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#83 – Bill Harris, Ph.D.: Omega-3 fatty acids — Whalespan

Content›Video›#83 – Bill Harris, Ph.D.: Om…

#83 – Bill Harris, Ph.D.: Omega-3 fatty acids

Peter Attia2h 2m · 2020-01-14

Support Rate

58%

121 of 208 claims supported

Support rate

121 of 208 claims supported

121 supported87 partial / not

Claims from this content

157

✓Well SupportedThe Omega-3 Index, measuring omega-3 levels in red blood cells, is a long-term biomarker of omega-3 status, unlike plasma phospholipid levels which reflect recent intake.✓Well SupportedIncreasing the omega-3 index to a higher level (e.g., 8%) is associated with longevity benefits, including improved cardiovascular health and reduced inflammation.✓Well SupportedOmega-3s from krill oil in phospholipid form yield higher plasma EPA and DHA concentrations than triglyceride or ethyl ester forms at identical doses.✓Well SupportedThe omega-3 index is a more accurate long-term marker of omega-3 status than plasma phospholipid levels.✓Well Supported4 grams of EPA per day, taken with a statin, reduces macrovascular outcomes, particularly in individuals with high triglycerides.

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A. Volkovreader

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Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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✓Well SupportedSaturated fat might be a normal adaptive response to maintain cell membrane fluidity, even if it raises LDL cholesterol.

✓Well SupportedFree fatty acid omega-3s are absorbed without enzymatic conversion, unlike triglyceride or ethyl ester forms.

✓Well SupportedThe VITAL study found that 800mg of Lovaza (prescription EPA/DHA) reduced heart attack risk by approximately 30% compared to placebo over five years.

✓Well SupportedThe omega-3 index test should be used to determine appropriate dosing, as individuals may not raise their index even with 2-3 grams of ethyl ester form.

✓Well SupportedSpecialized pro-resolving mediators (SPMs) are crucial for inflammation resolution.

◐Partially SupportedInconsistent findings in omega-3 health benefit studies may be due to reliance on self-reported dietary intake, which is less accurate than measuring blood levels.

◐Partially SupportedSaturated fats have no double bonds, monounsaturated fats have one, and polyunsaturated fats have two or more.

◐Partially SupportedIn humans, the conversion rate of ALA to EPA is 5-8%, and to DHA is 0.5-5%.

✓Well SupportedMajor dietary sources of linoleic acid include vegetable oils and sometimes adulterated avocado and olive oils.

✓Well SupportedTallow and butter contain approximately 2% linoleic acid, whereas corn or soybean oil contain 40-55% linoleic acid.

✓Well SupportedEPA is considered a heart-healthy oil due to mechanisms including reducing platelet stickiness and resolving inflammation.

✓Well SupportedOmega-3 fatty acids increase cell membrane fluidity, which is cardioprotective.

✓Well SupportedDr. Bill Harris has received five NIH grants and published over 300 papers on the effects of EPA and DHA on human health.

✓Well SupportedThe most effective way to improve health related to omega-3 and omega-6 balance is to increase EPA and DHA intake, rather than solely lowering omega-6 intake.

◐Partially SupportedPrescription omega-3 medications like Lovaza and Vascepa are used for hypertriglyceridemia.

◐Partially SupportedHigh doses of DHA can raise LDL cholesterol, particularly in individuals with hypertriglyceridemia, though the clinical significance is unknown.

◐Partially SupportedNormal red blood cell EPA and DHA levels are typically around 5-6%.

◐Partially SupportedIn the REDUCE-IT study, EPA lowered triglycerides by approximately 15% and had virtually no change on LDL-C and ApoB.

◐Partially SupportedRed blood cell omega-3 levels are more stable and preferred markers compared to plasma levels.

◐Partially SupportedThe position of the first double bond from the end of a fatty acid molecule determines its classification as omega-3 or omega-6.

◐Partially SupportedThe FDA-approved dose for Lovaza is 4 grams per day.

✕Not SupportedEven high oleic safflower and sunflower oils are problematic due to concerns about excess oleic acid consumption.

