Eating for you and your baby: dietary advice for pregnancy

As soon as you found out you were pregnant, you probably started to read every book you could find to make sure you were doing what was best for your baby. Eating a healthy diet is at the top of the list. After all, you are what you eat and it's important to provide your baby with the best nutritional building blocks from the start.

There's one vital piece of nutritional advice you can act on as soon as your pregnancy test is positive and that's to eat a diet rich in omega-3 foods. Recent research has shown that your unborn baby will benefit, as omega-3 fats have an important role to play in the healthy development of your baby's brain, nerves and eyes.

DHA omega-3 is referred to as an essential polyunsaturated fatty acid (EFA) which means it is a nutrient that the body needs but can't produce in adequate levels by itself. Instead, we rely on our diet to make up the difference. Women of childbearing age who consume a typical Western diet are at risk of low stores of DHA. This is because the primary dietary sources of DHA are fatty fish and organ meats, dietary choices that are not staples of the Western diet. So why is DHA important? Well, it's vital for the healthy development of the membranes in the eye, brain and nervous system of your unborn baby. For this reason, adequate levels of DHA are particularly crucial during the explosive growth spurts within the second half of pregnancy. Babies can't produce their own DHA at this stage so they must rely on your dietary intake. The same need applies after birth. DHA naturally occurs in breast milk, but as a nursing mother you can make sure your milk is rich in DHA by eating a diet rich in DHA.

Studies have shown that infants who enjoy higher levels of DHA in the womb and through breast milk may enjoy a whole range of health benefits including: better hand-eye coordination, sharper vision and possibly a lower risk of heart disease in later life.1,2,3 Emerging studies also seem to show that DHA may help women carry to a healthy term, reducing the risk of near-term birth.4 DHA may also promote a mother's emotional wellbeing after pregnancy and may lower the risk of post-natal depression too.

While the evidence is substantial, nutritional advice for mothers is not always clear-cut. The best known source of DHA is oily fish: salmon, trout, tuna, sardines and pilchards. Along with an increased awareness of the nutritional value of these fish, there have been warnings about mercury levels in some oily fish. For this reason, the UK Food Standards Agency recommends that pregnant women limit their consumption of oily fish to only one portion per week, but does not extend these recommendations to other fish.

Walnuts and flaxseed oil are actually sources of another omega-3 fatty acid, alpha-linolenic acid, or ALA, which the human body can convert to DHA, though slowly and unpredictably.

A growing awareness of the dietary sources of DHA and the inclusion of DHA in certain fortified foods and supplements is making it easier for women to include this important nutrient in their diets every day. Look for DHA fortified eggs, milk, bread, cereals, yoghurt,  salad dressing and margarine in your supermarket.

For vegetarians or non-fish eaters, vegetarian supplements derived from micro-algae are a useful way of increasing DHA omega-3 intake. Certain microalgae are natural sources of DHA. While most people believe that fish produce their own DHA,  it’s the algae they eat that make them a rich source of DHA. Because it is from algae and not fish, there is no risk of ocean-borne pollutants which can potentially be found in fish and fish oils.

One of the most widely used vegetarian DHA supplements in the U.S. is life'sDHA™ from microalgae. life'sDHA™ can be found within supplements for pregnant and breastfeeding mothers in addition to a growing number of fortified foods, including eggs, soy milks, milk, juices, yoghurt and nutrition bars.

1 Horwood LJ, et al. Breastfeeding and later cognitive and academic outcomes. Pediatr, 1998. 101: e9
2 Jensen CL, et al., Effects of maternal docosahexaenoic acid intake on visual function and neurodevelopment in breastfed term infants. American Journal of Clinical Nutrition, 2005. 82(1):1579-86
3 Forsyth JS, et al. Long chain polyunsaturated fatty acid supplementation in infant formula and blood pressure in later childhood: follow-up of a randomised controlled trial. BMJ, 2003. 326(7396):953
4 Smuts CM, et al. A randomized trial of docosahexaenoic acid supplementation during the third trimester of pregnancy. Obstetrics and Gynecology, 2003. 101 (3): 469-479

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