A large body of evidence attests to the health benefits of eating fish, in particular oily fish, that contain high levels of long chain omega 3 (Ω-3) fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) that play an important role in reducing the risks of cardiovascular diseases. DHA is also an important structural component of the eye and the nervous system including the brain. This is used to make nerve and brain cells and also the parts of the eye which communicate sight (retina). The human body can not produce these essential fatty acids so it is very important to take these in through the diet. Therefore, an early supply through maternal diet and breastmilk is vital for optimal visual and neural development and function in the developing baby both in the mother’s womb and during infancy.
‘Aquamax’ has substantially progressed knowledge in this area by validating the health benefits of fish produced on the new diets in pregnant women and young children.
For these two groups, information on the health benefits of fish is far from complete, due mainly to difficulties in conducting nutritional trials during pregnancy because of the potential presence of environmental contaminants in fish. Such concerns have been linked mostly towild marine fish but also encompass farmed fish because of the use of marinefish meal (FM) and fish oil (FO) in aquaculture feeds.
Withinthe ‘Aquamax’ project, the development of tailor-made salmon, with minimal contaminant levels and a high content of Ω-3 fatty acids, has enabled the project to conduct the first nutritional intervention study on oily fish consumption in pregnancy.
Evidence has pointed to a low dietary intake of longchain Ω-3 fatty acids during pregnancy being a significant factor in infants developing atopic disorders (asthma, hay fever, dermatitis and allergies). Children who are affected by allergies have lower amounts of Ω-3 fatty acids in their blood and blood cells. This observation suggested that increasing the supply of Ω-3 fatty acids to babies,even before they are born, may help to “normalise” their levels of Ω-3 fatty acids and lessen their chances of developing allergies.
123 pregnant womenfrom families with a history of atopy participated in the study. Of these, 61 continued their habitual diet (characterised by low fish consumption) and 62 consumed two salmon meals per week from week 20 of pregnancy until delivery.
The goal was thus to investigate whether the consumption of farmed ‘Aquamax’ salmon would improvethe nutritional status of these women and that of their babies. Furthermore,follow up on the development of atopic disorders has been made on the babies.
Results show that when pregnant women (who do not regularly eat oily fish), eat two portions of salmon per week, the intake of long chain Ω-3 fatty acids (EPA and DHA) is significantly increased, as well as the levels of selenium and vitamin D which are also found in oily fish. Moreover, they have a higher amount of long chain Ω-3 fatty acids in their blood stream and so, therefore, will their baby. Since these key functional fatty acids decline in the mother’s blood during pregnancy, due to the demands of the growing baby, this is important. This dietary change can thus enable the mother to supply more optimally these nutrients to the developing baby before it is born. Consumption of salmon in pregnancy also resulted in a higher content of EPA and DHA in breast milk meaning allowing better supply of these fatty acids to the baby after birth.
The follow up on atopic disorders performed on the babies at birth and at 6 months of age did not point out any differences between the two study groups, the next check will be at 3 years of age and thiswill allow a more intensive comparison of allergic symptoms.
Further studies of increased long-chain Ω-3PUFA provision during pregnancy, lactation, and infancy are needed to moreclearly identify the immunologic and clinical effects in infants and children to identify protective and therapeutic effects and their persistence.
The intervention study has been supported by data from a parallel cross-sectional study in China assessing nutrient intakes among pregnant women from 3 different regions that representdifferent eating habits with respect to fish and seafood (coastal, inland,river and lake). This observational study aimed to investigate the impact of different dietary intakes of long chain Ω-3 PUFA on the nutrient status of pregnant women and their babies and markers of allergy and sensitisation ininfants. The women selected were encouraged to remain on their habitual diets during the course of the study. Dietary surveys were conducted on the women recruited and fatty acid analyses of their diets and their blood determined.These measurements will be associated with atopic disease outcomes in the babies.
