Dr. Summit Shah
Leading allergy organizations around the world – including the American Academy of Allergy, Asthma, and Immunology, the European Academy of Allergy and Clinical Immunology, and the Canadian Society of Allergy and Clinical Immunology - have recommended that IgG tests not be used in the diagnosis of food allergies, intolerances, or sensitivities. Nonetheless, companies continue to push their food IgG tests on unsuspecting patients. At best, these tests are a waste of time and money. At worst, they result in misinformed patients who lack an understanding of their body’s reactions to certain foods and how best to manage potentially problematic reactions.
What is wrong with using the IgG test to identify adverse reactions to foods? Unfortunately, there is no scientific evidence that strongly suggests that IgG is predictive of one’s reaction to foods. According to expert allergists and immunologists, high IgG levels likely reflect a perfectly normal immune response to food, and a particularly high IgG level may indicate that someone has a good tolerance for the food in question. Nonetheless, someone administering a food IgG test who found high levels of IgG in response to the consumption of a certain food would tell the patient that the food had caused an adverse reaction.
Another significant problem with clinics using the IgG test to help patients make decisions about their diets is that these clinics often use the concepts of food allergies and food sensitivities interchangeably, though food allergies and food sensitivities represent vastly different bodily responses to food. A food allergy poses a potentially life-threatening situation wherein the immune system reacts to what could potentially be a very small portion of the food allergen. A food sensitivity, on the other hand, tends to refer to a reaction in the gastrointestinal (GI) system that is dose dependent, meaning that the more of the substance one consumes, the more affected they are.
In practical terms, when someone has a food allergy, they tend to have to avoid that food altogether. With food sensitivities, there is often no reason to avoid the food, but the patient may want to reduce the amount of that food they consume so that it does not cause them discomfort. Whereas a food allergy may lead to tongue swelling and difficulty breathing, a food sensitivity is more likely to cause bloating, stomach pain, and diarrhea.
Given that food allergies are much more serious than food sensitivities and should be dealt with in a more urgent manner, people who are concerned that they may adversely react to certain foods but are unsure if they have an allergy or sensitivity should consult a licensed allergist or immunologist so that they can be properly screened for allergies. These physicians can help to navigate symptoms and food reactions and determine the best course of action to ensure patients’ safety and comfort.
Allergies are on the rise in the United States, but a new study published in JAMA Network Open reveals that the reported increase in food allergies may be overblown. According to their data, the researchers who published the study concluded that almost 50% of people who believe they have a food allergy do not qualify for a food allergy diagnosis.
To determine the validity of people’s beliefs about their food allergy status, the scientists surveyed over 40,000 adults in the U.S. Nearly one in five of those surveyed believed that they had a food allergy. However, once details of their history and symptoms were evaluated, it was discovered that only about one in ten of those people truly suffer from a food allergy.
Allergy and immunology experts have pondered why this discrepancy exists and have posed two ideas. One idea is that those who falsely believe that they have a food allergy suffer instead from another type of allergy, such as seasonal allergies and do not recognize the true cause for their allergy symptoms. Another idea is that these people mistake food intolerance for food allergies. While food intolerance can make people feel unwell, an important distinction between food intolerance and food allergy is that only a food allergy engages the immune system.
What this means in a practical sense is that those with a food intolerance can still eat the food to which they are intolerant. Indeed, food intolerance works in a dose-dependent way, so small amounts of the food may be well-tolerated and larger amounts may lead to symptoms. Allergic reactions to food, on the other hand, can be life threatening even at incredibly small doses.
The researchers found that the symptoms reported by many of those who incorrectly believed they had food allergies were more consistent with seasonal allergies and food intolerance, corroborating experts’ suspicions that seasonal allergies and food intolerance could account for at least some cases where people erroneously believe they have a food allergy. Perpetuating the confusion about the distinctions between food allergy and food intolerance may be the rise in clinics that claim that they can identify adverse reactions with a single test – despite the inability of these tests to do so - and that use the concepts of food allergy and food insensitivity interchangeably. Educating patients on what food allergies are and how they can identify the symptoms of food allergies may help to improve people’s understanding of these allergies and how to manage them.
A new study published in Thorax suggests that a couple’s fertility may impact the likelihood that their children develop asthma. Previous research had shown that children who are conceived with the help of fertility treatments, known as assisted reproductive technologies (ARTs), may be at heightened risk for asthma. However, existing data have made it hard to determine if fertility treatments themselves lead to increased asthma risk, if the culprit could instead be whatever factor led to the couple’s reduced fertility, or if some other factor or combination of factors was to blame.
