Asthma can be defined as condition of lungs that may result in inflammation or swell ing and soreness of air passages.  Asthma and similar allergic ailments are substantially increasing at an alarming rate globally. Westernized countries and countries switching over to a westernized lifestyle have greater incidence of asthma in comparison to less advanced countries. Even though latest scientific studies reveal that the occurrence of asthma is at peak in developed countries, yet there are no explanations available so far for the same. Scientific studies reveal that the varying situations and the behavioural patterns linked with the so called “westernized” lifestyle are responsible for increase in the frequency of asthmatic attacks amongst general population. For example, due to upgrading in hygiene and management of infectious diseases, it is hypothesized that diminutive exposure to contagious agents during infancy can possibly lead to the development of asthma and allergies. Accordingly, few studies have publicized that exposure to markers linked with contagious and infectious agents like endotoxins, farm animals and pets can lessen the possibility of such ailments. Furthermore, some other attributes of the westernized lifestyle like Obesity and exposure to allergens have been related to the development of such disorders. Additionally, dietary changes which have happened over the periods amongst all age groups and in special conditions (pregnancy etc.), is another significant facets of modern lifestyle which have contributed to these conditions. 
Some of risk factors attributed by present lifestyle and leading to Asthma are:
- Diet and Nutrition
- Exercise(exercise induced asthma)
- Occupational Exposure
- Environmental Exposures: Indoor and Outdoor Air pollutants; Allergens
Obesity or excessive weight is one of the major lifestyle diseases. A large amount of scientific data reveals that Obesity is a causative factor for Asthma. The data is collected from adults, adolescents and children worldwide and specify an increased relative risk of asthma in the obese and overweight and express that Obesity predates Asthma. The mechanical basis of this correlation is not yet established. However, as per scientists viewpoint Obesity and Asthma share common etiology like common genetic predisposition, similar effects of in utero conditions, or that obesity and asthma are mutually the consequence of certain other predisposing factors such as physical activity or diet.
Moreover, research studies shows that obese patients have more severe asthma as compared to normal weight individuals and such severity can be due to greater respiratory inflammation, that is, airway obstruction or it can also be due to compact effects of asthma drugs or medications in Obese patients. 
Such patients are advised by physicians to follow a strict weight management schedule consisting of daily exercise and morning walk in order to have a healthier lifestyle.
Latest research on enhanced possibility of asthma after the commencement of habitual smoking all through upbringing and teenage years corresponds with the substantial data showing that active smoking results in unpleasant and severe respiratory health effects in adolescents and youngsters after a brief period of constant smoking. The fact that teenagers who smoke constantly have more severe symptoms and lessen lung function within the first few years of commencement has been acknowledged by researchers throughout the world. In addition to this, studies have proved that regular or continuous smoking enhances the possibility of asthma and other respiratory disorders and that significant long-term effects of smoking are not only restricted with those having a history of smoking for several years.
Moreover, recent clinical trial studies have established that paternal and maternal smoking (pregnant and breast-feeding mothers who are regular smokers) can lead to undesired health consequences on new-borns, childrens and young adults, making their body prone to asthma and other severe respiratory tractinfections.
Efficient tobacco control endeavours focusing on the control and prevention of smoking in children, teenagers, young adults, women of childbearing age and pregnant women are immediately required to prevent the severe cases of asthma in these people.
Diet and Nutrition
Scientific studies have established that a diet rich in marine fatty acids, peculiarly fish oil, can have valuable effects on inflammatory conditions like asthma.Also, fresh fruit eating can lead remarkable improvement in symptoms of asthma.Though, the influence of dietary salt reduction in the treatment of asthma is not yet established by researchers, but it has been concluded that there is significant improvement in pulmonary function with a low-salt diet. 
Exercise Induced Asthma
Exercise-induced asthma is defined as a state in which smooth muscles of the lungs starts contracting due to physical action. As a result, breathing becomes hard and a person physical performance declines inevitably. Exercise-induced asthma is more common in athletes who perform rigorous exercises as a part of their daily routine. The most common symptoms of Exercise-induced asthma are: wheezing, difficulty in breathing, chest tightness, coughing and problems with prolonged sessions of exercise.
