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SEED OILS

"Is there a seed oil in this?" — and our honest take

The Seed Oils module lets someone who wants to avoid seed oils instantly see whether a product contains one. It tags every oil into clear buckets. The most important thing to understand up front: this is a preference filter, not a health penalty — and that's a deliberate, evidence-based decision.

A filter, not a penalty — read this first

Seed oils are culturally controversial, but the current science (Johns Hopkins 2025, Memorial Sloan Kettering, recent meta-analyses) finds that at normal dietary doses they are mixed-to-neutral, not harmful. So we made a choice:

  • We flag seed oils so anyone avoiding them can filter and choose — respecting a real consumer preference.
  • We do not dock a product's health score just for containing a seed oil. The tag drives the UI filter only.
  • The genuinely evidence-backed fat concerns — trans fats and oxidation — are handled separately, on their own tags, because those do have harm evidence.

This keeps us honest: we serve the preference without overstating the science, and we don't punish a tin of tuna in sunflower oil as if it were a hot dog.

What counts as a seed oil — the "Hateful Eight"

Membership is the consumer cluster: high-PUFA, industrially refined (RBD), oxidation-prone seed oils — plus their refined, hydrogenated, and generic-blend variants.

Canola / Rapeseed Corn Cottonseed Soybean Sunflower Safflower Grapeseed Rice bran

"Vegetable oil" and generic blends count too (they're almost always one of the eight). A Partially Hydrogenated Soybean Oil is still tagged a seed oil and separately flagged for trans-fat risk — membership and evidence are kept on separate tracks.

Three separate questions, three independent tags

Fats get classified on three orthogonal axes — an oil can carry more than one. The UI composes them on read (e.g. "Avoid Concerning Fats" = seed oil OR palm OR tropical).

Seed Oil

The Hateful Eight + refined/hydrogenated/blend variants. High-PUFA, industrial.

Palm-derived

Every palm leaf — palm fruit, palm kernel, and blends. Saturated.

Tropical

Palm + coconut — saturated, oxidation-stable. Palm carries both palm and tropical tags.

What's not a seed oil — a common mix-up

People assume anything plant-based is a seed oil. We deliberately exclude these, with reasons documented so we never re-litigate them:

Olive — monounsaturated, traditionally pressed
Avocado — mesocarp (flesh), monounsaturated
Coconut / palm — saturated tropical (own tags)
Nut oils — almond, walnut, macadamia (specialty)
Specialty seed oils — chia, hemp, flax, pumpkin, sesame (artisan, not industrial RBD)
Animal fats & essential oils — fish, butterfat, flavorings

Look up any oil

Every oil we've classified and which tags it carries.

All oils we've reviewed from the Open Food Facts taxonomy. Search a name to see exactly how it's tagged — or whether it's deliberately not flagged.

OilTagsWhy

Where it's still rough (we'd rather you hear it from us)

  • It's an editorial line, not a hard fact. Open Food Facts has no "seed oil" flag — different sources draw the boundary differently. This is Peak Health's curated call (the "Hateful Eight" cluster), maintained by hand.
  • It rides on the ingredient list. If a label hides the oil behind "vegetable oil" with no detail, we tag the generic — but we can't always tell which seed oil it is.
  • The taxonomy drifts. Open Food Facts is volunteer-edited; new oil entries appear. We re-audit annually and the importer warns on any oil we haven't yet classified.
  • The science may move. Today we treat seed oils as a preference, not a penalty. If the evidence base shifts, the filter stays but the scoring stance is what we'd revisit.

Questions or disagreements on where the line sits? → tell Stefan and this page gets better.