Corn oil: lower LDL in short trials, no mortality benefit in the long one

Corn oil lowers LDL cholesterol in the short trials that tested it, and none of the trials we have shows that this turns into longer lives. The longest test is also the oldest. In the Minnesota Coronary Experiment, run from 1968 to 1973 among 9423 residents of a nursing home and six mental hospitals, a diet built on corn oil and corn oil margarine cut serum cholesterol by 13.8% against 1.0% in controls and showed no mortality benefit. That trial lost many participants, and later critics found discrepancies in its data. The modern trials are short and small. In 54 adults with high LDL, 4 tablespoons a day for 21 days lowered LDL by 10.9% against 3.5% on extra virgin olive oil, in a study funded by a corn oil maker. In a one-year trial in 251 Chinese adults with moderately high cholesterol, cooking at home with corn oil, peanut oil or a blended oil made no significant difference to blood lipids, glucose or CRP.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• Per 100 g, UK corn oil has 51.3 g polyunsaturated, 29.9 g monounsaturated and 14.4 g saturated fat with 17.2 mg vitamin E, while US Foundation samples give 22.6 mg vitamin E. — corn oil samples, UK and US (n = 5) Evidence C source
  Vitamin E 17.24 mg (CoFID) vs 22.6 mg (USDA Foundation, samples 18.6-25.2, n = 5); saturated fat 14.4 vs 13.4 g

What a real portion looks like

• In US dietary survey data, one tablespoon of corn oil weighs 14 g, about 126 calories. — US food portions (FNDDS) Evidence C source
  1 tablespoon 14 g; 1 cup 224 g; about 126 calories per tablespoon at 899 calories/100 g

What your body absorbs

• In a randomized crossover trial in 12 healthy adults, lycopene absorption from 5.3 oz (150 g) servings of tomato sauce was measured with 15 g of corn oil as the fat in each serving. — healthy subjects (n = 12, 6 men and 6 women), 150 g sauce with 15 g corn oil (n = 12) Evidence B source
  Lycopene AUC 870 (SEM 187) nmol.h/L from tangerine sauce

What cooking and storage change

• In 10 healthy adults, corn oil stripped of its natural phytosterols let 38% more cholesterol be absorbed than ordinary commercial corn oil. — healthy subjects, single test breakfasts with 30-35 g corn oil, n = 10 (n = 10) Evidence B source
  Cholesterol absorption +38.0% (SEM 10.2) with sterol-free vs commercial corn oil (P = 0.005)

What it does to your health

• In a double-blind crossover feeding trial in 54 adults with high cholesterol, 4 tablespoons of corn oil a day for 21 days cut LDL cholesterol by 10.9% versus 3.5% with extra virgin olive oil. — men and women (N = 54) with LDL-C 130 to 199 mg/dL, 21-day treatments, 21-day washout (n = 54) Evidence B source
  LDL-C -10.9% vs -3.5%; total-C -8.2% vs -1.8% (all P < .001); HDL-C no difference
• In a crossover trial in 25 adults with raised cholesterol, about 1.9 oz (54 g) of corn oil a day for 4 weeks lowered non-HDL cholesterol by 3.0% while coconut oil raised it by 5.8%. — 12 men and 13 women, mean age 45, LDL-C 115 to 189 mg/dL, 4 weeks per oil (n = 25) Evidence B source
  Non-HDL-C -3.0% vs +5.8% (P = 0.034); LDL-C -2.7% vs +4.6% (P = 0.06)
• In a crossover trial in 28 young men, 80 g a day of corn oil for two weeks lowered LDL cholesterol more than an olive and sunflower oil mix. — 28 healthy non-smoking men aged 19 to 31, two weeks per diet (n = 28) Evidence B source
  LDL-C fell significantly on corn oil (p < 0.01); TG and VLDL-TG lower than on mixed oil

Safety, limits and interactions

• In the STRENGTH trial of 13078 high-risk patients, corn oil used as the inert comparator had the same cardiovascular event rate as omega-3 capsules and fewer gut side effects (14.7% vs 24.7%). — 13078 statin-treated patients at high cardiovascular risk in 22 countries, 4 g/d capsules (n = 13078) Evidence B source
  Events 12.2% corn oil vs 12.0% omega-3 (HR 0.99, 0.90-1.09); GI adverse events 14.7% vs 24.7%

