Introducing Common Allergenic Foods Early on Is Key to Prevention

<p>For decades, the standard line of advice from pediatricians to parents regarding food allergies was to hold off on introducing common triggers until the child was past their first year (if not longer) to avoid a bad reaction. Everything from fish to tree nuts was put on hold in families across the nation, but as well-intentioned as that move may have been, these parents were acting on bad advice.</p> <p>A few years back, breakthrough research turned our strategy on its head by demonstrating that there was generally no benefit in waiting to expose kids to these foods; the allergies showed up whether parents waited or not. </p> <p>In other words, we had put the cart before the horse.</p> <h2>What is an allergy?</h2> <p>Our immune systems work wonders for keeping us safe against invasive pathogens, but it doesn’t always know who the enemy is. In the case of allergies, it mistakenly sees a certain protein inside a food as being harmful, and once a person’s system has coded itself to watch out for that protein, an allergic reaction occurs every time they eat that food.</p> <p>Food allergies are different from an intolerance, as the latter does not affect the immune system (although some of the symptoms do cross over). The incidence rate of food allergies is around 7% for babies and young children (roughly 1 in 13). The most common examples include:</p> <ul> <li>Milk (and dairy products)</li> <li>Eggs</li> <li>Peanuts</li> <li>Tree nuts (e.g., almonds, cashews, walnuts)</li> <li>Soy</li> <li>Seafood</li> <li>Wheat</li> <li>Sesame</li> </ul> <p>Eggs, milk, and peanuts are the most common types of food allergies in kids, while peanuts, shellfish, fish, and tree nuts tend to be the most severe. Between 1997 and 2007 the prevalence of food allergies in kids hiked up by 18%. Even though a lot of kids grow out of their allergies, some are lifelong — especially the normally more severe ones listed above. </p> <figure><img alt="" src="https://cdn.storymd.com/optimized/7ogP4kFjdx/thumbnail.jpg" /> <figcaption>Ninety percent of all allergies are caused by these eight foods: milk, egg, peanut, tree nuts, wheat, soy, fish, and shellfish. <em> Source: U.S. Department of Agriculture</em></figcaption> </figure> <h2>How do I spot a reaction?</h2> <p>The severity of a reaction can vary greatly, and it can happen quickly after exposure to the allergen (think minutes or even seconds). Typical symptoms of a mild to moderate reaction include:</p> <ul> <li>Hives, swelling, or a rash</li> <li>Stuffy/runny nose with itchy, watery eyes</li> <li>Nausea and vomiting</li> <li>Cough</li> <li>Diarrhea (less common but may occur later in the day).</li> </ul> <p>When a reaction is severe, immediate medical attention is required. Look out for signs that the individual has gone into anaphylactic shock:</p> <ul> <li>Swelling in the mouth, tongue, or throat</li> <li>Hives that continue to spread</li> <li>Breathing difficulties, repeated coughing, and wheezing</li> <li>Poor ability to swallow</li> <li>Hoarse voice</li> <li>Pale/blue lips and/or face</li> <li>Fainting or weakness</li> </ul> <p>The National Institute of Allergy and Infectious Disease states that even a minuscule exposure to an allergen can trigger a severe reaction in highly sensitive sufferers — just 1/44,000 of a peanut kernel may be sufficient.</p> <h2>Where do food allergies come from?</h2> <p>We don’t know exactly. There are many theories out there about the cause (e.g., genetics, the dual-allergen exposure hypothesis, hygiene), and this has become more complicated now that the incidence rate is on the rise. While experts don’t have a definitive answer, it’s likely a combination of multiple factors.</p> <p>Children are not born allergic, but we do know that genetics make it more likely that a baby will develop an allergy at some point. If both parents have allergies, their kids have a 60%–80% risk of developing them too, compared to 5%–15% in kids without allergic parents.</p> <p>We don’t have evidence to show that problems in pregnancy cause food allergies to develop, so playing the blame game in relation to your diet while you were pregnant is unfair. The first weeks and months of life entail exposure to environmental allergens through the skin (not the gut), and your baby’s system will start developing antibodies in response. </p> <p>"The moment a 'foreign object' touches our skin, even on a microscopic level, those allergic pathways start to be embedded in the system, and we start to activate B cells and T cells that set down memory responses for life," explained Kari Nadeau, a professor of pediatric medicine, to the BBC. </p> <p>B cells and T cells both play important roles in our immune response because they help us to react to perceived threats and remember that reaction in future events so that we can respond quicker. A child could be inadvertently exposed to the likes of peanuts through dust or residue on mom or dad’s hands, and that can put the ball of an immune response in motion long before they’ve tried eating such food.</p> <p>By the time they get there, it may be too late.</p> <p>"If the body is first and repeatedly introduced to foods through the skin, as opposed to through the mouth and gastrointestinal tract, it may increase the likelihood of sensitization to that food, and possible allergy," said Jennifer Bufford, vice president of clinical operations at Food Allergy Research and Education.</p> <p>According to Nadeau, kids with eczema (a condition that causes skin to become cracked, dry, and itchy) are especially vulnerable to developing food allergies because their skin has microscopic holes that allow particles to enter the body more easily.</p> <figure><img alt="" src="https://cdn.storymd.com/optimized/Nq4BZaT7oK/thumbnail.jpg" /> <figcaption>Baby with Eczema. <em>Source: TheVisualMD</em></figcaption> </figure> <h2>Early exposure may have been the solution all along</h2> <p>As research continued into the best prevention practices, some key papers emerged.