Omega-3 Fish Oil and Pregnancy

Why is Omega-3 Fish Oil Important During Pregnancy?

Adequate intake of Omega-3 fats is essential to maintaining the balanced production of the hormone-like substances called prostaglandins. Prostaglandins help regulate many important physiological functions including blood pressure, blood clotting, nerve transmission, the inflammatory and allergic responses, the functions of the kidneys and gastrointestinal tract and the production of other hormones.

Depending on the type of fatty acids in the diet, certain types of prostaglandins may be produced in large quantities, while others may not be produced at all. This prostaglandin imbalance can lead to disease. The role of omega-3s in producing beneficial prostaglandins may explain why they have been shown to have so many health benefits, including the prevention of heart disease, improving cognitive function and the regulation of inflammation.

High doses of omega-3s have been used to treat and prevent mood disorders, and new studies are identifying their potential benefits for a wide range of conditions including cancer, inflammatory bowel disease and other autoimmune diseases such as lupus and rheumatoid arthritis.

Scientific research is constantly expanding our knowledge of nutritional needs in pregnancy. Among the most recent developments in this field is the importance of Omega-3 Fatty Acids in both the development of a healthy baby and in the health of the mother.

Omega-3 Fish Oil Benefits & Dosage

Omega-3s are a family of long-chain polyunsaturated fatty acids that are essential nutrients for health and development. Unfortunately, these are not synthesized by the human body and therefore must be obtained from diet or supplementation.

However, the typical American diet is greatly lacking in Omega-3’s. Research indicates that the two most beneficial omega-3s are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Although EPA and DHA naturally occur together and work together in the body, studies show that each fatty acid has unique benefits.

EPA supports the heart, immune system, and inflammatory response. DHA supports the brain, eyes, and central nervous system, which is why it is uniquely important for pregnant and lactating women.

The Benefits of Omega-3 Fish Oil

Omega-3s have been found to be essential for both neurological and early visual development of the baby. However, the standard western diet is severely deficient in these critical nutrients. This omega-3 dietary deficiency is compounded by the fact that pregnant women become depleted in omega-3s because the fetus uses omega-3s for its nervous system development.

Omega-3s are also used after birth to make breast milk. With each subsequent pregnancy, mothers are further depleted. Research has confirmed that adding EPA and DHA to the diet of pregnant women has a positive effect on visual and cognitive development of the baby. Studies have also shown that higher consumption of omega-3s may reduce the risk of allergies in infants.

Omega-3 fatty acids have positive effects on the pregnancy itself. Increased intake of EPA and DHA has been shown to prevent pre-term labor and delivery, lower the risk of preeclampsia, and may increase birth weight. Omega-3 deficiency also increases the mother’s risk of depression. This may explain why postpartum mood disorders may become worse and begin earlier with subsequent pregnancies.

Which Foods Contain Omega-3 Fish Oil?

The best sources of EPA and DHA are cold-water fish such as salmon, tuna, sardines, anchovies, and herring. Many people are justifiably concerned about mercury and other toxins in fish, especially during pregnancy. For this reason, purified fish oil supplements are often the safest source of EPA and DHA. A high-quality fish oil supplement from a reputable manufacturer like Nordic Naturals delivers the health benefits of EPA and DHA without the risk of toxicity.

Many people think that flaxseed or flaxseed oil contains omega-3s. But flaxseed contains the shorter-chain omega-3, ALA (alpha-linolenic acid), which is different from the longer-chain EPA and DHA. EPA and DHA are the Omega-3s that the body needs for optimal health and development. While it was once thought that the human body could convert ALA to EPA and DHA, current research shows that such conversion rarely and inefficiently occurs. Fish oil is a more reliable source of EPA and DHA.

Safety Considerations

Quality fish oil is safe to take during pregnancy. Fresh fish can often contain environmental toxins like mercury that accumulate during its life span. These toxins can be virtually eliminated during the manufacture and processing of fish oil, with the use of high-quality raw materials and an advanced refining process.

Some brands of fish oil are of higher quality than others. A reputable fish oil manufacturer should be able to provide documentation of third-party lab results that show the purity levels of their fish oil, down to the particles per trillion level.

Fish Oil Recommendations

  • Investigate the manufacturing process–How is the fish oil manufactured and what are the quality standards that the manufacturer is using? The quality standards that exist for fish oil-including the Norwegian Medicinal Standard, the European Pharmacopoeia Standard and the voluntary U.S. standard established by the Council for Responsible Nutrition’s 2006 monograph-guarantee quality by setting maximum allowances for toxins.
  • Smell–Does the fish oil smell fishy? Research shows that fish oils only smell unpleasant when the oil has started to degrade and is becoming rancid. A high-quality fish oil supplement will not smell fishy.
  • Taste– Does the fish oil taste fishy? The freshest and highest-quality fish oils should not taste fishy. Avoid fish oils that have really strong or artificial flavors added to them because they are most likely trying to hide the fishy flavor of rancid oil.

Dosage Recommendations

ISSFAL (the International Society for the Study of Fatty Acids and Lipids) has established the following recommended minimum dosage chart:

Infants (1-18 months):

0-15 lbs: 32 mg/lb EPA+DHA

Children (1.5-15 yrs):

15 mg/lb EPA+DHA

Adults (15-115 yrs):

500 mg EPA+DHA (with a minimum of 220 mg EPA and 220 mg DHA)

Pregnant and Lactating Women:

300 mg DHA daily

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Compiled using information from the following sources:

1. Measurement of organochlorines in commercial over-the-counter fish oil preparations: implications for dietary and therapeutic recommendations for omega-3 fatty acids and a review of the literature. Melanson SF, et al. Arch Pathol Lab Med 2005;129:74-77.

2. Measurement of mercury levels in concentrated over-the-counter fish oil preparations: is fish oil healthier than fish? Foran SE, et al. Arch Pathol Lab Med 2003;127:1603-1605.

3. International Society of the Study of Fatty Acids and Lipids (ISSFAL)

www.issfal.org