably adept at diagnosing chest pain, an everyday occurrence in hospitals and offices. Chest pain, for them, is a whole lot more interesting. It holds the promise of acute catastrophe and all its excitement. It also holds the key to lots of hospital revenues. Did you know that 80% of all internal medicine physicians are now employees of hospitals? They're also commonly paid on an incentive basis. More revenues, more money.

Ask Drs. Dean Ornish or Caldwell Esselstyn about reversal of heart disease and they will tell you that a very low-fat diet (<10% of calories)can do it. That's true if you use a flawed test of coronary disease like heart catheterization (angiograms) or nuclear stress tests (Ornish calls them "SPECT"). It would be like judging the health of the plumbing in your house by the volume of water flowing out the spigot. It flows even when the pipes are loaded with rust.

In the Track Your Plaque experience, extreme low-fat diets (i.e., high wheat, corn, and rice diets) grotesquely exagerrate the small LDL particle size pattern, among the most potent triggers for coronary plaque growth. This approach also makes your abdomen get fatter and fatter and inches you closer to diabetes. Triglycerides go up, inflammation increases.

If you were able to measure the rust in the pipes, that would be a superior test. You can measure the "rust" in your "pipes," the atherosclerotic plaque in your coronary arteries, using two methods: CT heart scans or intracoronary ultrasound. Take your pick. I'd choose a heart scan. It's safe, accurate, inexpensive. I've performed many intracoronary ultrasounds for people in the midst of heart attacks or some other reason to go to the catheterization laboratory. But for well people, without symptoms, who are interested in identifying and tracking plaque? That's the place for heart scans.

In our program, 18-30% reductions in heart scan scores are common.

Comments (3) -

  • farseas

    12/6/2011 5:01:54 PM |

    Dr. Eselstyn claims that animal protein damages the endothelium.  Dr. Weil says that a high fat meal lowers artery function.   But I had a heart attack and have a stent and have been following your diet for about a year.  If I start eating significant quantities of carbs, I used to get chest pains.  Since then I have went from 305 to 235 and want to get to 175.  I got the stent three years ago.

    Is there any truth to either Weil's or Esselstyn's claims?

    Now I take no medication except a daily 325mg aspirin and a bunch of supplements, including hawthorne and of course, fish oil.  I control my blood pressure with medical MJ and it works great to lower my blood pressure.

    Do I need to worry about saturated fat and high blood pressure?  I used to be on Plavix, blood pressure medication, and statins.  I tried three different statins and they all caused me leg pains.  In fact I seem to have chronic but intermittent leg pain since the statins.

  • Dr. William Davis

    12/6/2011 5:28:45 PM |

    I don't think so.

    They understand this disease incompletely. I can't blame an ENT surgeon for not fully understanding a disease he has never treated.

  • bob stanton

    12/13/2011 3:39:07 PM |

    Esselstyn says this based on the fact that animal protein has higher levels of methionine.  But this study,  Toxicity of Methionine in Humans, by Peter J. Garlick, refutes this claim:
    Conclusions. Although methionine was labeled as being the most toxic amino acid in relation to growth in animals (1), the evidence in humans does not point to serious toxicity, except at very high levels of intake. Despite the function of methionine as a precursor of homocysteine, and the role of homocysteine in vascular damage and cardiovascular disease, there is no evidence that dietary intake of methionine within reasonable limits will cause cardiovascular damage. A single dose of 100 mg/kg body weight has been shown to be safe, but this dose is about 7 times the daily requirement for sulfur amino acids, and repeated consumption for 1 wk was shown to result in increased homocysteine levels (37,42). Daily doses of 250 mg (i.e., 4 mg/kg per day) are only 25% of the daily requirement and have been shown to be safe. Overall, the literature suggests that the single dose which is typically given in the methionine loading test (100mg/kg/d) does not cause any serious complications, except in the extreme case when a 10-fold excess of methionine appears to have been given, and in patients who have schizophrenia or inborn errors of sulfur amino acid metabolism, such as hypermethioninemia.