Numerous conditions can negatively affect our respiratory system. Their effects may make it difficult to breathe, sleep, work, or play, overall making life difficult. In some cases, like cancer and COPD, these can even be fatal. This is why prioritizing our respiratory health is key for overall health and wellbeing. If you want to improve and maintain respiratory health, here are some guidelines to follow.

The respiratory system is essential – it provides the body with oxygen. After passing through the airways, oxygen and carbon dioxide are exchanged in the lungs. Oxygen is then transported to the different organs, while carbon dioxide is exhaled. 

These are the organs that comprise the respiratory system:¹

• Mouth and nose – These are openings that draw air from the environment into the body.
• Sinuses – Hollow areas between the bones of your head. They help regulate the temperature and humidity of inhaled air.
• Pharynx (throat) – Air from the nose and mouth passes through the pharynx to reach the trachea.
• Trachea (windpipe) – This passage conducts inhaled air to the lungs.
• Bronchi – These are large tubes at the end of the trachea that branch out and connect to your lungs. 
• Lungs – Lastly, these organs extract oxygen from the inhaled air and make sure it is delivered to the rest of the body. The lungs also exhale carbon dioxide, which is toxic if it accumulates in the body. 

How to Keep Your Respiratory System Healthy

Multiple factors² come into play with regard to lung health. Genes definitely affect the likelihood of acquiring or developing diseases (e.g., asthma, allergies³, in response to lung inflammation⁴, or chronic obstructive pulmonary disease (COPD)⁵), which is why it is common to see families with a lot of asthma or a history of lung cancer. 

The environment also plays a role in respiratory health. Growing up on a farm⁶ makes you more resilient to asthma and allergies.

But exposure to tobacco smoke⁷, occupational chemicals and dust (e.g., from mining⁸, working in a petrol station⁹, or due to metal¹⁰ or wood dust exposure¹¹), and air pollution¹² can all negatively impact our airways.

If you were prone to respiratory infections as a child¹³, this will also increase the risk of chronic respiratory disease as an adult. 

The negative interaction of all these elements brings about lung disease. However, there are steps you can take to keep your lungs clean and respiratory system healthy: 

Quit Smoking

Smoking causes narrowing and inflammation of the airways, making it difficult to breathe as well as increases your susceptibility to disease. This can destroy your lungs over time. Cessation is one of the simplest yet most effective ways to improve your respiratory health. More than 90% of lung cancer is linked to heavy smoking and within 5 years of cessation, the risk of lung cancer drops by nearly 40%. It is never too late to quit smoking.

Avoid Exposure to Toxic Indoor Pollutants

Chemicals¹⁴ from gas stoves, paint, and other home cleaning products can worsen lung disease. Improving ventilation¹⁵ can be done by using a range hood over the stove. Using a wall or ceiling exhaust fan can also increase ventilation, as well as opening windows and doors to improve air flow in the cooking area. For home cleaning products, keep these products tightly sealed and preferably in the garage or outside your home to limit exposure.

Be Wary of Outdoor Air Pollution

While being outdoors can be beneficial, pay attention to the quality of the air you are breathing. Exhaust fumes from cars, construction, and factory fumes may have toxic chemicals that can trigger lung disease. The American Lung Association¹⁶ recommends the following effective tips to protect yourself from air pollution:

Check daily air pollution forecasts in your area through local radio and TV weather reports. 

Avoid exercising outdoors, especially near high-traffic areas, when outdoor air pollution levels are high. Instead, work out in the gym or use an exercise machine at home. 

 Walk, bike, carpool, or use public transportation to lessen air pollution.

Maintain Good Hygiene

Here are simple but effective healthy habits we can build to keep ourselves healthy and avoid infections that can affect respiratory health:

• Wash your hands regularly with soap and water. Alcohol-based sanitizers are a good substitute.
• The mouth is a reservoir of bacteria. Good oral hygiene, like brushing your teeth twice daily and visiting your dentist, can decrease the likelihood of infection.
• If you are not feeling well, avoid going out. Take care of yourself and the people around you by staying home, taking a rest, and drinking plenty of fluids. 
• Get vaccinated whenever possible with the COVID-19 booster. Getting the yearly influenza vaccine will also help reduce the incidence of infection.

Healthy Diet

Conditions like gastroesophageal reflux disease (GERD¹⁷) can cause chronic cough, bronchial asthma, and pneumonia through acid reflux. Common symptoms include chronic cough, discomfort, bloating, and belching. To address GERD, you can alter your diet¹⁸:

Avoid: fried food, high salt levels, fatty meats, carbonated beverages, coffee, chocolate, and peppermint

Eat more: whole grains, root vegetables, green vegetables, bananas, melons, fennel, and nuts

Get Vaccinated

Vaccines¹⁹ have been proven to be safe²⁰ and can drastically reduce the severity²¹ of diseases. Although side effects can occur, most of these are mild and resolve on their own in a few days. Getting vaccinated against the following diseases will be a huge help for your lung health in the long run:

• COVID-19
• Haemophilus influenza type b (Hib)
• Influenza (flu)
• Measles
• Pertussis (whooping cough)
• Pneumococcal disease
• Varicella (chickenpox)

Breathing Exercises

The lungs lose their “elasticity” over time, and especially when directly affected by respiratory disease. This not only makes it difficult to breathe but affects the quality of air moving through our lungs. Doing these breathing exercises²² will not only get rid of accumulated stale air in your lungs but also increase oxygen levels: 

• Pursed lip breathing – Breathe in through your nose and breathe out twice as long through pursed lips
• Belly breathing (diaphragmatic breathing)²³ 

Lie on your back with your knees bent. Use pillows to support your head and knees for comfort. 