To help clarify the relationship between fertility and asthma risk in offspring, a research group leveraged data from national Norwegian health registries that included information on nearly 475,000 children who were born between 1998 and 2009. Included in these data were information on the use of fertility treatments, the time to conception, details of previous miscarriages, and maternal factors such as age, asthma status, weight, and smoking habits.
The researchers’ results corroborated previous findings that children conceived with the aid of ARTs are at a higher risk for developing asthma. Indeed, the researchers found that those conceived through fertility treatments were 42 percent more likely to develop childhood asthma – defined as the use of asthma medications during the previous year when children were seven – than those conceived in the absence of fertility treatments.
However, asthma risk also correlated with other factors indicative of fertility. For instance, children of those who took more than a year to conceive were more likely to develop asthma, as were those whose mothers had previously suffered first trimester miscarriages. The risk amongst children of mothers who had miscarried increased with the number of miscarriages. While the risk for asthma was seven percent higher in children whose mothers had experienced one miscarriage than in those who had experienced no miscarriages, the risk increased 24 percent for those whose mothers had had three or more miscarriages.
The increased risk amongst children of mothers with three or more miscarriages was comparable to the increased risk observed in those whose parents took over a year to conceive. The increased risk in the latter group was 22 percent. While these data point to a relationship between fertility and asthma in offspring, the increased risk of asthma observed in children who were conceived with the help of fertility treatments was much higher. These children experienced a heightened asthma risk of 42 percent
Parental fertility appears to play a role in children’s asthma risk, but something about fertility treatments or those who undergo those treatments may contribute more significantly to this risk than does low fertility itself. According to experts, ART procedures—including the modification of the hormonal environment—may affect fetal development and may account for some of the increased risk for asthma that is observed in children conceived through these methods. Future research will help to clarify the specific link between parental fertility and children’s asthma risk and hopefully provide insights into how we can intervene to reduce asthma risk in these children.
The pharmaceutical company Sanofi, in collaboration with Sema4—a predictive health company that spun out of Mount Sinai Health System—just launched a major study to help improve our understanding of asthma, as well as our ability to provide better treatments and recommendations to those who suffer from asthma.
This new longitudinal study, which will take place over five years and involve nearly 1,200 asthma patients, is unique in that it is employing cutting-edge digital and analytical methods to gain enormous amounts of data related to asthma in real-time and to produce valuable, actionable insights from these data.
Using assets like connected inhalers, sensor data from mobile devices, and environmental, genomic, and immunological information, the researchers will track and analyze how asthma affects individuals – and how it affects certain people differently than it affects others. They will also track what triggers asthma attacks, the mechanisms by which asthma occurs, and which patients are most likely to respond to specific therapeutic interventions.
Given that approximately 235 million people suffer from asthma across the globe and that roughly 400,000 people die each year as a result of the disease, there are significant opportunities to gather information about the disease, make sense of that information, and then use it to improve the global state of asthma and asthma care.
With the help of sophisticated machine learning techniques, Sanofi and Sema4 will not only be able to collect huge amounts of data on asthma and asthma patients, but they will also be able to process those data efficiently and translate the data into meaningful information that should allow clinicians and researchers to make better predictions about the course of asthma in individual patients
This information should also improve clinical decision making related to providing patients with the best therapeutic options that are currently available to them. In addition, this new information is likely to help the research community identify new drug targets to improve and expand the tools we currently have to address asthma and improve quality of life for those with the condition.
In recent years, oral immunotherapy has been used more and more to fight food allergies. This strategy works by desensitizing people to the substance to which they are allergic by introducing increasingly larger amounts of the substance. When successful, oral immunotherapy helps the immune system learn that the substance is not harmful, and as a result, the immune system stops overreacting to the innocuous allergen.
A new study on oral immunotherapy has given hope to those with wheat allergies and their families. The study, which was published a few weeks ago in the Journal of Allergy and Clinical Immunology, provided oral immunotherapy or a placebo to 46 people with severe wheat allergies. The participants ranged in age from 4 years old to 22 years old, and their wheat allergies were diagnosed through skin prick challenges.
The oral immunotherapy that was provided to half of the group was a low-dose vital wheat gluten that contained 70 percent wheat protein. Over the course of an entire year, the dose of vital wheat gluten given to those receiving the oral immunotherapy was slightly increased every two weeks.
After 52 weeks of participation in the study, 0 percent of those who were given placebo could tolerate a test dose of 4,443 milligrams of wheat protein, which is approximately the amount of wheat protein found in a hamburger bun or about a half a cup of cooked pasta. By comparison, more than half of those who had received oral immunotherapy were able to tolerate this dose with no adverse reactions.
