Cottonseed oil: lower LDL in a handful of industry-funded trials

Cottonseed oil lowers LDL cholesterol in the trials that exist, and very few exist. A 2024 systematic review found 2 randomized trials with 58 adults in total. In the 56-day one, with the oil supplying 30 percent of energy, LDL fell about 14 mg/dL more than on olive oil. Both trials were funded by the National Cottonseed Products Association and Cotton Incorporated. A newer 4-week trial in 91 adults with obesity or high cholesterol, mostly women, found LDL 11.7 and 12.9 mg/dL lower at 20 and 30 percent of energy from the oil than on a control oil blend. At 10 percent of energy the drop of 6.8 mg/dL did not reach significance (P = 0.08). These doses sit far above normal use, and a tablespoon of the oil weighs 14 g.

The numbers, per 3.5 oz (100 g)

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

How much is actually in it

• USDA lists cottonseed oil at 35.3 mg vitamin E and 25.9 g saturated fat per 3.5 oz (100 g), from a single legacy record with no measured spread. — USDA SR Legacy record Oil, cottonseed, salad or cooking (n = 1 record) Evidence E source
  Vitamin E 35.3 mg (235% DV), saturated fat 25.9 g, total fat 100 g per 3.5 oz (100 g)
• The UK table gives a second, independent figure: 42.77 mg vitamin E per 3.5 oz (100 g), 17% above USDA, with 50.1 g omega-6 and only 0.1 g omega-3. — CoFID 2021 food Oil, cottonseed, code 17-034 (n = 1 record) Evidence E source
  Vitamin E 42.77 mg; saturated 26.1 g; polyunsaturated 50.2 g (n-6 50.1 g, n-3 0.10 g); monounsaturated 18.3 g per 3.5 oz (100 g)

What a real portion looks like

• A tablespoon of cottonseed oil weighs 14 g in the US dietary survey, so the 27 g daily oil allowance used in modeling is about two tablespoons. — FNDDS food Cottonseed oil, code 82103000 Evidence E source
  1 tablespoon = 14 g; 1 cup = 224 g

What it does to your health

• A systematic review found only 2 trials with 58 adults. In the 56-day one, cottonseed oil lowered LDL cholesterol by about 14 mg/dL compared with olive oil. — Adults in 2 randomized trials (5 days and 56 days) where cottonseed oil supplied 44% or 30% of energy (n = 58) Evidence A source
  56-day trial vs olive oil: total cholesterol about -14.8 mg/dL, LDL-C about -14.0 mg/dL, non-HDL-C about -14.2 mg/dL
• In an RCT of 91 adults at cardiovascular risk, getting 20% or 30% of energy from cottonseed oil for 4 weeks lowered LDL cholesterol by 11.7 and 12.9 mg/dL versus a control oil blend. — Adults with obesity and/or hypercholesterolemia, 4-week partial outpatient feeding (n = 91) Evidence B source
  LDL-C -11.7 mg/dL (20% energy) and -12.9 mg/dL (30% energy) vs control; -6.8 mg/dL at 10% energy (P = 0.08)
• In an 8-week RCT of 43 adults with high cholesterol, a diet with 30% of energy from cottonseed oil cut LDL cholesterol by 19.7 mg/dL against 5.7 mg/dL with olive oil. — Men and women with hypercholesterolemia, 53 ± 10 years, 8-week partial outpatient feeding (n = 43) Evidence B source
  LDL-C -19.7 ± 3.94 vs -5.72 ± 4.23 mg/dL (P = 0.018); total cholesterol -17.0 vs -2.18 mg/dL
• In a crossover RCT of 15 healthy young men, 5 days on a cottonseed oil diet lowered TNF-alpha slightly more than olive oil, with no difference in IL-6 or CRP. — Fifteen normal-weight males, 21.7 ± 2.58 years, 5-day diets with 44% of energy from oil (n = 15) Evidence B source
  TNF-alpha -0.12 ± 0.02 vs -0.01 ± 0.05 pg/ml (p < 0.01); IL-6, CRP, PAI-1 no difference
• In a 28-day RCT of 91 adults at cardiovascular risk, subjective hunger fell at 10%, 20% and 30% of energy from cottonseed oil but not on the control oil blend. — Adults at risk of cardiovascular disease, 28-day parallel outpatient feeding, arms of 22-23 (n = 91) Evidence B source
  Hunger suppressed in all three oil doses (p < 0.01) vs control (p = 0.93); hormone responses inconsistent across doses

