Fatty acids in food are divided into two main groups: saturated fatty acids (where carbon atoms are connected by single bonds) and unsaturated fatty acids (where carbon atoms are connected by at least one double bond). Omega-3 fatty acids belong to the unsaturated group, with the first double bond located at the third carbon atom. This group includes DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid), which are found in fish, DPA (docosapentaenoic acid), which is present in some animal-based foods such as eggs, chicken, and beef, and ALA (alpha-linolenic acid), which is found in various vegetable oils.
Thus, DHA is an unsaturated fatty acid that belongs to the omega-3 group. It is considered an “essential” fatty acid because the body cannot produce it in sufficient quantities, so it must be obtained from external food sources. DHA is crucial for the nervous system, brain, and vision. Particularly for pregnant women, DHA plays a vital role during pregnancy, benefiting both the expectant mother and the fetus.
The Role of DHA:
As a key and essential component in the formation of brain and visual cells, DHA plays a special role in enhancing children’s intelligence and vision. For brain cells, DHA is a primary component of the fatty acids that make up the brain, essential for the myelination of nerve cells, and it influences the synaptic membrane—the part responsible for the release and reception of neurotransmitters—thereby enhancing the efficiency of signal transmission between brain cells. For visual cells, DHA is a crucial component in the formation of retinal cells and is the main element in the cells that receive visual images.
For expectant mothers and fetuses, DHA deficiency can lead to several potential risks:
In pregnant women: Research indicates that a lack of DHA may increase the risk of pregnancy complications such as preeclampsia, preterm birth, intrauterine growth restriction, and postpartum depression.
In fetuses and newborns: Insufficient DHA intake can affect an infant’s vision, particularly in preterm infants. Clinical trials have shown that DHA supplementation can benefit visual development and may reduce the risk of retinopathy in preterm infants. Regarding brain development, DHA accumulates in the fetal central nervous system before birth and plays a crucial role in the early stages of brain development in infants. A study involving infants under 18 months old found that those with DHA deficiency were at a higher risk of impaired language development, including delays in comprehension, understanding, and expression.
How Should DHA Be Supplemented for the Health of Both Mother and Baby?
The fetus and placenta rarely synthesize DHA on their own, making the DHA absorbed from the mother and the placenta’s transport function crucial for the fetus’s DHA intake. However, the typical diet of most pregnant women is largely deficient in DHA and cannot meet the current recommendations for DHA requirements without daily supplementation from external food sources.
For the Health of Both Mother and Baby, DHA Should Be Supplemented Through Natural Foods as a Priority
DHA supplementation through natural foods is crucial and should be prioritized for the health of both mother and baby. Common DHA-rich foods include:
- Seafood (mussels, shrimp, crab, squid, oysters) and fish: These are the primary dietary sources of DHA, especially fatty fish that live in cold waters, such as salmon, herring, tuna, mackerel, anchovies, sardines, and sturgeon roe. These fatty fish are the richest dietary sources of DHA, with each 75 g serving providing 750-1500 mg of EPA+DHA.
- Breast milk: It also contains natural DHA, and the DHA concentration in breast milk increases with the mother’s intake of EPA+DHA.
- Egg yolks
- Nuts: walnuts, almonds, peanuts
Additionally, DHA supplementation through nutritional products or supplements should be considered, taking into account factors such as: food preparation methods (DHA is an unsaturated fatty acid that easily oxidizes, especially when frying); the fishy smell of seafood and fish (particularly important for pregnant women experiencing severe morning sickness or those who dislike the taste of seafood and fish); and difficulties in feeding children, etc.
DHA Requirements for Pregnant Women
The International Society for the Study of Fatty Acids and Lipids (ISSFAL) recommends that pregnant or breastfeeding women consume at least 200 mg of DHA per day.
Specialist level 2 doctor. Nguyen Chi Thanh
References:
- National Guidelines on Nutrition for Pregnant Women and Breastfeeding Mothers (Decision No. 776/QĐ-BYT dated March 8, 2017, Ministry of Health).
- Ho Huynh Quang Tri (2010), “Omega-3 Fatty Acids and Cardiovascular Disease,” Ho Chi Minh City Cardiology Journal, online publication dated April 26, 2010.
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- Sibylle Kranz et al. Food Sources of EPA and DHA in the Diets of American Children, NHANES 2003-2010, Sibylle Kranz, et al., BAOJ Nutrition 2015.
- Poh Yee Choo et al. Cooking methods affect total fatty acid composition and retention of DHA and EPA in selected fish fillets. ScienceAsia 44(2):92. January 201844(2):92. DOI:10.2306/scienceasia1513-1874.2018.44.092.
- Enteral long-chain polyunsaturated fatty acids (LCPUFA) for preterm and term infants – UpToDate. Accessed: July 14, 2024.
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- https://www.issfal.org/assets/globalrecommendationssummary19nov2014landscape_-3-.pdf
