Flaxseed (Linum usitatissimum) and flaxseed oil, which comes from flaxseed, are rich sources of the essential fatty acid alpha-linolenic acid — a heart-healthy omega-3 fatty acid. Flaxseed is high in soluble fiber and in lignans, which contain phytoestrogens. Similar to the hormone estrogen, phytoestrogens might have anti-cancer properties. Flaxseed oil doesn't have these phytoestrogens.
Flaxseed can be used whole or crushed, or in a powder form as meal or flour. Flaxseed oil is available in liquid and capsule form.
People use flaxseed and flaxseed oil to reduce cholesterol and blood sugar and treat digestive conditions. Some people also take flaxseed to treat inflammatory diseases.
Research on the use of flaxseed and flaxseed oil for specific conditions shows:
- Heart disease. Some studies suggest that alpha-linolenic acid, which is found in flaxseed and flaxseed oil, might benefit people with heart disease. Early research also suggests that flaxseed might help lower high blood pressure, which plays a role in heart disease.
- Cholesterol levels. Several studies show that taking flaxseed daily can reduce total cholesterol and low-density lipoprotein (LDL, or "bad") cholesterol levels. However, other studies aren't as favorable.
- Diabetes. Taking flaxseed might lower blood sugar levels in people with type 2 diabetes. However, the same results haven't been found for flaxseed oil.
- Menopausal symptoms. Results have been mixed when it comes to use of flaxseed and the treatment of menopausal symptoms.
When used in combination with daily exercise and a low cholesterol diet, flaxseed might help control cholesterol levels. Flaxseed might also be helpful for managing diabetes and lowering the risk of heart disease.
Oct. 25, 2017
- Flaxseed and flaxseed oil. National Center for Complementary and Integrative Health. https://nccih.nih.gov/health/flaxseed/ataglance.htm. Accessed Sept. 27, 2017.
- Flaxseed reduces some risk factors of cardiovascular disease. National Center for Complementary and Integrative Health. https://nccih.nih.gov/research/results/spotlight/062308.htm. Accessed Sept. 27, 2017.
- Flaxseed oil. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Sept. 27, 2017.
- Flaxseed. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Sept. 27, 2017.
- Khalesi S, et al. Flaxseed consumption may reduce blood pressure: A systematic review and meta-analysis of controlled trials. Journal of Nutrition. 2015;145:758.