◐Partially SupportedPCSK9 inhibitors have had a significant impact on residual cardiovascular risk in patients who are maximally statin-treated, with average LDL cholesterol around 74 mg/dL.

✓Well SupportedConsuming large amounts of omega-6 or omega-9 polyunsaturated fats can replace saturated fatty acids in cell membranes, potentially affecting membrane fluidity.

✓Well SupportedA low EPA to arachidonic acid ratio of 0.1 is acceptable and within a healthy reference range greater than 0.2.

✓Well SupportedMarine Omega-3 has a strong protective effect against heart disease, particularly in heavy smokers.

✓Well SupportedHigh doses of fish oil (18-20 grams of EPA and DHA) significantly reduce very high triglyceride levels.

✓Well SupportedInternational bodies state up to 5-6 grams daily of EPA and DHA is safe.

✓Well SupportedFish typically contain EPA and DHA in a 60/40 or 40/60 ratio, and obtaining both is recommended.

✓Well SupportedThe omega-3 index (total EPA and DHA) is a preferred biomarker over ratios like AA:EPA or omega-6:omega-3.

✓Well SupportedSalmon is a good food source for EPA and DHA with low mercury exposure.

◐Partially SupportedAlpha-linolenic acid (ALA) can be elongated in the liver to form EPA, a 20-carbon, 5-double-bond omega-3 fatty acid.

◐Partially SupportedIn people with high triglyceride levels, 6 grams/day of EPA and DHA can increase LDL and ApoB.

◐Partially SupportedThe drug Empanova (Epanova) contains 4 grams total of EPA plus DHA as free fatty acids.

✓Well SupportedOmega-3 EPA may play a role in stopping inflammatory events that precipitate cardiovascular events.

◐Partially SupportedOmega-3s (EPA and DHA) make platelets less reactive and less likely to clot, which is protective against heart attacks.

✓Well SupportedThree papers published in the New England Journal on May 9th, 1985, linking omega-3s to significant triglyceride reduction, were pivotal in bringing omega-3s to widespread attention.

◐Partially SupportedDHA is the most common omega-3 fatty acid in cell membranes, with significantly higher levels than EPA.

✓Well SupportedHigher blood levels of linoleic acid are associated with lower risk of cardiovascular disease.

✓Well SupportedPlasma omega-3 levels are more variable day-to-day due to changes in triglyceride and fatty acid intake.

◐Partially SupportedA free fatty acid omega-3 version (Epanova) is expected to be available soon, potentially with similar or greater success than REDUCE-IT.

◐Partially SupportedFish oil supplements provide similar cardiovascular benefits to eating fish.

◐Partially SupportedAverage daily consumption of DHA in the U.S. is approximately 100 milligrams.

◐Partially SupportedEPA and DHA from omega-3 fatty acids should be considered potent drugs, particularly for individuals at risk of cardiovascular disease.

◐Partially SupportedAdvanced processing of omega-3 oils allows for highly concentrated EPA and DHA products, blurring the line between supplements and drugs.

◐Partially SupportedThe DHA component of omega-3s may slow down LDL receptor activity, leading to increased LDL levels.

◐Partially SupportedLinoleic acid intake increased in the 20th century while heart disease death rates decreased.

◐Partially SupportedEPA may provide unique anti-inflammatory effects in brain circulation affecting depressive symptoms.

◐Partially SupportedThe cardiovascular benefit of omega-3 fatty acids may not be primarily due to lowering triglycerides.

◐Partially SupportedOmega fatty acid analysis can be ordered online from OmegaQuant.

◐Partially SupportedFeeding salmon oil to subjects not on a restricted diet increased their body fat by approximately 25 grams, composed of polyunsaturated omega-3.

✕Not SupportedDHA is not definitively the brain omega-3 and EPA is not definitively the heart omega-3, nor is one better than the other for any given system.

✕Not SupportedThe omega-3 to omega-6 ratio is imprecise and difficult to act upon.

✓Well SupportedThe body has a significant buffering capacity for high amounts of linoleic acid.

◐Partially SupportedFish oils predominantly contain Omega-3 fatty acids, while vegetable oils like safflower, corn, and sunflower oil are rich in Omega-6 fatty acids.

