Higher consumption of pro-inflammatory compounds found in cooked meats, called advanced glycation end-products (AGEs), was linked to higher rates of wheezing in a national sample of more than 4,000 children, according to the study, which was published December 2020 in the journal Thorax. Wheezing is a common asthma symptom in children and adults. The study found that increased levels of AGEs were tied to more incidents of kids reporting wheezing that disrupted their sleep, limited their exercise, or even led to an emergency room visit. “Our study builds on prior work that suggests diet may play a role in airway health and asthma-related symptoms,” says the study’s senior author, Sonali Bose, MD, an assistant professor of pediatrics and pulmonary, critical care, and sleep medicine at the Icahn School of Medicine at Mount Sinai. A growing body of research suggests dietary patterns high in pro-inflammatory foods (including saturated fats and meat) are linked to respiratory disease. Dr. Bose and others say these observational findings are too preliminary to prompt changes to nutrition guidelines or for kids to change their eating patterns yet, but the data warrants further study. Asthma is the most common chronic condition among children, currently affecting an estimated 6.1 million kids younger than 18 years old, according to the American Lung Association (ALA). It’s a chronic lung disease that makes it harder to move air into and out of the lungs. Kids and adults can be diagnosed at any age — and while treatment can help manage asthma, it cannot be cured. “As we and others accumulate further evidence, we may discover that avoiding foods that are pro-inflammatory may be a modifiable way to reduce asthma-related symptoms during childhood,” she says. RELATED: What Causes Asthma and Asthma Flare-Ups?

Researchers Look at Survey Data on Eating Habits and Wheezing

For their study, Bose’s team examined health data for 4,388 children between ages 2 and 17 taken from the National Health and Nutrition Examination Survey (NHANES). The group included children who had been diagnosed with asthma as well as kids who had not. The Centers for Disease Control and Prevention (CDC) NHANES survey evaluates the health and nutritional status of adults and kids through interviews and physical exams. The NHANES survey included a 139-item food frequency questionnaire that recorded kids’ reported intake of red meat, poultry, processed meats, and seafood, along with reported respiratory symptoms. The researchers estimated AGE consumption scores on the basis of the kids’ overall meat intake. Even after controlling for age, gender, and asthma diagnosis, they found higher AGE intake was significantly associated with wheezing, as well as with wheezing that required medication. The data also revealed that those with the highest AGE intakes had increased rates of wheezing before bedtime and wheezing during exercise. Children who consumed diets highest in AGEs were 18 percent more likely to experience any wheezing within the past year than kids with lower AGE scores. Secondary analyses showed that the higher meat eaters had more than double the risk of reporting wheezing that disrupted their sleep or wheezing that required prescription medication compared to their peers who ate less meat. (The data was not analyzed in a way to identify what specific quantity of meat intake was linked to these wheezing risks.) Bose says the link between higher AGE intake and wheezing existed even if kids had a healthy diet; in additional analyses the researchers controlled for factors such as body mass index, total daily caloric intake, and healthy eating index (HEI) scores. AGEs are found in most nonseafood meats, particularly after cooking at high temperatures, such as grilling, baking, searing, or frying. The compound is known to bind to a receptor in the lungs that mediates airway inflammation, but the role of dietary AGEs in asthma health overall is unknown, according to Bose.

Bose called the findings preliminary “hypothesis-generating” that needs a closer look. Future studies should prospectively look at kids over a longer period of time to see how dietary AGEs affect airway inflammation. John Carl, MD, the head of the Cleveland Clinic Center for Pediatric Pulmonary Medicine, called the findings provocative. “The mechanisms are very intriguing, but what’s being described here is an association and not causality,” he says. “We’re not ready yet to advise people [about changing meat consumption] other than for general health.” At one year, babies should be eating about 1.5 ounces of lean meat or beans daily. At 2 to 3 years old, the amount increases to two ounces, according to the American Heart Association. By ages 4 to 13, kids should be eating between three and five ounces of meat or legumes. One portion of meat is about two to three ounces or the size of a deck of cards. As a rule of thumb, red meats, such as beef, pork and lamb, have more saturated fat than chicken, fish, and plant proteins such as beans. RELATED: What We Know About the Link Between Obesity and Asthma Dr. Carl told Everyday Health that how meat is prepared may play a role in respiratory health, too. For example, if a parent is cooking meat with a lot of fumes, oils, and combustion products, inhalation of the smoke and vapors may exacerbate breathing problems in their children if they’re near the kitchen. Traci Gonzales, an ALA spokesperson, an advanced practice registered nurse, and a certified pediatric nurse practitioner in primary care at the Texas Children’s Hospital in Houston, says the most common symptoms of childhood asthma are a recurring cough, shortness of breath, and wheezing. Parents may notice kids’ symptoms worsen when they’re doing physical activity or at bedtime. “If ever parents have a concern that their child has asthma, they should have that evaluated. Look for patterns and keep a journal of symptoms,” she adds. “This research is useful, and we need more on the topic. We want to identify as many factors that we can that are modifiable to help lower a child’s risk of breathing problems,” Gonzales says. Genetics, a child’s environmental exposure, and a child’s history of infection are the trio of key factors that affect asthma risk, Carl said. Environmental exposures include allergens like dust mites, secondhand cigarette smoke, and pollen, mold and animal dander. RELATED: Kids With Disabilities or Developmental Delays May Have Increased Asthma Risk