Flaxseed and flaxseed oil are rich sources of an omega-3 fatty acid called alpha-linolenic acid. Research shows that omega-3 fatty acids are good for the heart.
Flaxseed has a lot of fiber. It's also high in substances called lignans that are found in plants. Lignans contain phytoestrogens. Some research suggests that phytoestrogens may help fight cancer. Flaxseed oil does not have fiber or phytoestrogens.
Flaxseed can be used whole or crushed. It also comes in a powder form as meal or flour. It's often mixed with or baked into foods. Flaxseed oil is available as a liquid or as capsules.
People use flaxseed and flaxseed oil to help lower cholesterol and blood sugar and to treat digestive conditions. Some people also take flaxseed to treat inflammatory diseases.
What the research says
Here's what the research shows about flaxseed and flaxseed oil for the following conditions:
- Heart disease. Some studies suggest that alpha-linolenic acid, which is found in flaxseed and flaxseed oil, might benefit people with heart disease. Some research also suggests that flaxseed and flaxseed oil might help lower high blood pressure, which may help lower the risk of heart disease.
- Cholesterol levels. Several studies have found that taking flaxseed daily can lower total cholesterol and low-density lipoprotein cholesterol, also called LDL cholesterol. LDL is considered the "bad" cholesterol.
- Diabetes. Flaxseed might lower blood sugar in people with type 2 diabetes, but studies are mixed. Flaxseed oil has not been found to help lower blood sugar.
- Cancer. The research is mixed on whether flaxseed or flaxseed oil has an effect on cancer.
- Menopausal symptoms. Research results are mixed when it comes to the use of flaxseed to treat symptoms of menopause, including hot flashes.
- Constipation. Some studies have shown flaxseed to be helpful in easing constipation.
