Report on Flax Seed Side Effects and Usage

Flax Seed

Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using Flax seed, also known as linseed (Linum usitatissimum). These are referred to as drug/herb interactions.

Warning 1 – All oral medications: Taking flax seed with any oral medication may decrease the body’s absorption of that medication.

Warning 2 – Laxatives: Using flax seed with laxatives may increase the effects of laxatives on the body.

Warning 3 – Water: The excessive consumption of flax seed without an increase in water intake can cause bowel obstruction.

Warning 4 – Diabetes: Flaxseed may lower the effects of some medications used in treating diabetes. There is also a concern that consuming flaxseed may cause the blood sugar level to drop too low.

Warning 5 – Gastrointestinal (GI) obstruction: The high fiber content in flaxseed may cause problems for those with a narrowed esophagus, inflamed intestine, or bowel obstruction.

Warning 6 – Bleeding disorders: The use of flaxseed may slow clotting time and increase the risk of bleeding in people with bleeding disorders.

Warning 7 – Pregnancy and breast-feeding: Because flaxseed can act like the hormone estrogen, there is a concern that this might harm a pregnancy. The effect on breast-fed infants when a mother uses flaxseed is currently unknown. Experts recommend you stay on the safe side and not use flaxseed if you are pregnant or breast-feeding.

Warning 8 – Triglycerides: Flaxseed that is partially defatted (lower alpha linolenic acid content) may increase triglyceride levels.

Warning 9 – Unripe Flaxseed: Do not eat unripe flaxseed as it is thought to be poisonous.

Used as a natural health remedy: Flax seed is used internally for following benefits:

  • Flax seeds contain high levels of dietary fiber, micronutrients, antioxidants, and omega-3 fatty acids.
  • Flax seeds may lower cholesterol levels, especially in women.
  • Studies suggest that flax seeds may benefit individuals with certain types of breast and prostate cancers.
  • Flax may lessen the severity of diabetes by stabilizing blood-sugar levels. *See warning number 4 above.
  • Flax seeds cools the hot flashes of menopause. (See other herbs for menopause)

Side Effects of Flax seed

The known side effects that may occur with Flax seed include:

  1. heartburn
  2. indigestion
  3. gas
  4. nausea

Other side effects may also occur when using Flax seed. (See form below)

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

Flax seed and Flax supplements are available over-the-counter.

Return to the Herb List.

For questions and answers about the side effects of herbs see the Herb Forum

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