What people believe that the data does not support

• A meta-analysis of 16 trials found fish oil lowered triglycerides by 25.5 mg/dL compared with corn oil controls, with no difference in total or LDL cholesterol. — 16 randomized controlled trials with corn oil as control, 491 participants (n = 491) Evidence A source
  TG WMD -25.50 mg/dL (95% CI -42.44 to -8.57); HDL +2.54 mg/dL; TC and LDL no change
• In a crossover trial in 18 healthy adults, a 40 g fat meal with corn or flaxseed oil raised the inflammation marker GlycA slightly more than butter or coconut oil, with no consistent overall pattern. — 18 healthy adults, isocaloric 706 calories test meals with 40 g fat (n = 18) Evidence B source
  GlycA rose more after PUFA-rich meals (time x fat p < 0.001); no consistent direction across markers
• The EU rejected claims that corn oil, even with added vitamin E, helps control or maintain normal blood cholesterol. — EU food labeling Evidence E source
  Non-authorized

Who this works differently for

• Cohort data link linoleic acid intake of 9-16 g a day, about 2-3 tablespoons of corn oil, with 11% lower hip fracture risk. — nine prospective cohorts, 382094 participants, 12392 hip fractures, 7 to 24 years (n = 382094) Evidence C source
  Linoleic acid HR 0.89 (95% CI 0.82-0.96); saturated fat HR 1.20 (1.08-1.33)

What is still unknown

• In a one-year trial in 251 Chinese adults with moderately high cholesterol, cooking with corn oil, peanut oil or a blended oil made no difference to blood lipids, glucose or CRP. — 251 volunteers with total cholesterol 198 to 309 mg/dL (5.13 to 8.00 mmol/L), one year of home cooking oil (n = 251) Evidence B source
  No significant differences between oils in lipids, hsCRP, glucose, insulin
• In the Minnesota Coronary Experiment, a corn oil diet cut serum cholesterol by 13.8% but brought no mortality benefit, and a meta-analysis of 5 such trials in 10808 people found no drop in heart deaths. — 9423 women and men aged 20-97 in a nursing home and six mental hospitals; meta-analysis of 5 RCTs (n = 10808) (n = 10808) Evidence A source
  Cholesterol -13.8% vs -1.0%; CHD mortality RR 1.13 (0.83 to 1.54); all-cause 1.07 (0.90 to 1.27)

The bottom line

A tablespoon of corn oil weighs 14 g in US survey data and carries about 126 calories. Per 100 g, UK composition data give 51.3 g polyunsaturated, 29.9 g monounsaturated and 14.4 g saturated fat. The two national databases disagree on vitamin E by about a quarter, 17.2 mg in the UK figure against 22.6 mg across 5 US samples. Two more cholesterol trials point the same way with weaker footing. In 25 adults with raised cholesterol, about 54 g a day for 4 weeks lowered non-HDL cholesterol by 3.0% while coconut oil raised it by 5.8%. The LDL difference in that preliminary, manufacturer-funded study did not reach significance. In 28 young men, 80 g a day for two weeks lowered LDL significantly more than an olive and sunflower oil mix, which is far more oil than a normal day holds. Part of the effect sits in what refining leaves in the bottle. In 10 healthy adults eating a single test breakfast, corn oil stripped of its phytosterols in the laboratory let 38% more cholesterol be absorbed than ordinary commercial corn oil. Ordinary refining was not what they tested. The EU refused to authorize claims that corn oil, with or without added vitamin E, helps control blood cholesterol, which means the evidence fell short when it was assessed. Corn oil is also the usual dummy in fish oil trials. Across 16 such trials in 491 people, fish oil lowered triglycerides by 25.5 mg/dL more than corn oil (95% CI 8.6 to 42.4), with no difference in LDL. After a single 40 g fat meal in 18 healthy adults, corn or flaxseed oil raised the inflammation marker GlycA slightly more than butter or coconut oil, and nobody knows yet what that short rise means clinically. Pooled cohorts of 382094 people linked 9 to 16 g of linoleic acid a day, which the authors put at 2 to 3 tablespoons of corn oil, with an 11% lower risk of hip fracture (HR 0.89, 95% CI 0.82 to 0.96). That is an association from observational data. On caution, the only card concerns corn oil in capsules. In the STRENGTH trial of 13078 statin-treated patients at high heart risk, 4 g a day of corn oil used as the comparator had the same event rate as omega-3 capsules, 12.2% against 12.0%, with fewer gut side effects, 14.7% against 24.7%. We have no card on allergy, pregnancy or drug interactions for corn oil as a food.

