An estimated 4%–6% of children in the United States suffer from life-threatening food allergies (NHANES, 2006). The eight most common food allergens are milk, eggs, peanuts, soy, wheat, tree nuts, fish, and shellfish. Although most children do “outgrow” their allergies, reactions to peanuts and shellfish can be lifelong (Johns Hopkins, 2018). Until recently, it has been common practice to avoid exposing young children to the common offending foods until they were older. For years, pediatricians advised avoiding peanuts until age three (The Guardian, 2017), but new research has lead to revised health guidelines. The new guidelines come out of several studies conducted in recent years that challenged the advice to ban peanuts in infancy, a standard practice in the United Kingdom, Australia and the United States (The New York Times, 2017). The hope is to prevent food allergies before they start by exposing a child at a young age, some experts even suggest while still in utero. The Learning Early about Peanut Allergy (LEAP) study is on the frontlines of this new research after having studied peanut allergies among Jewish children. This study caught my eye due to its use of Bamba, a puffed corn snack similar to puff Cheetos, but peanut flavored. Being part Jewish, my nieces and nephews have enjoyed this snack for years.
The brain, gut, immune system connection has long been an interest of mine, especially with adult onset eczema. I’m also curious about the topic due to knowing many mothers with children who have food allergies. These leave the entire family on edge and fearful of ingesting offending foods. I was curious to see what the current research recommends regarding allergen exposure.
2. Next, address the scholarly research you uncovered. Discuss the questions the authors were trying to answer. Briefly describe the design of the research (number of people in the study, ages, gender, use of a placebo control, length of study, etc.) Discuss the key results. You will do this for each of the three articles separately.
Scholarly Study #1: Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy, published in The New England Journal of Medicine in 2015.
Researchers were concerned by a rapidly growing trend of childhood peanut allergies and wanted to evaluate the current guidelines for consumption and avoidance to determine if the strategies were effective. They noticed that Jewish children raised in the United Kingdom had a higher incidence of peanut allergies than of those raised in Israel. They came to find out that Jewish children in Israel are exposed to peanuts much earlier than children typically are in the U.K. Leading them to hypothesize that the early introduction of peanuts to the diet may offer protection from the development of peanut allergy. The Learning Early about Peanut Allergy (LEAP) trial was conceived to determine whether the early exposure to peanut would be and strategy for the prevention of peanut allergy.
The trial was randomized, open-labeled, approved by an IRB board, and overseen by an allergy safety board. The peanut product used in the study was an Israeli snack called Bamba. Smooth peanut butter was provided to those that didn’t like Bamba. Participants had to be between the ages of 4 and 11 months old. The researchers assigned 640 infants with severe eczema, egg allergy, or both, to consume or avoid peanuts until 60 months of age. The participants were divided between the two groups based upon results of a skin-prick test for peanut allergy. The infants were clinically evaluated at the ages of 12, 30 and 60 months of age. Serum levels of peanut-specific IgE, IgG, and IgG4 antibodies were measured at each visit. Telephone consultations were conducted weekly until participants reached 12 months of age, every 2 weeks from 12 months to 30 months of age, and monthly thereafter. The study had a 98.4% retention rate; 10 participants were withdrawn voluntarily by a parent or guardian or were lost to follow-up.
The outcome was measured via an oral food challenge. Those in whom peanut allergy was unlikely (no wheal after a skin-prick test at months 30 and 60, no history of allergic symptoms after ingestion of peanut, and no history of anaphylaxis in response to any food) received 5 g of peanut protein in a single dose. A double-blind, placebo-controlled food challenge was conducted for other participants (with a total of 9.4 g of peanut protein administered in increments) (Du Toit, et al, 2015). The study concluded that early and regular consumption of peanut products led to a decrease of peanut allergies in high-risk infants. It also showed that avoiding peanuts led to an increase of peanut allergy. The findings contradict the guidelines that encourage peanut avoidance as a strategy to prevent allergy.
Scholarly Study #2: Peanut, Milk, and Wheat Intake During Pregnancy is Associated with Reduced Allergy and Asthma in Children, published in the Journal of Allergy and Clinical Immunology in 2014.
Researchers were concerned about the rapidly growing trend of childhood allergies and asthma and wanted to determine what role intrauterine exposures through maternal diet had in the development of both. The American Academy of Pediatrics previously advised that “no maternal dietary restrictions during pregnancy are necessary with the possible exception of excluding peanuts.” Subsequent systematic reviews of the literature concluded that the current evidence is inadequate to support any dietary restrictions during pregnancy (Bunyavan ich, et al., 2014). The study focused on maternal intake during early pregnancy of the common eight foods that trigger allergies including peanuts, milk, wheat, eggs, and soy. The Project Viva prebirth cohort participants were pregnant with single babies, and screened via in-person interviews and food frequency questionnaires at 10 weeks gestation and again at 26-28 weeks gestation. After the babies were born, child-focused interviews and questionnaires were administered at 6 months, 1 year, and annually after that until age 7. Of the 2128 children delivered in Project Viva, 1277 mother-child pairs were included who sat for an in-person interview at mid-childhood.
