Infants and young children need a lot of energy to grow and develop, yet they have small tummies and so cannot eat much at one time. That is why they need to eat more often than older children and adults, and why they need an energy dense source of food.
Fat fulfils this criteria, providing more than double the energy of carbohydrate. Hence, breast milk is fat-rich with approximately 45% of the energy coming from fat.
Fat is not just used as an energy source however. There are different types of fats with different roles. The main ‘families’ of fat are saturated fats, monounsaturated fats and polyunsaturated fats. The polyunsaturated fats can be further divided into the omega-6 fats and the omega-3 fats.
It is the omega-3 fats that have received much attention in nutrition research. If you are taking a fish oil supplement, it is this group of fats that are present. We know these fats are important for adult health, but they also play a vital role in the development of infants and young children, particularly for the brain and eyes.
There are different omega-3 fats, with the parent being alpha-linolenic acid (ALA). Humans cannot make ALA and therefore this is an essential fat that we must consume in the diet. ALA is found in plant foods such as walnuts, linseed, chia seeds, legumes and in some vegetables including broccoli and leafy greens.
There are important long chain omega-3 fats that also have key roles, chiefly docosahexaenoic acid (DHA). Humans can make DHA from ALA, but have a limited capacity to do so. In order to get the right amounts of these fats, they must also be consumed in the diet. The richest source is seafood, especially oily fish, with smaller amounts present in meat and eggs.
DHA is especially important for infants. High concentrations of this fat are found in the retina of the eye and in the brain, where levels continue to increase for the first two years of life. The amount of DHA found in breast milk varies according to how much the mother consumes in her diet. The Australian recommended intake for long chain omega-3s is therefore increased during pregnancy (from 90 mg per day to 115 mg per day).
Formula milks are scientifically designed to best replicate breast milk and most will include long chain omega-3s, particularly DHA. Our Australia recommendations only specify a total omega-3 fat intake of 0.5 g per day for infants up to the age of 1 year (but do not specify DHA per se), but from ages 1-3 years, a long chain omega-3 intake of 40 mg a day is specified.
To ensure your child is getting enough long chain omega-3s, be sure to eat enough yourself if breastfeeding or choose a formula that includes them, particularly DHA.