The relationship between diet, gut microbiota, and lung health has come under scrutiny in an ongoing investigation involving New York City firefighters who responded to the World Trade Center site in the aftermath of the September 11, 2001 attacks.
Data from the FIREHOUSE study (Food Intake Restriction for Health Outcome Support and Education) have revealed intriguing insights. Among the NYC firefighters who participated in a microbiome substudy within FIREHOUSE, those who adhered to a low-calorie, Mediterranean-style diet exhibited elevated levels of Bacteroides ovatus in stool samples after 6 months. This bacterial species is associated with protection against bowel inflammation.
Conversely, participants who adhered to a usual care diet displayed increased levels of a species linked to high-fat diets and inflammation, according to Rachel Lam, a predoctoral fellow in the Nolan Lab at NYU Langone Medical Center in New York City, who presented the findings at the American College of Chest Physicians (CHEST) annual meeting.
“In our validation cohort, Bacteroides ovatus was increased in the LoCalMed arm after 6 months, and this bacterial species is associated with fewer negative health effects,” noted Lam.
Lam highlighted the results from a murine model of high-fat diets, where mice administered with Bacteroides ovatus experienced reductions in body mass index, as well as decreased serum LDL cholesterol and triglyceride levels.
The FIREHOUSE study, led by senior author Anna Nolan, MD, explores predictors of lung function loss in a group of firefighters who were exposed to the particulate matter at Ground Zero on 9/11 and in the days that followed. These preliminary findings align with prior research indicating potential connections between intestinal microbiota and lung function.
Dr. Nolan explained, “It’s interesting that we saw this done in other models, like mouse models and such, where certain bacteria were viewed as healthy for the system, and if they were able to bring that bacteria out in larger amounts, they saw anti-inflammatory effects, so we’re hoping to mirror that and also do a mouse model.”
Dr. Nolan’s team had previously identified markers for metabolic syndrome, inflammation, and vascular injury in serum samples taken within 6 months of the 9/11 events as predictive factors for future abnormal lung function. Elevated serum levels of an LDL metabolite after intense World Trade Center dust exposure were also found to be a risk factor for future impaired lung function, as measured by forced expiratory volume in 1 second (FEV1).
In the FIREHOUSE trial, 89 patients were randomly assigned to a technology-supported educational and behavioral intervention focusing on calorie restriction for weight loss while adhering to a low-calorie Mediterranean diet. The control group received usual care, consisting of general advice on healthy eating without specific dietary assignments.