Allergy, Infant and Children | March 8, 2016 | Author: The Super Pharmacist
It is estimated that food allergies affect 5 in every 100 young children, with reported food allergies rising significantly in the last 20 years due to changing diets and patterns of consumption.
Food allergy symptoms will typically appear somewhere between a few minutes and an hour after eating a particular food that causes a reaction. If children are being exposed to new foods and parents are worried about allergies, there are a number of signs that they can look out for.
The most common symptoms include:
In the most severe circumstances, some allergic reactions can result in difficulty breathing and, very rarely, a loss of consciousness.
Until recently, recommendations from a wide range of paediatric bodies stated that parents should wait until their child was over 12 months before introducing whole milk, over 24 months before being introduced to eggs, and over the age of 3 before being exposed to peanuts, tree nuts and various types of fish. Rather than being based on specific evidence conducted under trial conditions, much of the guidance was based on expert opinion. The emergence of a growing body of new evidence has resulted in this precautionary advice coming under a renewed level of scrutiny.
A systematic review of globally available literature, recently conducted by the Food Standards Agency (FSA) in the United Kingdom, revealed a number of key findings that have informed new guidelines for paediatricians in regards to advice on exposure to potential allergens. The review, covering 7 trials deemed of a high enough quality to be included, found that there is no conclusive evidence that maternal dietary intake of nuts or peanuts whilst pregnant has any impact on the development of food sensitisation or future food allergies in children.
The review also revealed that there is no conclusive evidence to suggest that the avoidance or delayed introduction of particular allergens provides additional protection from the development of allergies, or reduces the likelihood of allergens developing in the future.
In practice, a large number of paediatricians still recommend waiting until babies are a little older before being introduced to the 8 allergenic foods – milk, eggs, peanuts, tree nuts (such as walnuts or almonds), soy, shellfish, fish and wheat.
Although the evidence suggests that there is no additional risk of an allergy developing if children are exposed to such foods earlier -
the rationale many health professionals use in regards to waiting slightly longer is that allergic reactions may be easier to manage in older babies and less distressing than a severe reaction in a younger baby.
Recommendations around the use of whole cow's milk remain roughly the same: risks from allergic reactions aside, it is not considered suitable because both breast milk and formula have a higher nutritional content. The introduction of yoghurts and soft cheeses are also considered safe as the proteins that are present in these dairy products are broken down and less likely to cause distress or discomfort in the form of stomach trouble.
The evidence around the introduction of honey remains roughly the same as previous expert opinion, with many experts recommending that it is not given to children before the age of 2 due to the possibility of causing a potentially serious disease called infant botulism (a potentially life threatening disease in which bacteria growing in the gastrointestinal tract causes the production of significant levels of toxins). Similarly, many health experts continue to advise that children should not eat nuts or peanuts until they are 4-5 years old because, as well as the allergy threat, there is also an associated choking risk.
In general, a number of studies show that infants who are given cow's milk or soy protein formula have a higher incidence of atopic dermatitis and wheezing illness in early childhood, supporting a widely high held expert view that breastfeeding should be encouraged as a result of its protective factor against certain allergens.
Pregnant women had previously been advised to avoid peanuts or foods containing traces of peanuts in order to reduce the risk of their children develop allergies at a later date, but this was unsubstantiated by evidence. Developments in the evidence base have resulted in these restrictions being removed. Breast milk remains the substance least likely to trigger an allergic reaction, and it is also easy to digest and strengthens the immune system.
Some studies have speculated that breastfeeding may also reduce early eczema, wheezing and cow’s milk allergy, but the evidence for this assertion remains inconclusive. For infants at risk of allergy where the mother is unable to breast feed, hydrolyzed infant formulas are the preferred hypoallergenic substitutes over cow’s milk and soy formulas.
In addition to this, there are a number of other non-medical actions that can be taken to try and reduce the risk of allergies such as reducing contact with dust mites and ensuring children are not exposed to tobacco smoke at an early age.
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