Guest Author - Cheryl Tidball, DO

It has been known for some time that being overweight or obese can increase one’s chances of developing certain chronic health problems such as heart disease, diabetes, rheumatoid arthritis, and certain types of cancer. Researchers have also noticed that as the incidence of obesity is rising over the last few decades, so is the incidence of asthma and allergic diseases. Although this relationship could be purely coincidental, there are several factors which may indicate a potential association.

Overweight individuals have been noted to have increased gas trapping in their lungs and a decreased inspiratory capacity as their body mass index (BMI) increases. These problems may lead to other respiratory problems other than asthma including sleep apnea and more frequent respiratory infections. Esophogeal reflux, often referred to as heartburn, is more common as well and is known to be a trigger for many asthmatics.

Changes in dietary habits in industrialized nations may also be a factor in the development of asthma. Researchers have found that certain fatty acids such as linoleic and eicosapentaenoic acid may reduce the inflammatory mediators that are associated with asthma. Interestingly, the incidence of atopy, or allergic skin reactions, is not increased in overweight individuals, which means that some of the usual allergic pathways involved in the development of asthma attacks are not a part of this inflammatory response.

Other hypotheses that have been made are possible genetic factors as well as hormonal factors. It has been noted that a hormone called leptin, which is produced by fat cells and has been found in higher concentrations in overweight individuals, also has an effect on the inflammatory response and may influence asthma.

Although the relationship between obesity and asthma is not well understood, it is clear that losing weight may be just as if not more important than continually increasing anti-inflammatory medications in certain individuals. Asthmatics may have special difficulties losing weight including the use of oral steroids which are well known to cause weight gain. Often asthma symptoms are aggravated by increased activity, which may make it difficult to exercise. Asthmatics should consult with their physician before beginning any weight loss program. Although losing weight is difficult, it may dramatically improve an asthmatic’s health and ability to enjoy life!