Research

Mixed

Trans fat content in fast-food French fries declined to undetectable levels between 2006 and 2009 due to the phase-out of partially hydrogenated fats, whereas cheeseburgers remained a major source of trans fat due to natural ruminant fat.

You can likely find trans-fat-free French fries at major chains due to oil changes, but cheeseburgers still contain natural trans fats from beef. If you are strictly avoiding all trans fats, you must account for the natural content in meat products, not just processed oils.

GoodSupportsHIGH confidence
After the well-publicized shift from the use of partially hydrogenated fat between 2006 and 2009... the trans fat content of large French fries, per 1,000 kcal, declined to undetectable levels... Of the other menu items assessed, the major contributor of trans fat was cheeseburgers.
Lorien E. Urban et al. · Preventing Chronic Disease · 2014

Why this rating

Clear temporal trend identified via regression analysis over 14 years.

Source

Sodium, Saturated Fat, and<i>Trans</i>Fat Content Per 1,000 Kilocalories: Temporal Trends in Fast-Food Restaurants, United States, 2000–2013

Lorien E. Urban et al. · Preventing Chronic Disease · 2014

DOI 10.5888/pcd11.140335

cross_sectionalCited 16×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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