In this episode, Dr. Kate Kresge welcomes back Dr. Eric Viegas to talk about one of the most widely recommended supplements on the market: omega-3s. Omega-3s are studied for cardiovascular health, inflammation, and cognition, but their benefits depend on what's actually in the capsule. (ODS n.d.) Dr. Viegas explains how oxidation is measured, why label claims for EPA and DHA sometimes fall short, what molecular distillation does (and doesn't yet address), and how ingredient form affects absorption. He also shares how Fullscript spot-tests fish oils pulled straight from its distribution center. You'll leave knowing exactly what to look for on the label, and what to ask the brand.
3 Key Takeaways
- Oxidation is measurable. Peroxide value reflects primary oxidation, p-anisidine value reflects secondary oxidation, and TOTOX combines the two. (Jairoun 2020) Dr. Viegas notes that flavorings like rosemary extract can interfere with p-anisidine testing in finished products. (Bannenberg 2017)
- Label claims deserve verification. In one survey of retail fish oils in New Zealand, most products contained less EPA and DHA than labeled. (Albert 2015) Dr. Viegas explains how lab methods and handling can also affect results. (Bannenberg 2017)
- Form affects absorption. In a 72-person trial, re-esterified triglyceride fish oil showed greater EPA and DHA bioavailability than ethyl ester forms. (Dyerberg 2010)
Guest: Dr. Eric Viegas is a naturopathic doctor and Medical Product Manager at Fullscript, where he leads initiatives on supplement quality, safety, and education. He works closely with brands and third-party labs to evaluate potency, purity, and manufacturing standards across the Fullscript catalog.
Clinical FAQ
Which omega-3 form should I choose for patients with digestive issues?
Dr. Viegas notes that ethyl ester forms require more digestive processing, so triglyceride or monoglyceride forms may be better options for patients with GI concerns or pancreatic insufficiency. (Cuenoud 2020)
What should a good fish oil smell like?
Not like fish. A strong fishy smell or taste suggests rancidity. He recommends refrigerating liquids, avoiding temperature swings, and using an opened bottle within about 120 days.
Which certifications matter for fish oil?
He points to GOED standards for oxidation, potency, and purity, and IFOS, which rates products and lets you look up results by lot number.
Timestamps
– Introduction and benefits of omega-3s
– Fullscript's quality initiatives for omega-3s
– How oxidation affects supplement quality
– Peroxide and p-anisidine values
– Omega-3 forms: pros and cons
– EPA and DHA label accuracy
– Heavy metals, microplastics, PCBs, and PFAS
– Small fish and molecular distillation
– "Pharmaceutical grade," "purified," and "professional grade"
– Label indicators and storage
– At-home storage tips
– Fullscript's testing protocols
– Direct-from-manufacturer sourcing and counterfeits
– Myths and key certifications
– Questions to ask before buying
Ready to elevate your practice? This episode is sponsored by Fullscript https://fullscript.com/?utm_campaign=rootcausemedicinepodcast&utm_medium=podcast&utm_source=fullscript-academy, a comprehensive care delivery platform designed to support whole-person, integrative healthcare. Fullscript helps clinicians bring supplement dispensing, lab ordering, and patient education into one centralized workflow. For more practitioner education on supplements, nutrition, and evidence-informed clinical care, visit Fullscript Academy at academy.fullscript.com.
Disclaimer: The views expressed on this podcast are those of the hosts and guests and don’t necessarily reflect those of Fullscript or any affiliated organizations. This podcast is for informational and educational purposes only and is not intended to be medical advice. For your safety, always check with your doctor or healthcare provider before making changes to your health routine.
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