Intended uses: To lower cholesterol; relieve constipation; decrease hot flashes; fight cancer.
What the science says: Mixed findings on whether flaxseed lowers cholesterol and relieves hot flashes. No reliable studies have found it effective for other uses.
Special precautions: May lower the body’s ability to absorb drugs taken by mouth. Don’t use flaxseed if you have a bleeding disorder. Can raise blood sugar.
Common side effects: Flaxseed should be taken with plenty of water; otherwise, it could worsen constipation or, in rare cases, even cause intestinal blockage. Can cause diarrhea.
Possible interactions: All medications taken by mouth, particularly blood thinners and antihypertensives.