ALSOFOUNDINPartially Hydrogenated Oils (PHOs)
US Ban · 2018Denmark banned it in 2003. America finished in 2018. Also listed on labels as PHOs, Trans fat, Industrial trans fatty acids, Hydrogenated oil.
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What it is
Liquid vegetable oil forced to react with hydrogen until it turns semi-solid — a process that creates industrial trans fats as a byproduct. It was invented to make cheap shelf-stable shortening, and for most of the 20th century it was marketed as the healthy alternative to butter and lard.
Why it's in food
It was extraordinary at its job: solid at room temperature, nearly immortal on a shelf, cheap, and perfect for frying and flaky baked goods. That performance is why it took decades to remove even after the science was settled.
US vs EU status
United States
Banned — the FDA revoked GRAS status for PHOs in 2015, with compliance deadlines running through 2018 for most uses and into 2021 for the last. The remaining problem isn't the oil, it's the label: US rules let a product declare '0g trans fat' if it contains less than 0.5 grams per serving. Small servings, repeated, still add up, and naturally occurring trans fats in meat and dairy are unaffected.
European Union
Denmark went first, in 2003, capping industrial trans fat at 2% of fats — the first country in the world to act, and the model everyone else eventually copied. The EU adopted the same 2% cap across all member states in April 2021. Europe regulates by limit rather than by outright revocation; the practical result is the same.
Common products
- Historically: margarine, shortening, and fryer oil
- Packaged cookies, crackers, pie crusts, and frosting
- Microwave popcorn and non-dairy creamer
- Fast food fryers before the mid-2000s
- Today: should be gone — check for 'partially hydrogenated' on older or imported stock
- Still permitted: '0g trans fat' labels on products under 0.5g per serving
Cleaner swaps
- Butter, olive oil, or plain vegetable oils
- Fully hydrogenated oils — no trans fat, though usually blended
- Products listing the actual oil by name
Case note
This is the file where nobody argues about the science — trans fat's harm was settled while it was still in every fryer in America. Denmark acted in 2003. The last US deadline landed in 2021. Eighteen years, one uncontested finding. Every other file on this board is slower than this one, and this one is the fast case.
FAQ
Are trans fats gone from American food?
Industrial ones essentially are — PHOs lost their legal standing in 2015 and the last compliance deadlines have passed. What remains is small: trace amounts under the 0.5g labeling threshold, trans fats naturally present in meat and dairy, and mono- and diglycerides, which can contain trans fat and don't count toward the fat lines at all.
What does '0g trans fat' actually mean?
It means under 0.5 grams per serving — not zero. The serving size is where the trick lived: shrink it enough and almost anything rounds down. It mattered far more before the ban, but it's still the single most useful thing to understand about how the Nutrition Facts panel is constructed.
Why did it take the US so long?
The science wasn't the holdup — the link between industrial trans fat and heart disease was clear by the 1990s, and Denmark acted on it in 2003. What followed here was labeling first, in 2006, then reformulation pressure, then a 2015 revocation with deadlines into 2018 and beyond. Fifteen years between the first country acting and the last deadline landing.
What replaced them?
Palm oil, fully hydrogenated oils blended back into liquid oils, and interesterified fats — a newer process with a thinner research record. That's the pattern worth watching across this whole board: removals create replacements, and replacements start their files at zero.
How the FDA decides what reaches your table and your medicine cabinet — and how it learned to decide.
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