Pie shell: a quarter fat by weight, and a trans fat story

The strongest study near this page tested an additive. A meta-analysis of 37 randomized trials, covering rice, noodles, pastry, bread and refined carbohydrates, found that 6 g of resistant maltodextrin blunted the blood glucose response by about 10% when baked into the food and about 20% in a drink (P < 0.001). Those were acute tests with for-profit authors involved, and none of them was a plain pie crust. A shop-bought crust is mostly fat and flour. Per 100 g, a frozen ready-to-bake enriched crust has 457 calories, 26.1 g fat of which 8.2 g saturated, and 409 mg sodium, from a single USDA record, and brands differ in whether that fat is butter, lard or shortening. A 9-inch shell weighs 6 oz (170 g) in US survey data, so one eighth of a pie carries about 21 g of crust, a figure made by division.

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• Per 100 g, a standard frozen ready-to-bake enriched pie crust has 457 calories, 26.1 g fat of which 8.2 g saturated, and 409 mg sodium. — USDA SR Legacy record Pie crust, standard-type, frozen, ready-to-bake, enriched (NDB 18334, FDC 175024) Evidence E source
  Per 100 g: energy 457 calories, fat 26.07 g, saturated fat 8.159 g, carbohydrate 48.62 g, sugars 3.72 g, fiber 2.5 g, protein 6.16 g, sodium 409 mg, iron 2.6 mg
• Across USDA pie crust records, sodium runs from 353 to 753 mg per 3.5 oz (100 g), and an unenriched frozen crust has 0.38 mg iron against 2.6 mg in the enriched one. — USDA SR Legacy pie crust records: deep dish frozen unbaked (FDC 167523), standard dry mix (175022), frozen ready-to-bake enriched (175024) and unenriched (175065) Evidence E source
  Sodium per 3.5 oz (100 g) 353 mg (deep dish frozen unbaked) to 753 mg (dry mix); iron 2.6 mg enriched vs 0.38 mg unenriched; thiamin 0.275 vs 0.05 mg

What a real portion looks like

• In US survey data a whole 9-inch pie shell weighs 6 oz (170 g) and a tart shell 25 g, so one eighth of a pie carries about 21 g of crust. — USDA FNDDS food code 53391000 Pie shell (FDC 2708017), portion weights Evidence E source
  1 pie shell (9 in) 170 g; 1 tart shell 25 g; quantity not specified 25 g; 1/8 of 170 g = 21 g (arithmetic)

What your body absorbs

• A meta-analysis of 37 RCTs found that adding a soluble fiber (resistant maltodextrin) to starchy foods including pastry cut the blood glucose response by about 10% in food and 20% in drinks. — healthy adults in 37 randomized placebo-controlled trials, foods with 30-173 g available carbohydrate (n = 37 trials) Evidence A source
  Glycemic response attenuated about 10% when 6 g RMD is in the food and about 20% in drinks (P < 0.001)
• In an acute double-blind RCT in healthy adults, a baked scone with type-4 resistant starch replacing refined flour cut the glucose response by 43 to 45%. — healthy adults, single high fiber RS4 scone vs low fiber control scone Evidence B source
  Glucose iAUC reduced 43-45%, insulin iAUC reduced 35-40%; glucose Cmax reduced 8-10%

What cooking and storage change

• Baking a pie crust raises its energy per 3.5 oz (100 g) by about 11 to 14% because water leaves, from 457 to 508 calories for a frozen crust and 445 to 506 calories for a refrigerated one. — USDA SR Legacy unbaked and baked pairs: frozen ready-to-bake enriched (FDC 175024 vs 175025), refrigerated regular (167932 vs 167930) Evidence E source
  Frozen: 457 to 508 calories, fat 26.07 to 28.59 g, sodium 409 to 467 mg per 3.5 oz (100 g); refrigerated: 445 to 506 calories, fat 25.46 to 28.69 g, sodium 409 to 472 mg per 3.5 oz (100 g)
• Palmitic acid in Greek savory pies rose between 2015 and 2021, by 3.5% in meat pies and 66.7% in vegetarian pies. — randomly selected savory baked goods from Athens, 2015-2021 Evidence C source
  Palmitic acid g/100 g up 3.5% (meat-containing pies) to 66.7% (vegetarian pies)

What it does to your health

• In an 8-week double-blind RCT, 79 healthy men eating bakery products carrying 20 g a day of trans fat from partially hydrogenated soy oil saw HDL cholesterol fall against control fat. — 87 healthy males randomized, 79 completed, 8 weeks (n = 79) Evidence B source
  HDL-C decreased in the trans fat group vs control; blood pressure, HRV and arterial measures unchanged

Safety, limits and interactions

• The FDA ruled in 2015 that partially hydrogenated oils, once the main source of artificial trans fat, are no longer generally recognized as safe, with a final compliance date of January 1, 2021. — US food supply Evidence E source
  PHOs not GRAS since 2015; no PHO additions after June 18, 2018 for most uses; final compliance January 1, 2021

