Introduction

Flaxseed oil comes from the tiny seeds of the flax plant. It has been used to promote heart health and lower blood pressure. Flaxseed oil is high in omega-3 fatty acids, a fat your body needs to promote wellness. Flaxseed oil can be taken orally or used in cooking. It can also be taken as a pill or applied to the skin.

Dosages

1 to 2 tablespoons daily

What Research Shows

Likely Effective

  • High blood pressure —likely to lower diastolic blood pressure F1, F2

May Be Effective

  • Carpal tunnel syndrome —may ease symptoms and improve function C1
  • Diabetic foot ulcer —may promote wound healing D1
  • Diabetic neuropathy —may improve insulin and triglyceride levels E1
  • Lipid profile —may raise HDL (“good”) cholesterol in older adults H1
  • Polycystic ovary syndrome —may lower LDL (“bad”) cholesterol and triglycerides I1, I2

Unlikely to Be Effective

  • Hyperlipidemia —unlikely to lower LDL (“bad”) cholesterol; likely to lower when taken as flax-seed G1

Not Enough Data to Assess

  • Bipolar disorder in children A1
  • Cardiovascular disease B1

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Safety Notes

It is likely safe to take flaxseed oil in small doses for a short time, but allergic reactions may happen.J1 Not enough studies have been done to say whether it is safe to take for a long period. It is also not known whether it is safe to take by women who are pregnant or breastfeeding.

Interactions

Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse.

 

References

A. Bipolar Disorder in Children

A1. Gracious BL, Chirieac MC, et al. Randomized, placebo-controlled trial of flax oil in pediatric bipolar disorder. Bipolar Disord. 2010 Mar;12(2):142-154.

B. Cardiovascular Disease

B1. Abdelhamid AS, Brown TJ, et al. Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2018;7:CD003177.

C. Carpal Tunnel Syndrome

C1. Hashempur MH, Homayouni K, et al. Effect of Linum usitatissum L. (linseed) oil on mild and moderate carpal tunnel syndrome: a randomized, double-blind, placebo-controlled clinical trial. Daru. 2014;22:43.

D. Diabetic Foot Ulcer

D1. Soleimani Z, Hashemdokht F, et al. Clinical and metabolic response to flaxseed oil omega-3 fatty acids supplementation in patients with diabetic foot ulcer: A randomized, double-blind, placebo-controlled trial. J Diabetes Complications. 2017 Sep;31(9):1394-1400.

E. Diabetic Nephropathy

E1. Soleimani A, Taghizadeh M, et al. Metabolic response to omega-3 fatty acid supplementation in patients with diabetic nephropathy: A randomized, double-blind, placebo-controlled trial. Clin Nutr. 2017 Feb;36(1):79-84.

F. High Blood Pressure

F1. Khalesi S, Irwin C, et al. Flaxseed consumption mat reduce blood pressure: a systematic review and meta-analysis of controlled trials. J Nutr. 2015;145(4):758-765.

F2. Ursoniu S, Sahebkar A, et al. Effects of flaxseed supplements on blood pressure: A systematic review and meta-analysis of controlled clinical trial. Clin Nutr. 2016;35(3):615-625.

G. Hyperlipidemia

G1. Pan A, Yu D, et al. Meta-analysis of the effects of flaxseed interventions on blood lipids. Am J Clin Nutr. 2009;90(2):288-297.

H. Lipid Profile

H1. Avelino AP, Oliveira GM, et al. Additive effect of linseed oil supplementation on the lipid profiles of older adults. Clin Interv Aging. 2015 Oct 22;10:1679-1685.

I. Polycystic Ovary Syndrome

I1. Ebrahimi FA, Samimi M, et al. The Effects of Omega-3 Fatty Acids and Vitamin E Co-Supplementation on Indices of Insulin Resistance and Hormonal Parameters in Patients with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Exp Clin Endocrinol Diabetes. 2017 Jun;125(6):353-359.

I2. Mirmassoumi G, Fazilati M, et al. The Effects of Flaxseed Oil Omega-3 Fatty Acids Supplementation on Metabolic Status of Patients with Polycystic Ovary Syndrome: A Randomized, Double-Blind, Placebo-Controlled Trial. Exp Clin Endocrinol Diabetes. 2018;126(4):222-228.

J. Safety

J1. Alonso L, Marcos ML, et al. Anaphylaxis caused by linseed (flaxseed) intake. J Allergy Clin Immunol. 1996 Aug;98(2):469-470.

Last reviewed July 2019 by EBSCO NAT Review Board Eric Hurwitz, DC  Last Updated: 5/6/2020