Do you need Omega 3 supplements during pregnancy?
Fish oil supplements that contain DHA (the omega-3 fatty acid docosahexaenoic acid) are marketed to pregnant women as a way to support their baby’s brain development and other benefits.
Where is this theory coming from?
- Brain weight at birth represents 27% of adult brain weight
- 60% of the adult brain weight is composed of lipids.
- Lipids, in particular fatty acids, are the main brain building blocks and essential for brain growth, brain maduration as well as maintenance.
Many interpreted these finding as showing benefits of eating fish during pregnancy for child brain development.
This is important for the unborn baby, who receives DHA from mum’s blood. DHA is transferred from the mother to the baby by the placenta. Large amounts of DHA go to the baby’s brain, particularly in the last trimester when the brain undergoes a rapid growth spurt. The supply of DHA during this important period of brain development is crucial.
Supplement manufacturershave used the finding to market benefits of fish oil, leading the general public to believe that DHA SUPPLEMENTS for pregnant women are beneficial for brain development.
Taking Omega-3 Supplements Doesn’t Make Smarter Kids.
There is NO conclusive evidence that demonstrates the effects on the foetus/infant of omega-3 SUPPLEMENTATION in pregnancy and lactation:
- There is currently NO evidence to support that n-3 LCPUFA (long chain polyunsaturated fatty acids) supplementation during pregnancy and/or lactation favourably affects child adiposity.
- Gestational supplementation with fish oil during the second or third trimester of pregnancy is NOT associated with reduced risks for gestational diabetes mellitus (GDM), pregnancy-induced hypertension (PIH), and pre-eclampsia (PE).
- Based on the available evidence, LCPUFA supplementation did not appear to improve children's neurodevelopment, visual acuity or growth. In child attention at five years of age, weak evidence was found (one study) favouring the supplementation. Currently, there is inconclusive evidence to support or refute the practice of giving LCPUFA supplementation to breastfeeding mothers in order to improve neurodevelopment or visual acuity.
- There is limited evidence to support maternal n-3 LCPUFA supplementation during pregnancy and/or lactation for reducing allergic disease in children. Few differences in childhood allergic disease were seen between women who were supplemented with n-3 LCPUFA and those who were not.
- Several trials of DHA-rich fish oil during pregnancy have found a slight increase in the length of pregnancy in women taking the supplement. This has led to small decreases in the number of children born very preterm in these studies. While further studies are needed to prove this effect, DHA is one of the only interventions that has been identified with the potential to prevent preterm birth.
A healthy, varied diet is the best way to ensure all nutrient requirements are met. There is general consensus fish should be part of a healthy diet during pregnancy; it is an excellent source of DHA and other omega-3 fatty acids, protein and a variety of vitamins and minerals.
Everyone should try to eat two portions of fish per week, one of which should be oily fish. In the UK there is no specific recommendation of a dose for omega-3 for the general population.
You can eat most types of fish when you're pregnant. Eating fish is good for your health and the development of your baby, but you should avoid some types of fish and limit the amount you eat of some others.
- Fish to avoid: shark, swordfish or marlin.
- Fish to restrict: You should also limit the amount of tuna you eat to: No more than 2 tuna steaks a week (about 140g cooked or 170g raw each), or 4 medium-sized cans of tuna a week (about 140g when drained)
This is because tuna contains more mercury than other types of fish. The amount of mercury we get from food isn't harmful for most people, but could affect your baby's developing nervous system if you take in high levels of mercury when you're pregnant.
When you're pregnant, you should also avoid having more than 2 portions of oily fish a week, such as salmon, trout, mackerel and herring, as it can contain pollutants like dioxins and polychlorinated biphenyls (PCBs).
Other Omega-3 sources
People who do not eat fish can get omega-3 from the following foods: nuts and seeds e.g. walnuts and pumpkin seeds; vegetable oils e.g. rapeseed and linseed; soya and soya products e.g. beans, milk and tofu; and green leafy vegetables.
Benefits of taking food rich in Omega-3
· May protect the heart and blood vessels from disease
· Supports healthy development of your baby during pregnancy and breastfeeding
· May be protective in maintaining good memory and prevention and treatment of depression
Intake of omega-6-rich oils found in sunflower, corn, and cottonseed oils should be minimized because they are converted to substrates that compete with EPA (the omega-3 fatty acid Eicosapentaenoic acid). Pregnant women should reduce their intake of these oils and substitute others that are rich in omega-3 fatty acids like flaxseed and soybean oil.