Life Kit Episode Summary: "Are Seed Oils Really Bad for You? Researchers Unpack RFK Jr.'s Claims"

Release Date: July 31, 2025
Host: Marielle Segarra

Introduction

In this episode of Life Kit, hosted by Marielle Segarra, the focus is on the contentious topic of seed oils and their impact on health. The discussion is sparked by claims from Health Secretary Robert F. Kennedy, Jr., who alleges that seed oils like canola, sunflower, and soybean oil are detrimental to American health. To delve deeper into these claims, Marielle engages with NPR health correspondent Maria Godoy, who brings expert insights and research findings to the conversation.

Understanding Seed Oils

What Are Seed Oils?
Marielle initiates the conversation by seeking clarity on what constitutes a seed oil. Maria Godoy explains that seed oils, often referred to as vegetable oils, are extracted from the seeds of various plants. Common examples include canola, corn, safflower, soybean, cottonseed, sunflower, rice bran, and grapeseed oils. The extraction process typically involves refining methods using chemical solvents like hexane to maximize oil yield, contrasting with mechanical pressing methods used for oils like extra virgin olive oil.

Quote:
"Seed oils are typically refined, which means that producers use a chemical solvent, usually something called hexane, to extract the maximum amount of oil from the seed."
— Maria Godoy [03:16]

Alternatives to Seed Oils
Non-seed oils such as olive oil, avocado oil, and coconut oil are discussed as alternatives. However, Maria highlights concerns about the purity of some alternatives, noting that a 2020 study found that much of the avocado oil on the market was either rancid or adulterated with other oils.

Primary Concerns About Seed Oils

1. Hexane Residues from Refining

   The Issue:
   Critics argue that seed oils contain trace amounts of hexane, a chemical used in the refining process, which could pose health risks despite being removed during processing.

   Expert Insight:
   Maria cites a federal government report concluding that the residual hexane levels in seed oils are toxicologically insignificant. Furthermore, a researcher in fat and oil health effects mentions that residual hexane likely evaporates during cooking.

   Quote:
   "Toxicologists from the federal government have looked at this, and in a report published earlier this year, they concluded that the trace amounts of hexane residue in the seed oils we eat are toxicologically insignificant."
   — Maria Godoy [05:06]

   Recommendations:
   For those still concerned, Maria suggests opting for organic or cold-pressed seed oils, which do not contain hexane.

2. Omega-6 Fatty Acids and Inflammation

   The Debate:
   Seed oils are high in omega-6 fatty acids, which critics claim can lead to chronic inflammation—a risk factor for various diseases. Conversely, omega-3 fatty acids are known for their anti-inflammatory properties.

   Expert Viewpoint:
   Sarah Barry, a nutrition scientist, explains that while omega-6s can theoretically promote inflammation, real-world studies do not support this concern. In fact, omega-6 fatty acids can also have neutral or anti-inflammatory effects.

   Quote:
   "Now, that all looks beautiful on a piece of paper, but it doesn't play out in the human body. And there's randomized control trials consistently to support this."
   — Sarah Barry [08:22]

   Maria adds that randomized controlled trials have found no significant increase in inflammatory markers with higher seed oil consumption.

   Additional Insights:
   Tom Brenna, a fatty acids researcher, acknowledges that while excessive omega-6 intake might be a concern for individuals with certain genetic variations, the general population does not need to eliminate omega-6s. Instead, the focus should be on balancing omega-6 intake with sufficient omega-3s.

3. Seed Oils vs. Ultra-Processed Foods

   Core Issue:
   A prevalent criticism is that seed oils are prevalent in ultra-processed foods, which are linked to various health issues. The debate centers on whether the negative health outcomes are due to the seed oils themselves or the broader context of ultra-processed food consumption.

   Expert Consensus:
   Sarah Barry and Christopher Gardner both emphasize that ultra-processed foods contain multiple unhealthy components beyond seed oils, such as high levels of salt, sugar, and artificial additives. Therefore, it is misleading to attribute health problems solely to seed oils.

   Quote:
   "Is it the junk food that's causing these health issues or is it the seed oils? And I have always thought it's the junk foods."
   — Christopher Gardner [14:07]

Expert Recommendations

• Balanced Omega Intake:
  Nutrition experts advise maintaining a balanced intake of omega-6 and omega-3 fatty acids rather than eliminating omega-6s. Incorporating foods rich in omega-3s, such as fatty fish (e.g., salmon, mackerel), walnuts, flaxseeds, and chia seeds, is essential for health.

• Reducing Ultra-Processed Foods:
  A key takeaway is the importance of minimizing consumption of ultra-processed foods, which are the primary source of excessive omega-6 fatty acids and other unhealthy ingredients. Emphasizing whole foods like fruits, vegetables, lean proteins, and healthy fats contributes to better health outcomes.

• Choosing Quality Oils:
  For those concerned about seed oils, opting for high oleic varieties or non-refined oils like extra virgin olive oil can be a practical approach without the need for complete elimination.

Final Advice:
Marielle summarizes the expert opinions by reinforcing that seed oils, when consumed in moderation as part of a balanced diet, do not pose significant health risks. The overarching recommendation is to focus on reducing reliance on ultra-processed foods and incorporating a variety of whole, nutrient-dense foods into one's diet.

Conclusion

The episode effectively demystifies the controversy surrounding seed oils by presenting evidence-based perspectives from nutrition experts. It underscores the importance of a balanced diet and cautions against attributing health issues to a single type of food ingredient. By emphasizing moderation and informed choices, listeners are encouraged to navigate dietary decisions with confidence and clarity.

Notable Quotes:

• "Don't avoid them altogether because you need them for good health."
  — Maria Godoy [09:03]

• "This is one of the more studied topics in nutrition. So it's sort of extra bewildering to quite a few of us in the field that this is coming up."
  — Christopher Gardner [11:23]

• "Eating more seed oils doesn't lead to more of these inflammatory chemicals in people's bodies."
  — Maria Godoy [08:56]

For more insights on health and wellness, explore other episodes of Life Kit on topics like meal prepping and intuitive eating at npr.org/lifekit. If you enjoyed this episode and want additional content, consider subscribing to the Life Kit newsletter or sharing your feedback and episode ideas via email at us@lifekitpr.org.