Flaxseed may be effective in helping in improving kidney function in those with lupus; reducing cholesterol, blood pressure and blood sugar levels; relieving constipation; relieving breast pain; and promoting a healthy weight.
The use of flaxseed and flaxseed oil for other conditions lacks reliable evidence.
Flaxseed products seem to be well tolerated and few side effects have been reported. Flaxseed should be taken with plenty of water as it contains fiber; otherwise, it can worsen constipation or, in rare cases, even cause intestinal blockage. Both flaxseed and flaxseed oil can cause bloating, diarrhea, and upset stomach.
Flaxseed and flaxseed oil may interact with:
- antibiotics
- anticoagulants (e.g., apixaban, warfarin)
- blood pressure lowering medications (e.g., amlodipine, ramipril)
- diabetes medications (e.g., metformin, sitagliptin)
- estrogens
- ezetimibe
Flaxseed and flaxseed oil should not be taken by those who:
- are experiencing a sudden change in bowel patterns that have lasted more than 2 weeks
- are experiencing rectal bleeding
- are unable to produce a bowel movement after using a laxative
- have a hormone sensitive cancer or condition (e.g., breast cancer, endometriosis, fibroids)
- have diabetes
- have symptoms of more serious conditions (e.g., abdominal pain, nausea, vomiting, or fever)
- have trouble swallowing
Stop taking flaxseed or flaxseed oil immediately and contact your doctor if you experience chest pain, vomiting, or difficulty swallowing or breathing.
Flaxseed oil may increase the risk of bleeds. Stop taking flaxseed oil at least 2 weeks before surgery.
Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.