Compared with other foods

Sources

1. cnol-daily-r6-12 · composition data
   Oil, corn 17-033 | Poly FA 51.30 g | Mono FA 29.90 g | Satd FA 14.40 g | Vitamin E 17.24 mg | Energy 899 kcal || Oil, corn FDC 748323 | Vitamin E 22.6 mg (samples 18.6-25.2, n=5) | Saturated fat 13.4 g
   CoFID 2021 (Public Health England), code 17-033; USDA FoodData Central Foundation, FDC 748323 · checked 2026-09-29
2. cnol-daily-r6-13 · portion data
   Corn oil | 1 tablespoon 14 g | 1 cup 224 g
   USDA FNDDS 2021-2023, food code 82102000 (fdc_id 2710183), Corn oil · checked 2026-09-29
3. cnol-daily-r6-06 · randomized crossover trial
   Sauces were served after 2 week washout periods and overnight fasting for breakfast to healthy subjects (n = 12, 6M/6F) in a randomized crossover design. The serving size was 150 g (containing 15 g of corn oil)
   J Agric Food Chem, 2007 · checked 2026-09-29
4. cnol-daily-r6-05 · randomized crossover trial
   Cholesterol absorption was 38.0 +/- 10.2% higher after consumption of the sterol-free corn oil than after consumption of commercial corn oil with an identical fatty acid content (P = 0.005; n = 10).
   Am J Clin Nutr, 2002 · checked 2026-09-29
5. cnol-daily-r6-01 · randomized crossover trial
   CO resulted in significantly larger least-squares mean % changes (all P < .001 vs EVOO) from baseline in LDL-C -10.9 vs -3.5, total-C -8.2 vs -1.8, non-HDL-C -9.3 vs -1.6, and total-C/HDL-C -4.4 vs 0.5.
   J Clin Lipidol, 2015 · checked 2026-09-29
6. cnol-daily-r6-02 · randomized crossover trial
   Changes from baseline for corn oil and coconut oil conditions, respectively, were: LDL cholesterol (primary outcome; -2.7% compared with +4.6%), non-HDL cholesterol (-3.0% compared with +5.8%)
   J Nutr, 2018 · checked 2026-09-29
7. cnol-daily-r6-04 · randomized crossover trial
   The PUFA-rich corn oil diet was able to reduce low density lipoprotein (LDL) cholesterol from adjustment to T2 significantly (p < 0.01), which was also confirmed by a trend after cross over (p=0.15).
   Eur J Nutr, 2001 · checked 2026-09-29
8. cnol-daily-r6-08 · randomized controlled trial
   The primary end point occurred in 785 patients (12.0%) treated with omega-3 CA vs 795 (12.2%) treated with corn oil (hazard ratio, 0.99 [95% CI, 0.90-1.09]; P = .84). A greater rate of gastrointestinal adverse events was observed in the omega-3 CA group (24.7%) compared with corn oil-treated patients (14.7%).
   JAMA, 2020 · checked 2026-09-29
9. cnol-daily-r6-09 · meta-analysis of RCTs
   The results revealed that the fish oil supplements significantly reduced TG (WMD: - 25.50 mg/dl, 95% CI: - 42.44, - 8.57, P = 0.000) levels compared to corn oil.
   Syst Rev, 2024 · checked 2026-09-29
10. cnol-daily-r6-10 · randomized crossover trial
    GlycA rose more after PUFA-rich meals (corn, flaxseed) than SFA-rich meals (butter, coconut), while IL-17C was higher after flaxseed oil.
    Clin Nutr ESPEN, 2026 · checked 2026-09-29
11. cnol-daily-r6-14 · EU health claim register
    POL-HC-6985 Corn Oil with a guaranteed polyunsatured fatty acids content (56% of total fatty acids), supplemented with vitamin E. 1- When used within a healthy, balanced diet, in combination with a healty lifestyle, corn oil with an elevated vitamin E content and a guaranteed polyunsaturates fatty acids content contributes to the control of blood cholesterol. 2-When used within a healthy, balanced diet, in combination with a healty lifestyle, corn oil contributes to the control of blood cholesterol. 3-As a part of a healthy lifesyle, corn oil helps to maintain normal blood cholesterol level.4-As a part of a healthy lifesyle, corn oil helps to keep blood cholesterol levels under control. Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6985, snapshot 2026-09-21 · checked 2026-09-29
12. cnol-daily-r6-11 · meta-analysis of cohorts
    These findings suggest that consuming 9-16 g of linoleic acid (LA) daily (equivalent to 2-3 tablespoons of corn oil or 30-60 g of walnuts) and maintaining elevated blood levels of omega-3 fatty acids, especially eicosapentaenoic acid (EPA), may help reduce the risk of hip fractures.
    Osteoporos Int, 2025 · checked 2026-09-29
13. cnol-daily-r6-03 · randomized controlled trial
    No significant differences were observed in the concentrations of fasting plasma lipids, hsCRP, glucose, and insulin among the three groups using different types of plant oils.
    Food Funct, 2020 · checked 2026-09-29
14. cnol-daily-r6-07 · meta-analysis of RCTs
    The intervention group had significant reduction in serum cholesterol compared with controls (mean change from baseline -13.8%v-1.0%; P<0.001). Kaplan Meier graphs showed no mortality benefit for the intervention group in the full randomized cohort or for any prespecified subgroup.
    BMJ, 2016 · checked 2026-09-29