By Melanie McGrice, Advanced Accredited Practising Dietitian, looks at the latest research on key dietary interventions to reduce allergy rates in children.
Australia has one of the highest rates of food allergies for both children and adults in the world. According to the 2011 Murdoch Children’s Research Institute’s ‘Health Nuts’  study – one of the most comprehensive research studies on childhood food allergies conducted in Australia – more than 10% of one-year-olds had a proven food allergy, and rates are on the increase.
Current research  has found that dietary changes in the lead-up to conception, during pregnancy and while breastfeeding have a significant impact on the likelihood of an infant developing food allergies. Some of the key dietary interventions found to reduce allergy rates include:
- Including allergens during pregnancy and breastfeeding. Many women still mistakenly believe that they should avoid allergens during pregnancy to reduce the risk of infant food allergies. However, current research suggests that including allergens (such as nuts, seafood and dairy products) frequently throughout pregnancy and breastfeeding helps to strengthen the baby’s immune tolerance.
- Adequate omega-3 intake. Long-chain omega-3 fats found in oily fish have anti-inflammatory properties, which may lower the risk of allergic disease in infants. For example, a randomised controlled trial  looking at how fish oil supplementation during pregnancy modifies immune responses found that infants in the fish oil group were three times less likely to have a positive skin prick test to egg at age one. To help your clients know which fish are safe to eat during pregnancy, click here.
- Optimum vitamin D intake. Low levels of vitamin D have been associated with a higher prevalence of allergic disease. For example, an Australia cohort study  involving infants with a parental history of allergic disease found that reduced fetal exposure to vitamin D increases the risk of eczema in infants by 12 months of age.
- Folic acid supplementation. Folic acid is important before conception and in the first trimester to minimise risk of foetal defects and aid development of the central nervous system. However, continued supplementation with folic acid into the later stage of pregnancy doesn’t reduce that risk, and there’s growing evidence  that this may increase the risk of allergies in offspring.
- Optimised gut flora. A healthy balance of gut flora is essential for the development of a healthy immune system. Prebiotics such as onions, asparagus and bananas are great for keeping good gut bacteria thriving. Furthermore, research suggests that probiotic supplements may also be beneficial.
- Breastfeeding for as long as possible. A systematic review  looking at correlation between breastfeeding and asthma strongly suggests that breastfeeding is protective against the development of childhood asthma. The review found that the longer infants were breastfed, the reduced risk of the onset of asthma and wheezing. The strongest association was found in children 0-2 years of age.
- Education for mums on the timing for introducing solids. Current infant feeding guidelines  recommend introducing solids at 6 months of age; however, there is emerging evidence that introducing solids after 4 months and before 6 months whilst breastfeeding is beneficial in reducing the risk of some allergies. Research  has also found that from 4 months of age, there is a window where immunological gut tolerance starts to develop. Although most current recommendations state that it is important to ensure the introduction of solids does not occur before 4 months of age, the perfect time to introduce solids needs to be researched further.
To help reduce the risk of allergies and optimise early life nutrition, consider referring your patients to a prenatal dietitian, or encourage them to download a pregnancy meal plan from www.melaniemcgrice.com/pregnancy.
About: Melanie McGrice is a fertility and prenatal dietitian. She runs online programs on prenatal nutrition for mothers-to-be, the ‘Nourish with Melanie’ YouTube channel and Nutrition Plus Fertility and Prenatal Dietetics Clinics, and is a member of Dietitian Connection. For more information see www.melaniemcgrice.com.
This article was originally published on RACGP and has been adapted for dietitians