Flax is a food and fiber crop that grows in Europe, Asia, and the Mediterranean. Flaxseeds are the golden yellow to reddish brown seeds of flax. These seeds contain phytoestrogens, which are similar to the hormone estrogen, as well as soluble fiber and oil. Flaxseed oil contains the essential omega-3 fatty acid alpha-linolenic acid (ALA). Flaxseed has been eaten as a food or used as a medicine since 5000 BC.
People use flaxseed by mouth for constipation, colon damage due to overuse of laxatives, diarrhea, inflammation of the lining of the large intestine (diverticulitis), irritable bowel syndrome (IBS) or irritable colon, sores in the lining of the large intestine (ulcerative colitis), inflammation of the lining of the stomach (gastritis), and inflammation of the small intestine (enteritis).
People also take flaxseed by mouth used for disorders of the heart and blood vessels, including heart disease, high triglyceride levels, high cholesterol, “hardening of the arteries” (atherosclerosis), high blood pressure, coronary artery disease, and metabolic syndrome.
Flaxseed is also taken by mouth for acne, attention deficit-hyperactivity disorder (ADHD), kidney problems in people with a disease called systemic lupus erythematosus (SLE), liver disease, symptoms of menopause, breast pain, diabetes, prediabetes, obesity and weight loss, HIV/AIDS, depression, malaria, rheumatoid arthritis, sore throat, upper respiratory tract infections (URTI), and cough, bladder inflammation, enlarged prostate, osteoporosis, and to protect against breast cancer, endometrial cancer, lung cancer, colon cancer, and prostate cancer. It is also taken by mouth to prevent problems associated with hemodialysis treatment.
Flaxseed is sometimes applied to the skin for acne, burns, boils, eczema, psoriasis, and to soothe inflammation.
Flaxseed is used in the eye to help remove debris from the eye.