◐Partially SupportedA saturated fatty acid molecule is a straight chain of carbons and hydrogens with no double bonds, ending in a carboxylic acid group.

◐Partially SupportedOmega-6 fatty acids produce inflammatory eicosanoids, while Omega-3 fatty acids are considered non-inflammatory or anti-inflammatory.

◐Partially SupportedMonounsaturated fats contain one double bond in the fatty acid chain, which affects the fluidity of membranes and lipoproteins.

✓Well SupportedHigh levels of linoleic acid in the blood are associated with a lower risk of heart disease, myocardial infarction, and diabetes.

◐Partially SupportedThe 1977 recommendation to reduce saturated fat intake likely spurred research into the effects of polyunsaturated fats on cholesterol levels.

✓Well SupportedRed blood cell fatty acid analysis can provide insights into an individual's fat composition and potential reasons for metabolic issues.

◐Partially SupportedThe body is generally more adept at regulating its internal composition than simply reflecting dietary intake, particularly concerning saturated fat in cell membranes.

◐Partially SupportedEach tissue and cell type has a unique pattern of fatty acid composition in its membranes determined by the cell's role in metabolism and its need for specific physical characteristics.

✕Not SupportedThe omega-3 to omega-6 ratio is a red herring and distracts from the core issue of excess omega-6 consumption.

◐Partially SupportedThe nomenclature of fatty acids conveys information about their saturation level, carbon chain length, and the position of the first double bond.

◐Partially SupportedArachidonic acid levels in the blood were unrelated to the risk of heart disease or diabetes.

◐Partially SupportedThe concern regarding arachidonic acid is whether its pro-inflammatory activity becomes excessive and unresolved.

◐Partially SupportedIndividual variability in mercury levels is significant, regardless of tuna consumption frequency.

✕Not SupportedChewing on substances like mastic gum or hard candies can potentially disrupt metal fillings and liberate mercury.

◐Partially SupportedHigher intake of ALA is associated with a reduced risk for disease, potentially through its own metabolites rather than conversion to EPA and DHA.

◐Partially SupportedPeter Attia's red blood cell omega-3 levels are approximately 10-11% EPA and DHA.

◐Partially SupportedAlpha-linolenic acid (ALA) is an essential omega-3 fatty acid found in flaxseed and chia seed oil that the body cannot synthesize.

◐Partially SupportedOmega-3 fatty acids' role in health was discovered by observing the paradox of Eskimos having low rates of heart disease despite a high-fat diet.

◐Partially SupportedArachidonic acid levels are tightly controlled and do not significantly decrease even with a complete dietary restriction of linoleic acid.

◐Partially SupportedArachidonic acid, derived from linoleic acid, is pro-inflammatory and plays a role in the body's natural inflammatory response.

◐Partially SupportedLess than 1% of ingested linoleic acid is converted into arachidonic acid.

◐Partially SupportedThe decrease in heart disease rates with increased linoleic acid intake may be confounded by statin use, ACLS, and reduced smoking.

◐Partially SupportedThe field of omega-3 fatty acid research has been confusing for most of its history.

◐Partially SupportedIt is remarkable that cardiovascular disease events can be reduced within a 2-5 year timeframe, given that the disease process begins at birth.

✕Not SupportedConclusions about fatty acids being 'good' or 'bad' are often based on overly simplistic views of complex biology.

◐Partially SupportedReplacing saturated fat intake with mono- and polyunsaturated fats, rather than sugar, would have prevented current public health problems related to fat consumption.

◐Partially SupportedThe fatty acid composition selected for red blood cell membranes is influenced by the blood's fatty acid availability, but the bone marrow has a degree of control over what is incorporated.

◐Partially SupportedA 1977 US Senate committee concluded Americans should significantly reduce saturated fat intake, despite weak evidence implicating it in heart disease.

◐Partially SupportedBefore the 20th century, diets primarily consisted of saturated and monounsaturated fats, along with EPA and DHA, and people did not live long lives.

◐Partially SupportedThe conversion pathway for omega-3s is ALA to EPA to DHA, with DHA not converting back to EPA.

◐Partially SupportedLow omega-3 status has significant implications and assessing it should be as important as measuring cholesterol.