</p> <p>A 2015 paper on the #1 villain, peanuts, hammered the point home. Researchers in the UK noticed that Jewish children living in Britain were around 10 times more likely to have a peanut allergy than Jewish kids living in Israel. Since the two groups had the same ethnic background, it had to be something in their environment that made the difference, and that turned out to be the approach to their diet.</p> <p>The UK kids typically did not eat peanuty foods within their first year of life, whereas the Israeli children were raised from early on with a snack called Bamba, a type of corn puff made with peanut butter.</p> <p>This finding formed the basis of a follow-up study involving some 600 children, all of whom had eczema or an egg allergy (both increase the risk of developing a peanut allergy). The participants were split into two groups: a Bamba group, and another that was to stay away from all peanut-based products. This carried on until the children were five years of age.</p> <p>In the end, just 3% of the kids who consumed peanut products while growing up developed an allergy, as opposed to 17% of those who did not consume peanuts.</p> <p>The important window of early exposure was further highlighted in a randomized trial from 2016 involving 556 children. The team found that if you stop feeding them peanut products even though they had previously been given them as babies, they won’t go on to develop allergic reactions if they resume consumption. </p> <p>The take-home message was that early food exposure can have a lifelong impact on people.</p> <h2>Evolving guidelines</h2> <p>We all know how serious a severe allergic reaction can be, and understandably, guidelines on introducing peanuts and other allergens were initially slow and conservative. That’s no longer the case. </p> <p>"We now believe peanuts, which are not actually nuts but are legumes, should be given to babies as early as four months, when solids are first introduced," said Maria Garcia-Lloret, co-director of the UCLA food allergy clinic. </p> <p>"It should not be the very first food a parent gives; I suggest mixing a little bit of peanut butter in some oatmeal. However — and this is critical — babies with eczema and other established food allergies are considered high-risk. For those kids, introduction to peanuts should be carefully monitored under the guidance of a pediatrician."</p> <p>Breastfeeding exclusively for the first 4–6 months remains the ideal way to nourish your child. It’s the least likely food to trigger a reaction, they can digest it easily, and it boosts their immune system. Breastmilk may reduce the odds of early eczema, wheezing, and allergies to cow’s milk. For mothers unable to breastfeed, you can get special infant formulas that act as hypoallergenic substitutes.</p> <p>The American Academy of Allergy, Asthma, and Immunology recommends that you begin introducing single-ingredient infant foods in that 4–6-month window, e.g., fruits, veggies, and cereal grains. Introduce them one at a time and give each item a trial of 3–5 days to give yourself insight into whether a potential allergen is present. </p> <p>“Egg, dairy, peanut, tree nuts, fish, and shellfish can be gradually introduced during the same 4–6-month window after less allergenic foods have been tolerated,” stated the group. “In fact, delaying the introduction of these foods may increase your baby’s risk of developing allergies.”</p> <p>North of the border, Canadian authorities have followed suit. The Canadian Paediatric Society published updated guidelines in 2019 encouraging parents to offer non-choking versions of food items that contain common triggers like peanuts and eggs around six months of age (but not before four months). This can be effective in preventing allergies in high-risk kids. </p> <p>If your child already has severe eczema and/or a known egg allergy, make sure that you talk to your pediatrician about how to go about introducing other potentially allergenic products like peanuts. A more delicate approach is needed for safety reasons.</p> <figure><img alt="" src="https://cdn.storymd.com/optimized/JdPOW5ujo3/thumbnail.jpg" /> <figcaption>Small Changes, Big Trouble. <em>Source: TheVisualMD</em></figcaption> </figure> <h2>Safety caveats</h2> <p>If you already know about a food allergy in your kid or have good reason to suspect one, don’t give them the relevant food item. You may be wondering “how can I know?”, and the answer is that it’s not always possible. </p> <p>What you should do is look out for signs of a reaction: eczema, bloody stools, rashes, irritability, vomiting/nausea after eating. Talk to your doctor if any of these appear or if a parent or sibling has food allergies.</p> <p><strong>Never give babies or toddlers actual peanuts — they’re a choking hazard</strong>. Snacks designed for babies with peanuts being part of the ingredients are what is meant instead. </p> <h2>Introducing potentially allergenic foods</h2> <p>When offering common food allergens for the first time, there are some tips you can use to help things go smoothly:</p> <ul> <li><strong>Make sure the texture is safe</strong>. Around the six-month mark, you can introduce foods of a semi-solid composition (lumpy, minced, tender-cooked, or ground).</li> <li><strong>Blend</strong>. You can mix in small amounts of the target food into infant cereal or a fruit puree as part of your testing.</li> <li><strong>Sample</strong>. Failing that, you can try a direct sampling with a small amount (around a quarter of a baby spoonful).</li> <li><strong>Wait and watch</strong>. Give it 10–15 minutes before offering more and keep an eye out for any signs of a reaction. It’s okay to give them other foods during this wait.</li> </ul> <p> </p> <h2>More on Food Allergies</h2><ul><li><a href="https://soulivity.storymd.com/journal/nwlv3lyfem-food-allergy" target="_blank">Food Allergies: Causes, Diagnosis, Living With</a></li><li><a href="https://soulivity.storymd.com/journal/jkalg2qibm-living-with-food-allergy" target="_blank">Living with Food Allergy</a></li><li><a href="https://soulivity.storymd.com/journal/j6geak6fzw-cow-s-milk-allergy" target="_blank">Cow's Milk Allergy: Causes, Symptoms, Prevention</a></li></ul>