A Natural Experiment Shows the Payoff
Between 2007 and 2011, eleven New York counties restricted industrial trans fats, while twenty-five similar counties did not. That policy split created a rare “natural experiment.” An analysis of hospitalizations from 2002–2013, published in JAMA, found that three years after restrictions, the trans-fat–limited counties experienced a 6.2% greater decline in combined heart-attack and stroke admissions than the unrestricted counties. In plain terms: tighten trans fat rules, and serious cardiovascular events drop. With nationwide restrictions rolling out, this is exactly the trajectory public health hoped for.
How We Got Here: FDA Actions and Intake Trends
For two decades the FDA has been ratcheting down industrial trans fats. Removing them from the GRAS list in 2013 and setting a phase-out target accelerated reformulation across the food supply. The agency estimates consumer intake fell by roughly 78% from 2003 to 2012. Independent blood-based evidence reinforces that trend. In a Framingham Offspring substudy, the Trans Fat Index (TFI—red-blood-cell C18:1t + C18:2n6t) slid from 2.5% in 1999 to 1.9% in 2006. That population didn’t change diets en masse; the food landscape changed around them.
Blood Levels Keep Dropping—But Not Everywhere, Not Yet
OmegaQuant’s own databases tell a similar story. Pooling more than 13,000 tests per year from 2009–2014, average TFI fell about a third in both dried blood spot and red blood cells, approaching—but not quite reaching—our desirable threshold. By 2014, the typical American’s TFI hovered just above 1.0%, meaning half the population was still above target even as the average neared it. The national ban should keep nudging that curve lower, but there remains room—and reason—to act at the individual level.
What’s “Good Enough”? A Target Emerges
A large German cohort (LURIC) followed more than 3,200 patients for a decade. Those with a red-blood-cell TFI below 1% did not show increased cardiovascular risk attributable to industrial trans fats. Notably, a naturally occurring dairy fat, trans-palmitoleic acid (C16:1n-7t), tracked with better outcomes—reminding us that “trans fat” is not a single molecule and that industrially produced species are the ones of concern. Taken together, these data support a practical goal: keep TFI under 1%.
Why Trans Fats Haven’t Disappeared From Your Pantry
Labels can lull you. Since 2006, Nutrition Facts panels must list trans fat per serving—but anything under 0.5 g can be rounded down to “0 g.” Shrink the serving size, and a product can legally claim zero while still delivering a meaningful dose in real-world portions. The ingredient list is your backstop: “partially hydrogenated” oils are the giveaway that industrial trans fats are present. Until the phase-out is fully complete, typical culprits include shelf-stable baked goods, frostings, microwave popcorn, certain margarines and shortenings, non-dairy creamers, and some refrigerated doughs.
Practical Steps While the Ban Finishes Working
Shop like a skeptic. Scan ingredients for “partially hydrogenated,” even when the front of pack trumpets “0 g trans fat.” Favor brands that reformulated early; many did. Cook and bake with unhydrogenated oils, and lean on minimally processed foods where trans fats were never part of the picture. If you’re curious where you stand personally, a red-blood-cell fatty-acid test can quantify TFI alongside other lipids you may already track.
The Bottom Line
Policy moved first, manufacturers followed, blood levels fell—and now hard outcomes are catching up. The New York county data link trans-fat restrictions to fewer heart attacks and strokes, and the European risk threshold aligns with a TFI of less than 1%. We’re close, but not done. Keep reading labels, avoid partially hydrogenated oils, and let the last pockets of trans fat age out of the food system. Your arteries will notice.