◐Partially SupportedFasting and time-restricted eating can pose a problem for absorbing ethyl ester or triglyceride omega-3s due to their requirement for enzymatic conversion.

◐Partially SupportedThe study on omega-3 fatty acids had methodological and statistical limitations, potentially masking real benefits in specific subgroups like reduction in myocardial infarction (MI).

◐Partially SupportedThere is no substantial difference in quality between pharmaceutical-grade omega-3 products and those from reputable supplement companies.

◐Partially SupportedTraditional Eskimos consuming a high-fat, high-saturated-fat, high-cholesterol diet were virtually free of acute myocardial infarction.

◐Partially SupportedDr. Bill Harris was an author on two American Heart Association scientific statements concerning fatty acids.

◐Partially SupportedA study on a specific intervention is scheduled to finish next October, with results potentially released on the AHA clinical trials website.

◐Partially SupportedThe liver can convert arachidonic acid into a longer molecule with 22 carbons and up to 5 double bonds.

◐Partially SupportedIncorporating EPA into cell membranes changes their flexibility and fluidity.

◐Partially SupportedIn 1978, Bill Harris's understanding of EPA and DHA was minimal, and he was primarily focused on the effects of salmon oil on cholesterol.

◐Partially SupportedArachidonic acid may not be entirely detrimental.

◐Partially SupportedMeasuring mercury clearance is important for understanding an individual's overall mercury burden.

◐Partially SupportedA study administering 25 grams of EPA and DHA showed reductions in total cholesterol and triglycerides.

◐Partially SupportedCultures that lived off seafood, such as Okinawans historically, likely consumed around 1.5 to 2 grams of EPA and DHA daily.

◐Partially SupportedAdministration of EPA and DHA prolongs bleeding time and drops platelet count.

◐Partially SupportedMeasuring mercury levels is advisable for individuals who consume tuna frequently.

◐Partially SupportedGiving more DHA does not necessarily lead to better brain or eye health, and studies on depression have not shown benefits from high DHA products.

◐Partially SupportedThe Greenland Eskimo studies by Ivar Berg and Bang, published around 1980, investigated omega-3 effects on lipids and platelet function.

◐Partially SupportedThe ratio of arachidonic acid to EPA is more informative than the total omega-6 to omega-3 ratio but omits DHA.

◐Partially SupportedThe VITAL study used a dose of 1 gram of Lovaza and was designed as a primary prevention study for cardiovascular disease and cancer.

◐Partially SupportedWhen taking 2,000 mg of fish oil, if 1600 mg is EPA and DHA (80%), the remaining 400 mg is typically a mixture of monounsaturated and polyunsaturated fatty acids.

◐Partially SupportedThe traditional Eskimo diet was approximately 6-7% of total calories from omega-3 polyunsaturated fats.

◐Partially SupportedPure EPA at four grams may reduce cardiovascular events through mechanisms other than lowering triglycerides or ApoB, potentially involving resolution of inflammation and heart rate variability.

◐Partially SupportedOmega-3 EPA may control heart rate and improve heart rate variability.

◐Partially SupportedThe event risk reduction in the REDUCE-IT study was greater than in PCSK9 inhibitor studies.

◐Partially SupportedConsuming salmon provides about two-thirds of the EPA and DHA found in concentrated salmon oil.

◐Partially SupportedAn EPA-only drug was approved in Japan in the late 1980s and used successfully in the 2007 JELIS trial.

◐Partially SupportedOmega-3 supplementation (specifically salmon oil) can cause a marked drop in platelet count and prolonged bleeding time in some individuals.

◐Partially SupportedPure EPA dietary supplements are not readily available; Carlson's EPA Gems is approximately 75-80% EPA to DHA.

◐Partially SupportedDHA is highly concentrated in the brain and retina, but EPA is virtually absent in the brain.

◐Partially SupportedThe benefit of eating fish may be due to omega-3 fatty acids or other unmeasured components.

✕Not SupportedHigh DHA omega-3 products have not been shown to be effective in treating depressive symptoms.

◐Partially SupportedEPA and DHA are the primary omega-3 fatty acids.

