Impact of Processed Meat on the Symptoms of Asthma
Processed meat contains nitrites (food additive
), which cause inflammation in the airway - a typical feature of asthma.
‘A common food additive found in processed and cured meats called nitrites can cause inflammation in the airway, thereby worsening asthma symptoms.’
The research team collected data from the participants involved in the French Epidemiological study on the Genetics and Environment of Asthma (EGEA), to study whether intake of processed meat was associated with the worsening of asthma symptoms. The study involved more than 2000 asthma patients and their close relatives. The comparison groups were from five cities in France for more than 20 years. The participant's health was tracked through surveys and medical examinations.
Data Collection for the Study
For the current study, dietary intake, body weight (BMI), asthma symptom score and demographic data of 971 adults were obtained up to 2011-2013.
- Food frequency questionnaire was used to measure the dietary intake. The questions encompassed 118 items in 46 food groups. Cured and processed meat intake (ham, sausage, and salami) was classified as low, medium and high. Low for less than one weekly servings; medium for 1-4 weekly servings and high for 4 or more.
Asthma Symptom Score
- The score for asthma symptoms such as breathing difficulty, shortness of breath, and chest tightness in the preceding 12 months were scored from 0 to 5.
Information on other influential factors such as smoking, physical activity, age, gender and educational qualification were also gathered.
Findings of the Study
About 42% of the participants had asthma at some point and around half (51%) had never smoked between 2003 and 2007. One-third (35%) of the participants were overweight, and one in 10 (9%) were obese.
On an average, participants consumed 2.5 servings of cured or processed meat per week.
Between 2011 and 2013, the medical examinations were made. The findings showed that
- There had been no change in asthma symptom score for 513 (53%) of the participants
- About 20% (one in five) of the participants had worsened asthma symptoms, and 27% (one in four) had improved symptoms of asthma
- Participants who ate one serving of processed meat per week had worsened symptoms of asthma by 14%
- Participants who ate more than one serving of processed meat per week had worsened symptoms of asthma by 20%
- The symptoms worsened the most for participants who ate more than one servings of processed meat per week by 22%
After adjusting other influential factors such as age, gender, physical activity, smoking, and educational qualification, the participants who ate the most cured and processed meats were 76% more likely to experience worsening symptoms of asthma than those who ate the least serving.
Previously conducted studies have linked overweight and obesity to worsening symptoms of asthma. In the current study, obesity and overweight worsened the asthma symptoms by 14%.
The researchers concluded that this is an observational study and no firm conclusions can be drawn about cause and effect. The limitation of the study is that the survey was based on the memory and the asthma symptom score may have been affected by smoking and COPD (chronic obstructive pulmonary disease), which has similar symptoms associated with asthma. However, the research points to the potential role of cured and processed meat in respiratory function and health.
"This research extends the deleterious effect of cured meat on health, and the effect of diet on asthma in adults, and provides a novel analytic approach regarding the role of BMI in the diet-asthma association," they conclude.
The research is published in the journal Thorax.
is a respiratory condition in which the airways are inflamed, narrow and produce extra mucus. Wheezing, shortness of breath, coughing, and chest tightness are the common symptoms of asthma.
- Globally, 334 million people have asthma
- One in 12 Americans have asthma
- More than 1 million new asthma cases are reported in India every year
- Women are more likely suffer from asthma than men