Flaxseed is rich in fiber and omega-3 fatty acids, an essential nutrient especially important during the development of your child. However, flaxseed also contains lignans, chemicals that can mimic the actions of estrogen in your body. Normal levels of flaxseed in the diet are thought to be safe during pregnancy, but avoid taking supplements containing flaxseed lignans or eating abnormally large amounts of flaxseed.
Flaxseed is the richest source of lignans. As phytoestrogens, lignans may change the way the hormone estrogen works in your body. As precise hormonal control is necessary for development, this could be detrimental to your child. However, the effect that lignans have on estrogen is complex: Lignans mitigate the effects of estrogen levels being too high or too low. When estrogen levels are normal, as they are during your child's development, lignans likely have little effect.
Safety During Pregnancy
According to the Linus Pauling Institute, dietary intake of foods containing lignans has shown no adverse effects, and therefore is thought to be safe, even during pregnancy and breastfeeding. Additionally, the Linus Pauling Institute cites research showing that only one third of people of Western ancestry convert lignans into highly estrogenic forms. However, your health is unique: Consult with your doctor for prenatal dietary recommendations.
In addition to lignans, flaxseed is also a rich source of fiber, protein and the omega-3 fatty acid alpha-linoleic acid, ALA. Fiber can help maintain regular bowel movements that can be disrupted during pregnancy. Protein and omega-3 fatty acids are critical nutrients for your child. As an expectant mother, your dietary requirement for these increases beyond normal levels.
Flaxseed nutrients are better absorbed when ground into meal. Flaxseed meal can be added to baked goods, cereal and protein shakes and used as a thickener in soups. Though there is no recommended upper limit for flaxseed intake during pregnancy, consume in moderation. Limit your daily intake to no more than a few tablespoons.