Compared to the results of oral immunotherapy with other allergens like peanuts or milk, the response rates with wheat oral immunotherapy were a bit lower. According to experts, there could be a number of reasons for this discrepancy. For instance, the amount of protein found in wheat is lower than what is found in peanuts or milk, which can make studying wheat allergy more challenging. It is also possible that a higher dose of oral immunotherapy is needed to generate a larger response in those with wheat allergies.
Given that the results of this study come from a relatively small sample and a sample of only young people with severe wheat allergies, more research is needed to help clarify exactly how oral immunotherapy can be used to help those with wheat allergies. These new results, however, are promising in terms of the potential for oral immunotherapy to provide protection against this type of allergy.
The U.S. Food and Drug Administration (FDA) currently requires that companies include on their food labels the inclusion of eight common food allergens, including: peanuts, wheat, eggs, milk, shellfish, tree nuts and soybeans. Sesame may soon be added to this list
In 2014, a group that included the Center for Science in the Public Interest (CPI) petitioned the FDA to begin including sesame on the list of major allergens as evidence began to mount suggesting that more than 300,000 Americans suffer from sesame allergies and that only 100 milligrams of sesame can cause allergic reactions that can range from mild to the most severe forms that involve life-threatening anaphylaxis.
This move by CPI and others was consistent with others’ views on sesame allergies, as the European Union, Canada, Australia and New Zealand all already require companies to disclose when sesame is contained within its products.
A recent study published in Pediatrics suggests that 150,000 children in the United States are affected by sesame allergies, making it the ninth most common food allergen. More than half of those allergic to sesame carry EpiPens to protect themselves from severe allergic reactions.
Now, as the FDA considers adding sesame to the list of allergens that must be disclosed on food labels, it is also requesting information on the allergy through the end of the year, particularly from epidemiologists, allergy researchers, physicians, and nutritionists. The hope is that insights from these experts will help the FDA to deepen its understanding of sesame allergies and the threats they pose
A major goal for including sesame on the FDA’s list of major allergens would be to make it easier for consumers to identify sesame and avoid it when necessary. In addition to including major allergens on labels, companies are also required to use common names that are easily recognizable to consumers.
Currently, sesame may go unidentified because consumers are not familiar with the names that manufacturers use to describe the substance. Some other terms for sesame are: sim sim, sesamol, til, gingelly, and benne. Those with sesame allergies – and the rest of the allergy community – are anxiously awaiting the FDA’s decision on how to best handle the risks associated with sesame allergies.
The medical community has long recognized that obesity increases the risk of developing asthma. However, new research is complicating the story, suggesting that the opposite may also be true – i.e., that asthma may also increase the risk of becoming obese. According to the new data presented at the European Respiratory Society International Congress, people who have non-allergic asthma and those who have developed asthma as adults are at the highest risk of becoming obese.
The study, led by Dr. Subhabrata Moitra, included 8,618 people from 12 countries. Recruitment for the study started in the 1990s, and followed participants over 20 years. At the start of the study, these individuals were not obese, meaning that their body mass index, or BMI, was less than 30 kg/m2. Their asthma and BMI was then assessed at 10-year intervals over two decades. Participants were deemed to have asthma if they were taking asthma medication or if they reported having asthma and had had an asthma attack or had been awoken with shortness of breath at some point during the previous year.
Researchers evaluated the correlation between having asthma when the study began and the likelihood of obesity both 10 and 20 years later. They also considered other risk factors for obesity, including age, sex and physical activity. The scientists’ most significant finding was that 10.2 percent of people who had asthma at the start of the study had become obese ten years later, compared to only 7.7 percent of those who did not have asthma. Thus, though all people tended to gain weight and be more likely to become obese as they aged, the risks for obesity were higher among those with asthma than among those without asthma.
The specific link between asthma and obesity is unclear, but there does seem to be a relationship that makes having one of these conditions increase people’s likelihood of developing the other. Future research will aim to clarify the impact of each disease on the other so that we can develop strategies for reducing the risk of obesity in those with asthma and vice versa.
Over the last decade, a major mystery in the rise of red meat allergies has been partially solved, as scientists have discovered that being bitten by the Lone Star tick – which tends to be found in the southeastern United States – increases the risk of developing allergies to red meat. By increasing sensitivity to alpha-gal, which is a type of sugar molecule, ticks can make their victims become allergic to red meat that contains this type of sugar.
New evidence has now emerged that chigger bites may also lead to red meat allergies by lowering people’s tolerance to alpha-gal. The findings have been published in The Journal of Allergy and Clinical Immunology: In Practice.