Safety, limits and interactions

• In the same 4-week RCT, body weight rose in all three cottonseed oil groups while it did not change in the control group. — 91 adults with overweight/obesity and/or hypercholesterolemia, 4 weeks (n = 91) Evidence B source
  Weight increased in LOW, MID and HIGH (P < 0.01, P = 0.01, P < 0.001) vs no change in control (P = 0.17)
• US food law caps free gossypol, the toxic pigment of cottonseed, at 450 ppm in cottonseed products allowed for human food. — Modified cottonseed products for human consumption (kernels and flours), 21 CFR 172.894 Evidence E source
  Free gossypol limit 450 ppm

What people believe that the data does not support

• The idea that omega-6 rich oil inflames the body was not borne out in an 8-week RCT of 42 adults: CRP, TNF-alpha, IL-6 and IL-1beta did not differ between cottonseed oil and olive oil. — 42 sedentary adults aged 30 to 75 with untreated hypercholesterolemia, 8 weeks, 30% of energy from the oil (n = 42) Evidence B source
  No between-group difference: CRP P = 0.70, TNF-alpha P = 0.98, IL-6 P = 0.21, IL-1beta P = 0.13

Who this works differently for

• The largest cottonseed oil trial so far enrolled almost only women: 81 of its 91 completers were female. — Completers of a 4-week dose-response RCT in adults at cardiovascular risk (n = 91) Evidence B source
  81 women and 10 men across four arms
• In 15 healthy normal-weight young men, 5 days of a high-fat diet rich in cottonseed oil lowered LDL cholesterol from 92.2 to 78.1 mg/dL, a within-group change. — Fifteen normal-weight men, randomized crossover, 5-day diets with 50% fat (n = 15) Evidence B source
  LDL-C 92.20 ± 5.57 to 78.13 ± 5.60 mg/dL; triglycerides 80.11 to 56.37 mg/dL (P < .05)

What is still unknown

• All of the eligible human trials on cottonseed oil and blood lipids were funded by cotton industry bodies, and together they enrolled 58 people. — Trials eligible for a 2024 systematic review, lasting 5 and 56 days (n = 58) Evidence A source
  2 trials (n = 15 and n = 43); funders National Cottonseed Products Association and Cotton Incorporated

The bottom line

Why the answer stays uncertain is simple. The two trials in the 2024 review were paid for by cotton industry bodies, and nobody has repeated them independently. In an 8-week trial of 43 adults with high cholesterol, LDL fell by 19.7 mg/dL on cottonseed oil against 5.7 mg/dL on olive oil. The 5-day crossover trial studied 15 healthy young men only, and their LDL went from 92.2 to 78.1 mg/dL, a within-group change over a very short diet. The worry that an omega-6 rich oil inflames the body was tested. In an 8-week trial of 42 adults with untreated high cholesterol, getting 30 percent of energy from cottonseed oil made no difference to CRP, TNF-alpha, IL-6 or IL-1beta compared with olive oil, a null result from a small sample and a secondary outcome. In the 15 young men, TNF-alpha fell by 0.12 pg/ml against 0.01 on olive oil, a tiny change of uncertain clinical meaning. Hunger ratings dropped at all three doses in the 4-week trial, while the hormones measured did not follow the dose. Per 100 g, USDA lists 35.3 mg vitamin E and 25.9 g saturated fat, from a single legacy record with no measured spread. The UK table gives 42.77 mg vitamin E, 50.1 g omega-6 and 0.1 g omega-3. Two cautions come from the records. In the 4-week trial body weight rose in all three cottonseed oil groups and did not change on the control blend, and the oil was added to the diet rather than swapped for other fat. US law caps free gossypol, the toxic pigment of cottonseed, at 450 ppm, but that rule covers kernel products and flours, and we found no separate limit for the refined oil. We have no card on allergy, pregnancy or medicines for this oil.

