Shortness of breath can happen for many reasons. Low activity, extra pounds and long hours of sitting can all play a role. But ongoing symptoms may be due to asthma or other lung problems. It can be linked to anemia as well. Heart problems are another possibility, along with other conditions that involve the lungs or the heart and blood flow. Sometimes breathing trouble shows up before other clear signs appear.Why Do You Feel Breathless A clinician will try to sort out what is going on by looking at your pattern of symptoms. They may ask how fast it happens, when it begins and if it’s getting worse over time. They also inquire about other symptoms, such as pain or tightness in the chest, a persistent cough, wheezing, feeling lightheaded, unusual tiredness or swelling of the legs. A careful history and a physical exam can guide the next steps and whether tests are needed. More detailed checks are now available for breathlessness that has no clear cause. What gets done depends on what the doctor suspects. You might have oxygen level checks, blood tests, breathing tests, chest scans, an ECG, or an echocardiogram. In some cases, doctors may suggest a more focused look at the airways, such as bronchoscopy, or other procedures to find a specific problem and address it. Try not to panic every time you feel short of breath. Instead, pay attention to how your breathing has been changing from your normal pattern. If simple daily tasks that used to feel fine suddenly make you unusually breathless, or if the symptoms do not go away and start to get worse, it is a good idea to get checked by a clinician. Getting help sooner can support an early look at what is causing it and can help set up the right care. (By Dr Anjan Siotia, Director of Cardiology at BM Birla Heart Hospital)