The clue that chiggers may be helping to spread red meat allergies emerged from case reports from the University of Virginia and Wake Forest Baptist that described patients who had recently developed an allergy to red meat had not been exposed to ticks, but had recently experienced chigger bites. Researchers at UVA found that of 301 red meat allergy patients surveyed, 5.5 percent had experienced chigger bites over the previous decade but had not had any exposure to ticks.
To confirm whether chiggers are truly spreading red meat allergies, scientists will begin investigating whether chiggers have traces of alpha-gal in their saliva.
Chiggers are tiny red larvae that come from arachnid mites in the Trombiculidae family. These larvae eventually evolve into arachnids with eight legs. Being only about 1/150th of an inch in size, they are not easy to identify with the eye. However, once someone has been bitten by chiggers, they tend to experience intense itching. The subsequent scratching undertaken to relieve itching can lead to secondary infections.
While the itching they cause may lead people to assume that chiggers are similar to mosquitoes, they are actually more closely related to ticks. Like the Lone Star tick, chiggers can be found in the southeastern part of the United States, but they are more widespread than the Lone Star tick – also prevalent in the Midwest and found in northern states, through New York.
Red meat allergies can range from mild symptoms including hives to life-threatening reactions that involve anaphylaxis. Unlike many allergies that occur immediately after exposure to the allergen, the alpha-gal allergy often involves a delayed reaction that occurs between three and 12 hours after exposure.
There is no cure for this allergy, and the only way to prevent it is to avoid mammalian meat products. Future research into the specific causes of red meat allergy may help in the development of an effective treatment for this allergy.
The short answer is yes. The British Association of Dermatologists have recently reported on what they call an “allergy epidemic” resulting from exposure to a methacrylate – a chemical that is commonly used in gel polish, gel nails and acrylic nails. A major challenge with this rising allergen is that those experiencing allergic reactions do not always realize that their reaction results from a chemical on their nails because the symptoms can occur all over the body.
What happens when the allergy occurs is that the methacrylate comes into contact with the skin before it is dried or hardened by a UV light. Once this exposure occurs, nails may loosen, but severe red and itchy rashes can also occur, and these can pop up anywhere on the body. The rashes are commonly found on the eyelids, face, neck and genitals. Respiratory difficulties can even occur in the most severe cases.
It is important that people who are allergic to methacrylate identify the cause of their allergies so that they can avoid the allergen in the future. Unfortunately, gel polish and gel and acrylic nails are not the only places where methacrylate is found. They are used in acrylic plastic production and are found in devices, orthopedic cement and dressings used in surgeries and dental treatments.
According go the British Association of Dermatologists, approximately 2.4 percent of people tested are allergic to at least one type of methacrylate, and those who apply gel or acrylic nails or gel polish at home or who work in the beauty industry are at enhanced risk for methacrylate allergies. Recognizing that you are at risk for methacrylate allergies can help you identify the trigger if you do experience an allergic reaction.
A study recently published in the Annals of the American Thoracic Society has shown that four out of every 10 women with asthma may eventually develop chronic obstructive pulmonary disease (COPD). The research team, led by Teresa To, studied 4,051 women who were diagnosed with asthma. They followed the women on average for 14 years and found that 1,701 of them – or 42 percent – developed COPD.
The researchers also studied asthma and COPD overlap syndrome, which is often referred to as ACOS. They found that there has been a sharp rise in women with ACOS in recent years, and that more women than men die from ACOS. They also found that fine particulate matter, which is a common air pollutant that has been shown to travel to the lungs and cause lung disturbances, is not as much of a factor in the development of ACOS as other individual risk factors, such as smoking.
According to their analyses, women who had smoked a pack each day for at least five years developed ACOS at significantly higher rates than those who smoked fewer or no cigarettes. Nonetheless, refraining from smoking does not guarantee that women with asthma will avoid ACOS. In fact, 28 percent of those who developed ACOS had never been smokers. Other factors that are associated with higher rates of ACOS development are: obesity, lower levels of education, unemployment and rural residence.
Based on the factors that appeared to increase the risk for developing ACOS, the scientists suggested that low socioeconomic status and lower access to care or lower adherence to medication recommendations could account for the increased incidence of ACOS. Indeed, improperly treated asthma can result in more frequent asthma attacks and more opportunity for remodeling conducive to COPD to occur within the lungs.
The good news is that the factors that were identified as associated with ACOS development are modifiable, which suggests that the rising incidence of ACOS among women could be curbed with proper interventions. Given that women who developed end up in the hospital more frequently and have a poorer quality of life than those who are diagnosed with only asthma or only COPD, it is important that we figure out ways to minimize ACOS. More research aimed at how to prevent the development of ACOS will help clinicians to provide care and recommendations for their patients to reduce the likelihood that asthma will develop into COPD.