IMPORTANCE OF OMEGA-3 ESSENTIAL FATTY ACIDS IN PREGNANCY
by Dr. Silloo Patel M.D. (Hom.)
Summary:
The article sheds light on the importance of Omega-3 essential fatty acids in pregnancy. The article also highlights the dietary foods rich in Omega-3 fatty acids and their daily requirement during pregnancy.
Key words:
Omega-3, Omega-6, Pregnancy, Development, Diet
Kindergarten and pre-school are vital steps in a child’s growth, aiding in the journey toward becoming fully cognisant and independent adults. However, the first big jumpstart begins in utero, long before a baby’s first ABCs are taught. Recent studies have shown that Omega-3 fats are critical for the complete development of the human brain, and is especially needed for foetal neural development during pregnancy and, later, during the first two years of life. But unlike many other substances that our body requires for the maintenance of optimum health, we cannot synthesise these essential fats, making Omega-3 an important part of our diet, whether eaten or taken in the form of supplements.
Here’s what you need to know about this essential nutrient:
‘Omega’ refers to where the first double bond appears on the fatty acid chain of unsaturated fatty acids. Of the twenty or so edible fatty acids, only Omega-3 and Omega-6 cannot be synthesised by the body. This means all of the Omega-3 and Omega-6 fatty acids, so vital for a foetus’ proper growth, must be supplied by the mother-to-be through placental transfer.
A typical modern diet is filled with Omega-6 fatty acids, particularly linoleic acid (LA) which is readily converted to its biologically active form Arachidonic acid (AA). Omega-6 fatty acids can be found in vegetable oils like corn oil, sunflower oil, safflower oil, cottonseed oil, etc. These are extensively used in processed and fried foods. One teaspoon of corn oil can satisfy the daily Omega-6 requirement, but most individuals eat 10 to 20 times that amount.
In contrast, the intake of Omega-3 fatty acids is suboptimal. The richest dietary sources of Omega-3 fatty acids are fish and fish oil supplements. Plant-based Omega-3 fatty acids, found as precursor α-linolenic acid (ALA) in nuts and seeds like walnuts, almonds and flax seed and oil: flaxseed oil ( 57%). Canola oil (11%), and soybean oil (8%) are also available, but are poorly converted to the biologically active Omega-3 fatty acids, EPA (Eicosapentaenoic acid) and DHA (Docosahexaenoic acid). The range of conversion of ALA to EPA is generally between 0.2% and 9%, so trying to obtain all Omega-3 fatty acids from plant-based oils requires ingestion of too many fat calories.
Unfortunately, most people do not consume Omega-3-rich foods on a regular basis. The ratio of dietary Omega-6 to Omega-3 fatty acids in the modern diet approximates 10 : 1, or even as high as 25 : 1. The recommended ratio is closer to 2-4 of Omega-6 to 1 of Omega-3.
The Omega-3 fatty acid EPA and the Omega-6 fatty acid AA are essential structural components of every cell in the body. Both EPA and AA serve as precursors for biologically active compounds called eicosanoids.
Specific to pregnancy, a high ratio of AA to EPA that comes from a diet rich in Omega-6, can lead to the formation of potent 2-series prostaglandins, PG E2 and PGF2α. These are known to be associated with the initiation of labor, preterm labour in particular. It can also lead to the formation of the vasoconstrictor thromboxane A2, associated with preeclampsia.
On the other hand, Omega-3 fatty acid eicosapentaenoic acid (EPA) is a precursor for the 3-series of PGs and produces PGE3 and PGI3, which promote relaxation of myometrium. EPA and DHA competitively displace AA in the membrane phospholipids and thereby reduce production of 2-series eicosanoids. Further, EPA may also play an important role in the transport of DHA across the placenta and its intracellular absorption. This is why a diet that provides a closer balance of Omega-3 to Omega-6 fatty acids may be very important to pregnant women.
Foods with Lowest Omega-6 to Omega-3 Ratios
Dietary ω-3 decreases tissue concentrations of AA, so there is less to form ω-6 eicosanoids.
In the early 1980s, a Danish study began to look into Omega-3 fats and their derivative, DHA (Docosahexaenoic acid). The women living on the Faroe Islands were found to deliver more full-term babies, who also had higher birth weight than in 31 other countries. This was followed by studies on pregnant women supplemented with DHA and EPA at different times in the gestation period. As we now know, positive results were found in the groups taking Omega-3 fats. Finally, and most importantly, when the scientists evaluated the same group of infants four years later, it was found that the children with higher mental processing scores were born to mothers supplemented with fish oil, rich in EPA and DHA.
