Essential fatty acids (EFAs) are lipids that the human body cannot synthesise and therefore must be consumed in the diet to meet metabolic demands.
There are two families of EFAs: omega-3 fatty acids (commonly sourced from fish) and omega-6 fatty acids (commonly sourced from vegetable oils).
Omega-3 and omega-6 fatty acids are constituents of the membranes of all cells in the body. Much research has been done highlighting the importance of maintaining a healthy omega-3 to omega-6 ratio in preventing or treating numerous health conditions such as cardiovascular disease, inflammatory conditions and eye diseases.
When it comes to conception, pregnancy and breast-feeding, omega-3 fatty acids are vitally important for mum, dad and the baby.
Fertility
A recent study found that plasma eicosapentaenoic acid (EPA) and red blood cell docosahexaenoic acid (DHA), two important omega-3 fatty acids, were reduced in infertile women.
Fertile men have been found to have higher blood and sperm levels of omega-3 fatty acids when compared to infertile men. A strong negative correlation has been found between low omega-3 levels and total sperm count, sperm motility, and sperm morphology.
Pregnancy
The metabolic demand for DHA increases in pregnancy, particularly in the last trimester when foetal brain and nervous system development is at its greatest.
The benefits of supplementing with omega-3 fatty acids during pregnancy have been evaluated in a number of randomised controlled clinical trials. Recent meta-analyses of these studies showed that supplementation with fish oil in the second half of the pregnancy resulted in an increase in the length of gestation and also reduced the risk of women giving birth before 34 weeks. Birth weight was also slightly greater in infants whose mothers supplemented with fish oil.
Increased intake of maternal DHA in pregnancy has been shown to increase foetal supply and lead to higher DHA concentrations in cord blood. A higher DHA supply to the foetus during pregnancy and after birth was associated with beneficial effects to visual acuity, cognitive function and maturity of sleep patterns.
Breast-feeding
Because growth of the baby, and in particular the baby’s brain, occurs rapidly in the first year of life, it is essential that high quality nutrition be supplied to the infant to ensure that all nutrient needs are met.
The DHA content of breast milk depends on the maternal diet. Lactating women who supplement with DHA have been shown to have a marked increase in milk DHA.
DHA in the infant is important for visual acuity and research shows that human milk DHA levels were positively correlated to visual development in breast-fed infants.
Other benefits of omega-3 fatty acid supplementation in the breast-feeding mother may include improved language production, comprehension and improved cognitive function, however further research is needed in these areas.
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Other references available on request