Of the 1277 children who presented for an in-person interview at mid-childhood, 699 agreed to have blood drawn and 616 (87.7% of those with blood samples) children had sufficient sample to measure allergen-specific IgE. Sensitization to a food allergen was considered positive if the respective allergen sIgE level was 0.35 kU/L or more. A child was considered to have a food allergy to peanut, milk, wheat, egg, and/or soy if he or she had an sIgE level of 0.35 kU/L or more to the particular food. Additionally, a child was considered to have had an allergic reaction if his or her mother answered yes to the question, “Has your child ever had an allergic reaction to peanuts?” and yes to at least one of the following categories of allergic reaction symptoms with peanut ingestion: hives, wheezing, dizziness, vomiting and diarrhea, or anaphylaxis (Bunyavan ich, et al., 2014).
The outcome showed that maternal consumption of allergenic foods during early pregnancy were related to lower incidence of allergy and asthma in mid-childhood. Maternal peanut intake during the first trimester was associated with a 47% reduction in the odds of childhood peanut allergic reaction; maternal milk intake during the first trimester was associated with reduced odds of childhood asthma and allergic rhinitis, and maternal intake of wheat during the second trimester was associated with reduced childhood atopic dermatitis. No direct associations between maternal egg or soy intakes and childhood outcomes were observed. The strongest association was from first trimester administration when the fetal immune system is developing. The study findings do not support the previous guidelines for avoiding certain foods during pregnancy to prevent allergy and asthma in children. Consuming these foods could actually be helpful.
Scholarly Study #3: Timing of Food Introduction and Development of Food Sensitization in a Prospective Birth Cohort, published in Pediatric Allergy and Immunology in 2017.
Researchers started to question the efficacy of the guidelines for delaying childhood exposure to common allergenic foods. In conjunction with The Canadian Healthy Infant Longitudinal Development (CHILD) study they support their findings.
3495 pregnant women recruited from the general population in Toronto, Manitoba, Edmonton, and Vancouver. 2124 children included in this analysis all had skin testing between 9 and 18 months of age, skin prick test data for both mothers and fathers, and sufficient data to determine the timing of introduction of cow’s milk products, egg, and peanut.
3. Critically evaluate your sources (scholarly journal articles and internet sources too), and comment on their authenticity, validity, and reliability.
The New York Times was established in 1851 and has had a long-standing reputation of accuracy in reporting. The Guardian is a British newspaper, founded in Manchester, England in 1821. It also has a long-standing reputation of accuracy and has historically been praised for its investigative journalism. WebMD is commonly joked about on the street, especially when using the symptom checker. It should never be used to in lieu of a medical diagnosis by your physician, however, it is fact checked by a group of physicians and allied medical professionals with the intent to provide medical and health information in layman’s terms. The two most important distinctions it has from a scholarly source are that it is not funded by an institution, nor does it conduct its own research as an organization. The New England Journal of Medicine is a weekly medical journal published by the Massachusetts Medical Society. It is one of the most prestigious and longest running peer-reviewed medical journals. The Journal of Allergy and Clinical Immunology is a monthly peer-reviewed medical journal reporting research on allergy and immunology. It is one of two official journals of the American Academy of Allergy, Asthma, and Immunology. Pediatric Allergy and Immunology is a peer-reviewed medical journal on pediatric immunology and allergies. It was established in 1990 and is published eight times a year by John Wiley & Sons, which is a global publishing company that specializes in academic publishing.
4. Identify cause and effect relationships that you found in your scholarly research and also your Internet website exploration. Did you find any arguments that seemed to be false? Explain.
Articles for the lay public are often times written with a catchy, click bait type of headline. Especially in today’s polarized media. Every attempt should be made to validate the claims made in an article and to dig deeper into any subject of interest. For this project, I avoided looking at overtly flashy websites, but the articles for the lay public are definitely supported by ads on the sidebars. While scrolling through them I didn’t specifically see any products that were conflicts of interest.
Study #1 states that “No manufacturer of peanut products contributed to the design of the study, the accrual or analysis of the data, or the preparation of the manuscript. The peanut snack used in the study, called Bamba, was purchased from Osem at a discounted rate.” (Du Toit, et al., 2015). Study #1 and #3 were both funded by the National Institute of Health in the U.S. and Canada, respectively. All three studies acknowledged the limitations of their research. General limitations of longitudinal studies include incomplete follow up, increased financial demands, a large pool of participants is needed, increased risk of human error or bias.
5. Visit the two websites listed below, and feel free to explore other websites related to the scientific method. Explain how the scholarly research studies that you found on your topic, are related to the scientific method. Did the researchers utilize elements of the scientific method to generate new knowledge? Explain. http://www.sciencemadesimple.com/scientific_method.html
All three of the studies used multiple elements of the scientific method. Each started out with a question regarding the efficacy of the previously stated guidelines, or about the mechanism of allergen exposure. They hypothesized that early exposure to allergenic foods would decrease the incidence of food allergies later in life. They laid out their method of research, gathered a population of individuals to observe, and then administered the protocol, either by exposure to the food in question or by avoiding it. They kept detailed records so that the study could be replicated; they then analyzed their results and discussed their findings.
6. Give a final analysis of your topic and tell the reader what logical conclusions you reached after researching this topic.
I think early exposure and sensitization while the immune system is developing makes a lot of sense. Not only do I think it is a good idea physically, but also psychologically. I’ve witnessed friends fall off the deep-end of worry and transfer that maternal stress to their children. Their children, in turn, become scared of school and parties (side note: I do not in any way fault my friends for following “outdated” professional recommendations). We as a society love to run with any information given to us, rather than pursue moderation.