Who this works differently for

• In 80,597 French women followed about 9 years, dietary acrylamide, to which pastries contribute, is linked to higher premenopausal breast cancer risk (HR 1.40 top vs bottom quartile). — 80,597 French females, mean follow-up 8.8 years (n = 80,597) Evidence C source
  Breast cancer overall HR Q4 vs Q1 1.21 (95% CI 1.00-1.47); premenopausal HR 1.40 (1.04-1.88); no association postmenopausal

What is still unknown

• In a crossover RCT in 31 healthy adults, adding 10 or 20 g of a potato resistant starch to a baked cereal bar did not lower the glucose response, so not every fiber swap in baked goods works. — 31 healthy adults, baked breakfast cereal bar with 0, 10 or 20 g RS4, 2-hour sampling (n = 31) Evidence B source
  No significant reduction in glucose or insulin iAUC (P > 0.05)
• A scoping review of 233 studies counted at least 690 label terms for fats that replaced trans fats, mostly in shortenings and margarines, and found health effects of the new fats poorly understood. — 233 studies (152 original, 81 reviews) on industrial trans fat substitutes (n = 233 studies) Evidence C source
  87 raw materials, palm stearin most frequent; at least 690 ingredient-list terms

The bottom line

Crust records vary. Sodium across the USDA pie crust records runs from 353 mg per 3.5 oz (100 g) in a deep dish frozen crust to 753 mg in a dry mix. An unenriched frozen crust has 0.38 mg iron per 3.5 oz (100 g) against 2.6 mg in the enriched one, and 0.05 mg thiamin against 0.275 mg, depending on the flour used. Baking raises energy per 3.5 oz (100 g) by about 11 to 14%, from 457 to 508 calories for a frozen crust and from 445 to 506 calories for a refrigerated one, because water leaves. Per whole crust the totals barely change. Trans fat is the old worry about crusts. In an 8-week double-blind trial, 79 healthy men ate bakery products carrying 20 g a day of trans fat from partially hydrogenated soy oil, and their HDL cholesterol fell compared with control fat, by an amount the abstract does not give. That dose is far above what US crusts carry today. The FDA ruled in 2015 that partially hydrogenated oils are no longer generally recognized as safe, with a final compliance date of January 1, 2021, though older crusts and some imports may differ. What replaced them is less studied. A scoping review of 233 studies counted at least 690 ingredient-list terms for trans fat substitutes, mostly in shortenings and margarines, and found limited understanding of their effects on health. In Athens, randomly bought savory pies had more palmitic acid in 2021 than in 2015, from 3.5% more in meat pies to 66.7% more in vegetarian pies, on the Greek market only and with no health outcome measured. Swapping flour for resistant starch in baked goods gives mixed results. In an acute double-blind trial in healthy adults, a scone made with type-4 resistant starch cut the glucose response by 43 to 45%, in a single meal whose abstract gives no sample size. In a crossover trial in 31 healthy adults, 10 or 20 g of a potato resistant starch in a baked cereal bar did not lower glucose or insulin significantly. The two used different starches in different foods, and neither has been repeated in a pie crust. The caution with numbers behind it is dietary acrylamide. In 80,597 French women followed for 8.8 years, the top quarter of dietary acrylamide intake was linked to higher premenopausal breast cancer risk (HR 1.40, 95% CI 1.04 to 1.88), with a borderline overall link (HR 1.21, 1.00 to 1.47) and none after menopause. That is observational, and the acrylamide came from all foods, with coffee, fries and chips, pastries, cakes and bread as the main sources. We have no card on wheat allergy or celiac disease for this page.

