On: Omega-3 fatty acids

Episode: 83

Date: December 2019

Key Subjects:

• Phd in human nutrition, expert on omega-3 fatty acids, CEO of OmegaQuant
• Basics of fatty acid biochemistry (see also “Fatty Acids”).
• Key markers of omega-3 and -6 typically within fairly narrow range.
  • About 20-30% difference in markers; most people fall within the range.
  • Varies somewhat with dietary intake of fatty acids, but no 2 or 3 fold swings.
  • [Not my experience: EPA tripled in 8 months, DHA up close to 80%].
• Unsaturated fatty acids may generally reduce cholesterol.
  • By replacing saturated fats in the cell membranes.
  • Making the LDL receptor more efficient.
    • Primarily an LDL clearance effect.
• Unsaturated fatty acids “work” because they are more liquid than saturated fats.
  • Not an “animal” vs “plant” issue.
    • Saturated = animal = hard; unsaturated = plant = liquid.
    • Fish oil = animal = liquid…
• Omega-3 positively affects heart health:
  • Less stick blood platelets; anti-inflammatory; improves cellular metabolism (fluid membranes).
    • Not through impact on (lowering) triglycerides.
  • Most important: likely EPA + DHA.
    • EPA most studied, ALA and DHA less studied.
    • EPA and DHA have similar mechanisms (especially anti-inflammatory and platelet function).
  • DHA: may increase LDL cholesterol, impact of supplements on brain health is unclear.
• Omega-6: not as bad as people assume?
  • Meta analysis: the more LA eaten, the lower the risk of heart disease.
    • Less than 1% of LA gets converted to ARA.
  • Omega-6:omega-3 ratio may not be that important (similar for ARA:EPA ratio).
• Conclusion: increasing omega-3 intake (EPA+DHA) is key.
  • EPA + DHA % in red cell membranes (omega-3 index):
    • Average around 4-5%.
    • 8-12% ideal.
    • Ratio DHA to EPA about 85:15.
  • EPA + DHA dietary intake.
    • Average around 150 milligrams/day (EPA + DHA).
      • Okinaway = 2,000 milligrams; Inuits 6,000-7,000 milligrams.
  • If EPA + DHA go up, will automatically reduce ARA if it is too high.
    • Recommended to take EPA and DHA together.
    • Come together in most foods (salmon, herring, mackerel, etc.)
• 7/10.

Worth Listening

Interesting overview and discussion, perhaps not always as nuanced as prior podcasts.

Much of what we know about fatty acids has changed substantially over the last 20-30 years, so it may not make a lot of sense to make bold statements like there is no such thing as too much omega-3 (for instance, there is no mention of potential risks associated with higher omega-3 intake due to increased lipid peroxidation, higher free radicals, more cell damage, etc. – see “Fatty Acids“).

Also, statements on omega-6 were perhaps overly bold (“not as bad as people think” given how little is known about its impact. I think Attia rightly pushes back on Harris blanket statement on the increased risk for major diseases when the intake of omega-6 is lowered.

It would have been interesting to discuss potential benefits of GLA (omega-6) supplements in combination with EPA and DHA (see “Fatty Acids“).