Does Being Overweight Affect Asthma?

Have you ever asked yourself or your healthcare provider “does weight affect asthma?”

While it might not seem like much, gaining 5 just pounds has been shown to worsen asthma control and quality of life. In one study published in the journal Respiratory Medicine, gaining 5 pounds, compared to those who gained less or lost weight, was associated with:

  • 22% poorer self-rated asthma control
  • 18% poorer self-reported quality of life
  • 31% increase in the odds of requiring a steroid burst

The authors concluded that “strategies to prevent weight gain could help patients achieve better asthma control and improve asthma-related quality of life. A clearer understanding of the mechanisms by which body weight/BMI influences asthma control and other asthma-related outcomes will enable treatment specialists to formulate treatment programs that include a weight-management component.”

In fact, few studies have rigorously examined treatments in overweight or obese asthmatics or the impact of weight loss in asthma.

Person standing on a bathroom scale
John Fedele / Blend Images / Getty Images

Weight Leads to Different Responses to Asthma Medications

In this scenario, weight has a direct impact on asthma control. While there have not been studies specifically targeting overweight or obese asthmatics, obese patients do not appear to respond to controller medication in the same manner as non-overweight asthmatics. On the other hand, response to rescue medications is not altered. Not surprisingly, current research in asthma has not targeted obese patients specifically, and this should be a target of future clinical research. Currently, there are no recommended treatment differences based on your weight.

Does Weight Loss Affect Asthma?

Several studies have suggested that weight loss from bariatric surgery improves asthma control in obese patients. One study found that medication refills decreased by as much as 50% following bariatric surgery. More recent publications have demonstrated improvements in asthma symptoms as well as pulmonary function tests 5 years following surgery. One of the main limitations of all studies involving bariatric surgery and asthma is a small size, limiting the generalizability of the results.

While these reports are promising, bariatric surgery is a fairly radical step. The procedure has its own risks and complications. If lifestyle modifications targeting weight loss produce similar results, surgery is not worth the risk.

A small randomized clinical trial (RCT) that involved diet and exercise demonstrated improved quality of life in 83% of participants and asthma control in 58% of participants following a 5–10% weight loss. In the dietary intervention, participants consumed 2 meal replacement shakes, one main meal, and 2 snacks per day, along with receiving dietary counseling. In the physical activity, intervention patients received a gym membership and 1 hour per week of personal training with a tailored physical activity program. While this study and a few others are promising, to date, no large, multi-center trials have been undertaken to see if these results can be replicated.

Implications for You

While we cannot recommend weight loss for asthma specifically in overweight and obese patients, we can recommend weight loss for these patients in general. Patients in small studies have achieved meaningful improvements in asthma outcomes with weight loss. Any overweight or obese patient should attempt weight loss after appropriate medical consultation.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

By Pat Bass, MD
Dr. Bass is a board-certified internist, pediatrician, and a Fellow of the American Academy of Pediatrics and the American College of Physicians.