Sources

1. cto-r7-11 · USDA FoodData Central SR Legacy, dataset
   Oil, cottonseed, salad or cooking (FDC 171024, sr_legacy, Fats and Oils): vitamin E 35.3 mg per 100 g = 235% DV; saturated fat 25.9 g; fat 100 g; Foundation samples 0
   USDA FoodData Central, SR Legacy, FDC 171024 · checked 2026-09-28
2. cto-r7-12 · CoFID 2021, dataset
   Oil, cottonseed [17-034]: vitamin E 42.77 mg; Satd FA 26.10 g; Poly FA 50.20 g; n-6 poly 50.10 g; n-3 poly 0.10 g; Mono FA 18.30 g per 100 g
   CoFID 2021, Public Health England, code 17-034 (OGL v3.0) · checked 2026-09-28
3. cto-r7-13 · FNDDS, dataset
   Cottonseed oil, FNDDS 82103000 (fdc_id 2710184): 1 tablespoon = 14 g; 1 cup = 224 g
   USDA FNDDS, Cottonseed oil, code 82103000 (FDC 2710184) · checked 2026-09-28
4. cto-r7-01 · Systematic review of RCTs
   In total, 3 eligible publications (n = 2 trials), with 58 participants that provided 44% and 30% of total energy as CSO, were included. ... In a 56-day trial, CSO lowered total cholesterol (TC; ≈ -14.8 mg/dL), LDL-C (≈ -14.0 mg/dL), and non-high-density lipoprotein cholesterol (≈ -14.2 mg/dL) vs OO.
   Nutr Rev, 2024 · checked 2026-09-28
5. cto-r7-03 · RCT
   Low-density lipoprotein cholesterol reduced in MID and HIGH (-11.7 mg/dL and -12.9 mg/dL, respectively; P < 0.05 for both) with a trend for reduction in LOW (-6.8 mg/dL; P = 0.08) compared with no change in CON.
   J Nutr, 2026 · checked 2026-09-28
6. cto-r7-06 · RCT
   There were greater reductions from baseline to week 8 in fasting serum total cholesterol (TC; -17.0 ± 3.94 mg/dL compared with -2.18 ± 3.72 mg/dL, respectively; P = 0.008), LDL cholesterol (-19.7 ± 3.94 mg/dL compared with -5.72 ± 4.23 mg/dL, respectively; P = 0.018)
   J Nutr, 2022 · checked 2026-09-28
7. cto-r7-09 · RCT
   The CSO-enriched diets reduced TNF-α (CSO: -0.12 ± 0.02 pg/ml, OO: -0.01 ± 0.05 pg/ml; p < 0.01) and TF (CSO: -0.59 ± 0.68 pg/ml, OO: 1.13 ± 0.83 pg/ml; p = 0.02) compared to OO diets. There were no differences in IL-6, CRP, or PAI-1 between diets.
   Cytokine, 2024 · checked 2026-09-28
8. cto-r7-10 · RCT
   Subjective hunger was suppressed in LOW, MID, and HIGH (p < 0.01 for all) vs. CON (p = 0.93).
   Physiol Behav, 2026 · checked 2026-09-28
9. cto-r7-04 · RCT
   For body weight, there was a group × visit interaction (P = 0.01). Post hoc analyses revealed that this interaction was driven by increases in LOW, MID, and HIGH (P < 0.01, P = 0.01, P < 0.001, respectively) compared with no change in CON (P = 0.17).
   J Nutr, 2026 · checked 2026-09-28
10. cto-r7-14 · Regulation
    Free gossypol content not to exceed 450 parts per million.
    21 CFR 172.894, Modified cottonseed products intended for human consumption · checked 2026-09-28
11. cto-r7-08 · RCT
    RESULTS: There were no significant differences in fasting C-reactive protein (P = 0.70), tumor necrosis factor-α (P = 0.98), interleukin-6 (P = 0.21), interleukin-1β (P = 0.13), plasminogen activator inhibitor-1 (P = 0.29), or tissue factor (P = 0.29) between groups across the intervention.
    J Acad Nutr Diet, 2024 · checked 2026-09-28
12. cto-r7-05 · RCT
    Therefore, 91 participants completed the intervention (20 females and 3 males in the LOW group, 20 females and 3 males in the MID group, 20 females and 2 males in the HIGH group, and 21 females and 2 males in the CON group) and were included in this per-protocol analysis.
    J Nutr, 2026 · checked 2026-09-28
13. cto-r7-07 · RCT
    Fasting total cholesterol, low-density lipoprotein cholesterol, and triglycerides (TG) were lower following CSO diet intervention (total cholesterol: 148.40 ± 6.39 to 135.93 ± 6.31 mg/dL; low-density lipoprotein cholesterol: 92.20 ± 5.57 to 78.13 ± 5.60 mg/dL; TG: 80.11 ± 4.91 to 56.37 ± 5.46 mg/dL for pre- to postdiet, respectively; P < .05).
    Nutr Res, 2018 · checked 2026-09-28
14. cto-r7-02 · Systematic review of RCTs
    The 3 eligible publications (Table 2)10,25,26 reported results from 2 trials (durations of 5 days and 56 days) and had a total of 58 participants (n = 15 and n = 43 in each study, respectively). ... The studies included were funded by the National Cottonseed Products Association and Cotton Incorporated, with disclaimers that sponsors had no role in the design, implementation, data analysis, or interpretation of results.
    Nutr Rev, 2024 · checked 2026-09-28