A later trial in Australia yielded similar results in infant cognition when conducting a similar trial. At twenty weeks of gestation until delivery, 98 women were randomised to receive either fish oil or olive oil. At birth, infants from mothers in the fish oil-supplemented group had higher DHA and EPA levels and lower AA levels in the cord blood, when compared with children born to mothers in the olive oil-supplemented group. When evaluated at 2.5 years of age, children in the fish oil-supplemented group had higher scores for hand and eye coordination in comparison to those in the olive oil group. In this study, as in others, eye and hand coordination scores and other tests of mental acuity correlated with Omega-3 levels (EPA and DHA) in cord blood erythrocytes, and inversely correlated with Omega-6 levels (AA).
Here’s another reason expecting mothers shouldn’t neglect their Omega-3 supplements. Pregnancy-related and postpartum depressions have been shown to affect infants’ cognitive development and behaviour. Research has demonstrated that an increased intake of long-chain polyunsaturated fatty acids during pregnancy reduces the risk of depressive symptoms in the postpartum period. This is because Omega-3 fatty acids are transferred from the mother to the foetus during pregnancy, thereby decreasing maternal stores. Polyunsaturated fatty acids have also been shown to decrease pro-inflammatory cytokine production, which is elevated in depressed patients. Because many women are reluctant to take antidepressant medication while they are pregnant or breastfeeding, it is possible that an increased intake of Omega-3 fatty acids (through the mother’s diet and supplements) could prove beneficial and protective to both mother and child.
Just as the name suggests, the essential fatty acid Omega-3 is vital to a child’s development. If a mother (and through her, her infant) are deficient in it, the child’s nervous and immune system may never fully develop. The parts of the brain that Omega-3 affects is the learning ability centre; emotional areas controlling anxiety and depression; and auditory and visual perception. Omega-3 fats also aid in balancing the autoimmune system, and can help reduce the ever-growing number of children with allergies, colic, and skin problems. Considering its impact on all these areas, an Omega-3-deficient diet can lead to a lifetime of unexplained emotional, learning, and immune system disorders.
Now more than ever we are seeing a rise in cases of emotional, learning, and immune system disorders in our population. It appears clear that a widespread nutritional deficiency is causing a breakdown in people’s health. It is enough to make one wonder whether the prevalence of infant and childhood illnesses like sinus allergies, chronic ear-nose-throat infections, as well as emotional and psychological disorders like hyperactivity, autism, and learning disabilities also has their basis in nutrition, particularly in the lack of Omega-3 fatty acids.
How to Meet Omega-3 Fatty Acids Needs During Pregnancy
(Choose vegetable oils that are rich in the Omega-3 fatty acid linolenic acid and low in the Omega-6 fatty acid, linoleic acid, so reduce intake of vegetable oils rich in Omega-6 fatty acids e.g., sunflower oil, corn oil, cottonseed oil)
To meet daily needs for 650 mg of Om-3, of which 300 is DHA you need to eat;
[1] 1.4 g of Omega-3 fatty acids from vegetable oils can get from:
1/2 tsp flaxseed oil,
1 tbsp canola oil, or
1 tbsp + 1 tsp soybean oil
[2] And by consuming 2 servings of low-mercury (< 0.05 (µ/g [ppb]) seafood per week.
Total milligrams of Omega-3 fatty acids in 1 6-oz serving
(mg of DHA in parentheses). Each entry below has <0.05 ppb of mercury
Shrimp 880 mg (320 mg)
Salmon 620 mg (260 mg)
Pollock 520 mg (360 mg)
Catfish 340 mg (180 mg)
Scallops 740 mg (360 mg)
Sardines 2.2 g (1.2 g)
Light tuna 380 mg (170 mg)
Based on consuming 2 fish servings a week, the average intake per day is 100-250 mg Om-3 fatty acids and 50–100 mg DHA.
[3] Remainder of the 650 mg EPA and DHA
Use fish oil capsules containing EPA and DHA
Require 400–550 mg Omega-3 fatty acids, with 225 mg as DHA each day
Use 1 or 2 capsules/day to meet these needs
[Few vegetarian sources of Omega-3 are also commercially available namely algae-derived DHA]
About the Author
Dr. (Mrs.) Silloo D. Patel M.D. (Hom.), S.N.H.S.(Adv.nutrition)UK
Dr. Silloo D. Patel has taught Physiology at Smt. C. M. P. Homeopathic Medical College, Irla, Mumbai, since 1985.
Currently she is a Guest Professor in the Dept. of Physiology at the Smt. C. M. P. Homeopathic Medical College and studying M.Sc. in Dietetics and Food Service Management.