The less common symptoms include stomach pain, nausea, inability to exercise in cold, chest congestion/discomfort, frequent colds, dry throat and headache
Proper warm –up or cool down may prevent or reduce the occurrence of Exercise Induced Asthma.Also, as environmental factors such as cold, dry air, high altitude, airborne allergens and food allergens like egg whites, peanuts, almonds or bananas, two hours before exercise can trigger an Asthma attack, it is highly advisable to perform exercises in finest circumstances or conditions characterised by warm, humid weather; negligible level of pollutants or allergens; and a moderate altitude. 
Substantial evidence of augmented or increased airway resistance is observed in normal individuals and asthamatic patients using medicines like propranolol and aspirin.Similar evidence has been seen in Asthmatic patients using Timolol eye drops for glaucoma.
Some other drugs which are known to provoke Asthma attack are: Cocaine, Dipyridimole, Hydrocortisone, Interleukin-2, Methylphenidate, Nitrofurantoin, Sulfasalazine, Protamine and Vinca alkaloids.
These drugs should be avoided as much as possible and should not be taken without prior approval or consultation of Physicians.
Present-day Working environment act as an add on to occupational respiratory diseases like Asthma due to inhalation of both organic and inorganic substances. Globally, Asthma is the prime diseases caused due to inhalation of organic agents. 
Commonly related occupations and exposures are: car painting (isocyanates), hairdressing (various chemicals), domestic and commercial cleaning(cleaning solutions), health care professionals(latex) and baking(flour dust), amongst many others.
Avoidance of such substances, especially for people working in industrialized environment is not easy. Thus, private and public sectors should implicate certain health policies, compensative and preventive measures for the well being of their laboured employees, contributing to the overall wellness of their companies.
Stressful life circumstances advances the symptoms of asthma. Studies have demonstrated the fact that concomitant parental and personal disputes enhances the possibility of Asthma at an early age, at a much higher rate in comparison to other risk factors like parental asthma, education and passive smoking..
Moreover, recent clinical findings have enumerated a range of emotional states as probable precursors of asthmatic symptoms. It was confirmed that distinct affective states like sadness or depression are predominantly related to an exasperation of sign and symptoms in individuals with asthma. Correspondingly, latest clinical trials have revealed that variant emotional and affective states such as anxiety, anger, and joy are similarly capable of eliciting increases in airway resistance in asthmatics. 
Indoor and Outdoor Air Pollutants:
Indoor Air Pollutants, basically indoor allergens, nitrogen dioxide, formaldehyde, volatile organic compounds, indoor generated particles and carbon monoxide can influence the respiratory system and can cause or aggravate the symptoms of asthma.
Similarly, long-term exposure to combustion related fine particulate air pollution is another significant environmental risk factor for respiratory diseases like asthma.
Here again, relative efforts are required by government and local public in general to combat the indoor and outdoor pollution by adopting a healthier lifestyle. 
Both indoor allergens like mites, some moulds, animal danders and insects and outdoor allergens like pollens and fungal moulds are found to exacerbate the symptoms of asthma and other respiratory disorders. Physicians recommend proper adoption of preventive control measures by general public to diminish the harmful affects of allergens on sensitive lungs.
Asthma can be defined as condition of lungs that may result in inflammation or swelling and soreness of air passages. Obesity, Smoking, Diet and Nutrition, Exercise (exercise induced asthma), Medications, Occupational Exposure, Stress and Environmental Exposures: Indoor and Outdoor Air pollutants; Allergens are some of the major risk factors attributed by current modernized lifestyle which are responsible for causing or alleviating the symptoms of Asthma. By adopting a healthier lifestyle, consisting of proper diet and resisting to harmful habits of smoking and use of undesired medications can help in combating the severe symptoms of Asthma. Furthermore, a prominent role is required by government and private sectors as well as by a common man to alleviate the detrimental effects of indoor and outdoor air pollution as well as the occupational and emotional stress; on sensitized lungs of a normal human-being.
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