Thoughts on Seed Oil

Original Article ↗ Hacker News Discussion ↗

Seed oils in processed foods are increasingly blamed for obesity, inflammation, and cancer, but commenters note that current human evidence is mixed and often overshadowed by clearer risks like inactivity, smoking, and excess calories. Many argue that focusing narrowly on seed oils distracts from broader dietary patterns—high intake of ultra-processed, calorie-dense, low‑nutrient foods—and from overall lifestyle factors. Others choose to avoid seed oils as a low-effort proxy for cutting processed foods, while emphasizing traditional fats (like olive oil or animal fats) and minimally processed, home‑cooked meals instead.

Seed oils vs overall diet quality

  • Many argue the main problem is the ultra-processed Western diet and excess calories, not seed oils specifically.
  • Others think seed oils may still matter, especially because they’re cheap, ubiquitous, and make junk food more profitable and abundant.
  • Several people treat “seed oil in the ingredients” as a practical proxy for “highly processed food to avoid.”

Frying, oxidation, and fat types

  • Disagreement over how important oil choice is for fried foods.
  • One side: reused seed oils at high heat degrade, oxidize, and possibly create more inflammatory byproducts than saturated fats.
  • The other side: typical fryer temps are below major trans-fat formation; the bigger issue is that fried foods are calorie-dense, low in nutrients and fiber, regardless of oil.
  • Some suggest that if only tallow were used, fried food would be pricier and less common.

Cholesterol, LDL, and saturated fat

  • Debate over whether raising LDL is clearly harmful.
  • Several commenters emphasize consensus that LDL/ApoB causally drive atherosclerosis and support medication plus diet.
  • Others claim the “high cholesterol scare” is overstated and note that dietary cholesterol itself is no longer seen as a major concern.
  • Concern is raised that swapping seed oils for saturated fats could worsen LDL.

Relative risks vs exercise and smoking

  • One line of discussion argues seed oils are a distraction compared with much larger risks like low fitness and smoking.
  • Others counter that people can address both exercise and diet, and that the hazard from seed oils is not quantified, so dismissing it outright is premature.
  • There is side discussion on smoking’s impact on BMI and whether smoking-related weight loss changes mortality risk (consensus: smoking still clearly worse overall).

Evidence and research ambiguity

  • Some point to rodent studies where high linoleic acid or unsaturated fat diets promote tumors, while saturated-fat diets do not.
  • Others respond that rodent cancer models and broader literature do not yet provide clear, directly applicable evidence that seed oils are dangerous for humans.
  • Overall sentiment: data on large harms from seed oils in humans is ambiguous; stronger evidence exists for harms from excess total fat, calories, and ultra-processed food.

Processed food, industry, and practical takeaways

  • Multiple comments stress that capitalism optimizes food for shelf life, cost, and palatability, not health.
  • Seed oils are framed by some as another “food bogeyman” in a long line of oversimplified villains.
  • Common practical stance: prioritize minimally processed foods, moderate all fats, exercise regularly; some personally avoid seed oils as a low-cost precaution, others see no strong reason to.