Obesity is a major cause of shortness of breath in a weight loss setting. It exerts a negative stress on the respiratory, musculoskeletal and cardiovascular systems, and decreases the body’s ability to respond efficiently to exercise. Shortness of breath, or dyspnea, during the process of weight loss can also be a direct effect of improper diet, physical exertion or an ongoing disease process.
Obesity Hypoventilation Syndrome
Morbid obesity and sleep apnea are dominant risk factors for obesity hypoventilation syndrome, a disease of unknown cause that is characterized by shortness of breath and daytime drowsiness. People with this disorder have poor respiration, chronically low blood oxygen levels and high blood levels of carbon dioxide. Abnormality of the brain's respiratory center may play a role. Hypertension, right sided congestive heart failure and death can also occur.
Obesity and Shortness of Breath
People who are moderately overweight often complain of shortness of breath with exercise. It is not known whether the shortness of breath experienced by overweight persons who do not have obesity hypoventilation syndrome is related to obesity alone or if other factors such as de-conditioning are involved. As of 2010, doctors at UT Southwestern Medical Center and the Institute for Exercise and Environmental Medicine were conducting a study designed to determine whether shortness of breath in women in an exercise exercise setting is due to obesity or being out of shape.
Shortness of Breath is a Dangerous Symptom
Researchers at Cedars-Sinai Medical Center have found that shortness of breath can be a singular indicator of heart disease. A study published in the New England Journal of Medicine reports that shortness of breath was a significant predictor of death from heart problems and other causes. Obesity is a risk factor for coronary artery disease, and CAD can present as shortness of breath during weight loss. Weight management is a cornerstone in the treatment of CAD.
Sedentary Lifestyle and Shortness of Breath
People who are sedentary have hearts that are de-conditioned. The hearts and lungs of inactive people have to work harder to accomplish a given physical task. This de-conditioning can manifest as shortness of breath in a weight loss setting.
Kidney failure and hyperthyroidism are two disease states where involuntary weight loss can be part of the clinical picture. People with kidney failure can get shortness of breath due to anemia, fluid overload and congestive heart failure. In hyperthyroidism, the metabolic rate is increased, the pulse is rapid, blood pressure may be high, and muscle wasting can be present. These factors can combine to cause shortness of breath and weight loss. Uncontrolled diabetes can also cause pathological weight loss and shortness of breath.
Extreme diets that advocate a daily caloric intake of less than or equal to 800 calories per day can cause dangerous cardiac arrhythmia, which can manifest as shortness of breath, weakness, lightheadedness, loss of consciousness and death. Deprivation of essential amino acids, electrolytes, iron and folic acid can lead to muscle wasting and anemia. Red cells are essential for oxygen transport in the blood. In anemia the body compensates for the decreased number of oxygen carrying red cells by increasing the rate of respiration.