◐Partially SupportedA saturated fatty acid with 16 carbons is called palmitic acid and is designated as 16:0.

✕Not SupportedVascepa (icosapent ethyl) is not recommended for individuals with triglyceride levels of 86 mg/dL, as benefits were observed in patients with significantly higher triglycerides.

◐Partially SupportedEnzymes exhibit specificity for different fatty acids, leading to significant differences in outcomes relative to the starting structure.

◐Partially SupportedArachidonic acid is a 20-carbon, 4-double-bond omega-6 fatty acid that is a substrate for the production of most prostaglandins.

◐Partially SupportedSoybean oil contains about 7% alpha-linolenic acid (ALA).

◐Partially SupportedFor monounsaturated and polyunsaturated fatty acids, the position of the first double bond must be specified.

◐Partially SupportedThe body can dampen diverse dietary inputs to produce modestly banded outputs, but significant differences in health outcomes still exist.

◐Partially SupportedUnderstanding fatty acid pathways requires studying chemical structures and the roles of enzymes like desaturases and elongases.

◐Partially SupportedOleic acid is a monounsaturated fatty acid with 18 carbons and one double bond, designated as 18:1.

◐Partially SupportedSalmon oil lowers triglyceride levels.

◐Partially SupportedLinoleic acid is an essential omega-6 fatty acid that the body cannot synthesize and is crucial for metabolism.

◐Partially SupportedEskimos studied in the 1970s consumed an estimated 6 to 7 grams of EPA and DHA daily.

◐Partially SupportedThe difference in properties between coconut oil and olive oil is attributed to a single double bond.

◐Partially SupportedFatty acids are fundamental components of cell membranes and impact human health.

◐Partially SupportedFats are classified into saturated, monounsaturated, and polyunsaturated chemical families.

◐Partially SupportedOmega-6 fatty acids are not as harmful as commonly believed.

◐Partially SupportedBill Harris's first metabolic ward study investigated the effect of salmon oil on cholesterol levels.

◐Partially SupportedThe average American has an omega-3 index of around 4-5%, which is about half the ideal range.

◐Partially SupportedSaturated fats like lard and butter are solid at room temperature.

◐Partially SupportedDHA metabolites, called protectants, are active in anti-inflammatory processes, improve platelet function, and may lower triglycerides and raise HDL.

◐Partially SupportedEating three oily fish meals per week and taking a supplement increased the chance of achieving an 8% omega-3 index in a study of 3500 people.

◐Partially SupportedPure EPA (vascepa) has demonstrated effectiveness in reducing residual cardiovascular risk in patients on statins, with virtually no side effects and no significant drug interactions.

◐Partially SupportedConsumer Reports testing generally concludes that dietary supplements accurately state their EPA and DHA content and are free of toxins.

◐Partially SupportedFish oil labels should be read carefully as capsules are often large and do not solely contain EPA and DHA.

◐Partially SupportedTriglycerides over 500 mg/dL are classified as very high, and Lovaza is approved at 4 grams per day for this condition.

◐Partially SupportedAlbacore tuna has twice the EPA and DHA of chunk light tuna and more mercury, but its benefits likely outweigh the risks for most people.

◐Partially SupportedSardines, herring, and mackerel are oily fish that generally have high EPA levels.

◐Partially SupportedEPA and DHA levels in cells respond more strongly to dietary intake compared to linoleic acid.

◐Partially SupportedOmega-3 supplements like Lovaza are extremely safe, cheap, and do not interact with other medications.

◐Partially SupportedFish oil lowered cholesterol because it is a liquid fat, not because it is an animal fat.

◐Partially SupportedOmega-3 fatty acids from salmon oil were found to lower cholesterol levels, comparable to vegetable oil.

◐Partially SupportedReducing omega-6 levels in oils may lead to an increased risk for major diseases.

◐Partially SupportedOmega-3, omega-6, and omega-9 fatty acids are referred to by chemists as N-3, N-6, and N-9 fatty acids, indicating the position of the first double bond from the end of the molecule.

◐Partially SupportedThe primary omega-6 pathway discussed is from linoleic acid (LA) to arachidonic acid (AAA).