Supplements · Metabolic & Cardiometabolic
ground flaxseed decreases LDL cholesterol
In plain terms: Does ground flaxseed lower bad cholesterol?
Strong support Supplements 🔬 Includes disconfirming
RefutedContestedStrong support
consensus score 0.60
Yes, in people with high cholesterol, but it must be ground not whole, and may slightly raise it in healthy people.
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
9 support 2 contradict 2 tested null 0 mixed · 13 sources, 11 independent groups
What the evidence shows
Ground flaxseed lowers LDL/TC/TG in dyslipidemic subjects (and HbA1c in T2D); paradoxically may raise LDL in healthy subjects. Highly bakeable; must be ground, not whole.
The evidence (16)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Akrami A, Nikaein F, Babajafari S, Faghih S, Yarmohammadi H 2018 · J Clin Lipidol | RCT | supports | moderate | RCT in metabolic syndrome: flaxseed oil lowered serum glucose and improved lipid profile vs sunflower oil |
| López-Toledo S, Pineda De la Cruz MC, Gutiérrez-Hurtado IA, Gijón-Soriano AL, Martínez-Martínez E, Valencia-Santiago C, Orellana-Centeno JE, Ramírez-García SA, Pacheco-Cruz R 2025 · Nutrients | RCT | tested-null | low | Parallel RCT in 166 Mexican T2D adults (n=82 intervention/84 control); 16 g/day flaxseed for 3 months significantly decreased total cholesterol and triglycerides (p<0.001) vs control. LDL not separately reported (TC used as lipid endpoint). |
| Sadat Masjedi M, Mohammadi Pour P, Shokoohinia Y, Asgary S 2022 · (SR/MA) | meta-analysis | supports | moderate | TC/LDL/TG significantly reduced in dyslipidemic (n=1107); LDL rose in healthy subgroup |
| Schoeneck M, Iggman D 2021 · Nutr Metab Cardiovasc Dis | meta-analysis | supports | high | Umbrella SR of 37 guidelines + 108 SRs/MAs + 20 RCTs, GRADE-rated (search to June 2019): 'Soy protein, tomatoes, flaxseeds, and almonds caused small reductions' in LDL-C, within the high-evidence tier. SMALL means below the paper's own moderate band of 0.20-0.40 mmol/L, and the abstract says 'flaxseeds' without distinguishing ground from whole seed. Abstract-grade read; per-food GRADE table not obtained. |
| Musazadeh V, Nezamoleslami S, Faghfouri AH, Shidfar F, Aryaeian N 2025 · Diabetes Metab Syndr | meta-analysis | contradicts | moderate | Random-effects MA of 16 RCTs (1136 diabetic patients). Clean null on LDL-C: SMD -0.09 (95% CI -0.87 to 0.70), p=0.830, I2=96.3%; authors: flaxseed 'does not suggest any benefit on blood pressure and other lipid profile parameters' (only weight, waist and triglycerides improved). Diabetic, not dyslipidemic, population; whether ground seed was separated from flaxseed oil or lignan is not stated in the abstract. |
| Hadi A, Askarpour M, Salamat S, Ghaedi E, Symonds ME, Miraghajani M 2020 · Pharmacol Res | meta-analysis | supports | high | 62-RCT dose-response: flaxseed lowers LDL-C, TC, TG |
| Yang C, Xia H, Wan M, Lu Y, Xu D, Yang X, Yang L, Sun G 2021 · Nutr Metab (Lond) | meta-analysis | supports | high | Dose-response MA: whole flaxseed (not oil) significantly reduced LDL-C and TC in dyslipidemia-related disease; lignans contribute |
| Mohammadkhani N, Moradnia M, Mohammadi M, Ebrahimpour S, Tabatabaei-Malazy O, Mirsadeghi S, Javar HA 2025 · Journal of diabetes and metabolic disorders | observational | supports | low | Narrative review (2,412 articles screened) of flaxseed's antioxidant/anti-inflammatory effects concludes clinical and animal studies show flaxseed and derivatives exhibit antihyperlipidemic properties, without reporting a specific LDL/TC de |
| Błaszczuk A, Barańska A, Kanadys W, Malm M, Jach ME, Religioni U, Wróbel R, Herda J, Polz-Dacewicz M 2022 · Nutrients | meta-analysis | supports | moderate | MA in postmenopausal women: flaxseed lowered TC and LDL-C vs soy/red clover |
| Pan A, Yu D, Demark-Wahnefried W, Franco OH, Lin X 2009 · Am J Clin Nutr | meta-analysis | supports | high | Landmark MA: whole flaxseed lowered LDL-C (-0.10 mmol/L) and TC; effect stronger in women and hypercholesterolemic subjects |
| Sabet HR, Ahmadi M, Akrami M, Motamed M, Keshavarzian O, Abdollahi M, Rezaei M, Akbari H 2024 · Clin Cardiol | meta-analysis | tested-null | low | SR+MA of 6 RCTs (all Iran) in coronary artery disease; LDL-c pooled from 4 trials: WMD +0.12 mg/dL (95% CI -6.74 to 6.98; I2 5.7%), a clean null; TC -2.72 (-11.31 to 5.87). The stored 'reduced LDL-C' was wrong. Exposure pools flaxseed oil (Saleh-Ghadimi 5 g oil, Raygan 1000 mg oil, Talari oil + vitamin D) with one ground-seed trial (Khandouzi 2022, 30 g/d); no seed-only LDL estimate. Significant only for FBS -8.35 (-15.01 to -1.69) and hs-CRP -1.35 (-1.93 to -0.77). GRADE certainty for LDL: low. |
| Schwingshackl L, Bogensberger B, Benčič A, Knüppel S, Boeing H, Hoffmann G 2018 · J Lipid Res | meta-analysis | supports | high | Network MA of oils/fats: flaxseed/linseed oil ranked favorably for lowering LDL-C among fat sources |
| Jaček M, Hrnčířová D, Rambousková J, Dlouhý P, Tůma P 2020 · Nutrients | RCT | tested-null | low | 2-mo low-dose n-3 (flaxseed-fed meat/eggs) RCT: no significant change in plasma cholesterol, LDL or HDL |
| Yin S, Xu H, Xia J, Lu Y, Xu D, Sun J, Wang Y, Liao W, Sun G 2023 · Adv Nutr | meta-analysis | contradicts | moderate | ALA MA in overweight/obese: ALA (mainly flaxseed) SIGNIFICANTLY INCREASED LDL-C (+1.32 mg/dL) though cut TG/CRP/SBP |
| Lenártová P, Gažarová M, Kopčeková J, Mrázová J 2024 · Life (Basel, Switzerland) | RCT | supports | low | RCT in 51 menopausal women given 40 g/day crushed (ground) flaxseed (high- vs low-lignan variety) for 8 weeks vs control; LDL-C significantly decreased in both flaxseed groups, but total cholesterol and HDL-C significantly increased. |
| Mirfatahi M, Tabibi H, Nasrollahi A, Hedayati M 2016 · Iran J Kidney Dis | RCT | supports | moderate | RCT in hemodialysis patients: flaxseed oil reduced LDL-C and triglycerides vs control |
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