Sources

1. pshl-r5-01 · USDA SR Legacy composition, dataset
   Pie crust, standard-type, frozen, ready-to-bake, enriched (SR Legacy NDB 18334, FDC 175024), per 100 g: energy 457 kcal; total fat 26.07 g; saturated fat 8.159 g; carbohydrate 48.62 g; sugars 3.72 g; fiber 2.5 g; protein 6.16 g; sodium 409 mg; iron 2.6 mg
   USDA SR Legacy 2019, NDB 18334, FDC 175024 · checked 2026-09-30
2. pshl-r5-02 · USDA SR Legacy composition, dataset
   Per 100 g, SR Legacy: Pie crust, deep dish, frozen, unbaked, made with enriched flour (FDC 167523) sodium 353 mg; Pie crust, standard-type, dry mix (FDC 175022) sodium 753 mg; Pie crust, standard-type, frozen, ready-to-bake, enriched (FDC 175024) iron 2.6 mg, thiamin 0.275 mg; Pie crust, standard-type, frozen, ready-to-bake, unenriched (FDC 175065) iron 0.38 mg, thiamin 0.05 mg
   USDA SR Legacy 2019, FDC 167523, 175022, 175024, 175065 · checked 2026-09-30
3. pshl-r5-04 · USDA FNDDS portion weights, dataset
   Pie shell (FNDDS 53391000, FDC 2708017): 1 tart shell 25 g; 1 pie shell (9" dia) 170 g; Quantity not specified 25 g
   USDA FNDDS 2021-2023, food code 53391000, FDC 2708017 · checked 2026-09-30
4. pshl-r5-06 · meta-analysis of RCTs
   We found data from 37 relevant trials to April 2007. These trials investigated the attenuation of the glycemic response to rice, noodles, pastry, bread, and refined carbohydrates that included 30-173 g available carbohydrate. ... Attenuation of the glycemic response to starchy foods by 6 g RMD in drinks approached approximately 20%, but when placed directly into foods was approximately 10% -- significant (P < 0.001) by both modes of administration.
   Am J Clin Nutr, 2009 · checked 2026-09-30
5. pshl-r5-07 · RCT
   The fiber scone significantly reduced postprandial glucose and insulin incremental areas under the curves (43-45% reduction, 35-40% reduction, respectively) and postprandial glucose and insulin maximum concentrations (8-10% and 22% reduction, respectively).
   Nutrients, 2018 · checked 2026-09-30
6. pshl-r5-03 · USDA SR Legacy composition, dataset
   Per 100 g, SR Legacy: frozen ready-to-bake enriched unbaked (FDC 175024) 457 kcal, fat 26.07 g, sodium 409 mg; baked (FDC 175025) 508 kcal, fat 28.59 g, sodium 467 mg; refrigerated regular unbaked (FDC 167932) 445 kcal, fat 25.46 g, sodium 409 mg; baked (FDC 167930) 506 kcal, fat 28.69 g, sodium 472 mg
   USDA SR Legacy 2019, FDC 175024, 175025, 167932, 167930 · checked 2026-09-30
7. pshl-r5-11 · food composition survey
   An increase in PA content (in g/100 g product) was observed in most SBG types between 2015 and 2021, ranging from 3.5% in meat-containing pies to 66.7% in vegetarian pies, resulting in subsequent increased intakes.
   Eur J Nutr, 2025 · checked 2026-09-30
8. pshl-r5-05 · RCT
   In all, 87 healthy males included, 79 completed. INTERVENTION: Subjects were randomly assigned to 8 weeks of a daily intake of 33 g of experimental fats from either partially hydrogenated soy oil containing 20 g of TFA, 12 g of fish oil with approximately 4 g of n-3 PUFA and 21 g of control fat, or 33 g of control fat. The experimental fats were incorporated into bakery products. ... High-density lipoprotein cholesterol (HDL-C) decreased in the TFA group and triglycerides and mean arterial blood pressure decreased in the n-3 PUFA group compared to the control group.
   Eur J Clin Nutr, 2004 · checked 2026-09-30
9. pshl-r5-10 · agency position
   In 2015, the FDA took the significant step of determining that PHOs, then the major source of artificial trans fat in the food supply, are no longer 'Generally Recognized as Safe,' or GRAS.
   US FDA, Trans Fat, 2024 · checked 2026-09-30
10. pshl-r5-09 · cohort
    This prospective cohort study included 80,597 French females (mean ± SD age at baseline: 40.8 ± 14 y) during a mean ± SD follow-up of 8.8 ± 2.3 y. ... The mean ± SD dietary acrylamide intake was 30.1 ± 21.9 µg/d (main contributors: coffee, potato fries and chips, pastries, cakes, bread). ... A borderline significant positive association was observed between dietary acrylamide exposure and breast cancer risk overall (HR for quartile 4 compared with 1: 1.21; 95% CI: 1.00, 1.47) and a positive association was observed with premenopausal cancer (HRQ4vs.Q1: 1.40; 95% CI: 1.04, 1.88).
    Am J Clin Nutr, 2022 · checked 2026-09-30
11. pshl-r5-08 · RCT (crossover)
    The study was designed as a controlled, single-center randomized, single-blinded, cross-over trial, in which 31 healthy adults consumed a baked breakfast cereal bar containing 0, 10 or 20 g RS4 followed by serial blood samples over two hours to determine glucose and insulin concentrations and calculate the incremental area under the curve (iAUC). Results suggest that the addition of RS4 did not reduce iAUC glucose or insulin responses significantly (P > 0.05) at the doses provided.
    Food Funct, 2020 · checked 2026-09-30
12. pshl-r5-12 · scoping review
    Food items belonging to 15 food groups were found to contain trans fats substitutes, mainly margarine, shortenings, and spreads. From the collected data, it was estimated that there are at least 690 distinct terms for referring to industrial trans fats substitutes in the ingredients list. ... Furthermore, there is limited understanding of the short- and long-term effects of novel technological ingredients on human health.
    Nutr Rev, 2025 · checked 2026-09-30