Omega Polyunsaturated Fats in Inflammation | Philip Calder | Episode 291

Send us Fan Mail

How dietary fatty acids regulate the initiation, propagation, and resolution of inflammation.

TOPICS DISCUSSED:

• Parenteral nutrition history: IV nutrition evolved from soybean oil alone in the 1960s to complex blends including fish oil as the biology of ω-3s became understood.
• Three phases of inflammation: Initiation, propagation (driven by ω-6–derived prostaglandins and leukotrienes), and active resolution (driven by ω-3-derived resolvins and protectins).
• Pro-resolving mediators: Resolution is an active biological process, not passive; EPA and DHA generate resolvins and protectins that actively terminate inflammation.
• Aspirin’s ω-3 mechanism: Aspirin inhibits arachidonic acid metabolism but allows EPA/DHA to access COX-2, upregulating pro-resolution mediators — a likely underappreciated mechanism of action.
• Cell membrane competition: EPA and DHA physically displace arachidonic acid in membranes, shifting the balance of mediators produced and improving resolution capacity.
• Linoleic acid & EPA synthesis: High linoleic acid intake saturates shared desaturase enzymes, inhibiting the body’s conversion of ALA to EPA — meaning reducing ω-6 can raise ω-3 levels without supplementation.
• Dose & timing of ω-3 incorporation: ~2g/day of EPA+DHA shifts the arachidonic acid-to-EPA ratio enough to measurably reduce prostaglandin E2 production; white blood cells reflect changes within a month.

ABOUT THE GUEST: Philip Calder, PhD is Professor of Nutritional Immunology in the Faculty of Medicine at the University of Southampton. His research focuses on how dietary fatty acids — particularly omega-3s — modulate immune responses and inflammatory processes across clinical and healthy populations.

RELATED EPISODE:

• M&M 200: Dietary Fats & Seed Oils in Inflammation, Colon Cancer & Chronic Disease | Tim Yeatman & Ganesh Halade

Support the show

Support my work:

• Good Chemistry: Personalized, science-based health consulting. Work with Dr. Nick Jikomes directly.
• Affiliate Partners: Visit this link to see my affiliate partners and get discounts codes for products & services to support health.

For all the ways you can support my efforts.