Place one hand on your chest and the other on your belly, below the rib cage.

Inhale slowly, filling your belly. The hand on your chest should remain still while the other hand rises with your belly.

Tighten the abdominal muscles and let them fall inward as you exhale through pursed lips. The hand on your belly should return to its original position. 

Note: Practice this technique for 5-10 minutes several times a day. If doing these exercises regularly, you can learn to breathe better.

Airway Clearance Techniques

Conditions like cystic fibrosis lead to the production of thick, sticky mucus that can block the lungs. Airway clearance techniques²⁴ use a combination of coughing and huffing to clear the airways, decrease lung infections,²⁵ and improve lung function.

Exercise Often

Exercise has numerous benefits.²⁶ One of these is maintaining our lungs’ health, even for those with cystic fibrosis²⁷ or lung cancer.²⁸ It not only improves our physical health, but also positively impacts our mental, emotional, and even social health. You can go hiking, swimming, dancing, boxing, to the gym, or any other activity that you find fun and pleasant. Your lungs will definitely thank you for that workout! You can even exercise with a cough, but be careful not to go overboard. If you're not feeling too well, then leave the exercise for days when you feel 100%.

Visit Your Doctor Regularly

Frequent outpatient visits²⁹ reduce the risk of exacerbation of diseases like COPD by a sizable 45-60%. Lung diseases can go undetected until they become a serious problem. This is why you should not skip your annual physical exam, even if you are feeling well.

Common Respiratory Conditions

We group respiratory conditions according to the duration of illness. Acute diseases usually last for a few days to weeks (less than 15 days), while chronic conditions last for weeks to months. This next section will provide a rundown of the most common acute and chronic respiratory conditions.

Acute Respiratory Illnesses

Common Cold

Also known as rhinopharyngitis,³⁰ the common cold³¹ is an inflammation of the airway lining. It is often due to viruses like rhinoviruses, coronaviruses, and adenoviruses. About 50% of upper airway infections are attributable to the common cold. It can occur at any age, last a couple of days to a couple of weeks, have a wide range of symptoms, and lead to complications like ear infections, eye infections, and even pneumonia. Acetaminophen³² can help lower fever to aid recovery, alongside adequate rest and increased fluid intake. 

Sinusitis

This is a common illness-causing inflammation in the sinuses. Sinuses³³ are the hollow spaces behind the facial bones. These include the areas behind your cheeks, forehead, and nose. The usual complaint in sinusitis³⁴ is a runny nose, as well as pain when pressing on your face, cough, fatigue, fever, and headaches. Viruses are the primary culprit in this disease. Within two to three weeks, symptoms typically improve. 

Bronchiolitis

Bronchiolitis³⁵ is a common lung infection in babies and children. It causes inflammation and congestion of airways, making airflow into and out of the lungs difficult. Coughing, wheezing, and difficulty breathing can last for a few days to weeks. Children are more often affected because their lungs and immune system have not yet fully developed. Those at greater risk of infection include infants who were premature at birth, have an underlying heart or lung condition, and those who are bottle-fed and not breastfed (as breastmilk is a rich foundation for the child’s immunity).³⁶ 

Pneumonia

Pneumonia³⁷ is a condition causing inflammation of the lungs, leading to the pooling of fluid or pus. This leads to cough, fever, chills, and difficulty breathing. Bacteria, viruses, and fungi can all cause pneumonia. People with lowered immunity are at greater risk of pneumonia, including babies, elderly people, and those with HIV. Certain lifestyle changes can help pneumonia patients.

COVID-19 

Coronavirus disease (COVID-19³⁸) is a respiratory disease caused by SARS-CoV-2 virus. Most people will experience mild to moderate symptoms similar to a cold and recover without treatment. However, the elderly and people with underlying medical conditions may develop more serious illness. COVID-19 spreads when infected people speak, cough, or sneeze. To protect yourself and others, wear a mask, wash your hands frequently, and stay at least 1 meter apart from others. Practice respiratory etiquette by coughing into your elbow. Self-isolate if you are not feeling well and contact your doctor. 

Influenza (Flu)

This is a viral infection that targets the nose, throat, and lungs. The flu³⁹ usually resolves on its own but complications can be deadly. Common signs and symptoms include fever, cough, aching muscles, chills, and sweats. Consult your doctor if you experience difficulty breathing, chest pain, dizziness, and seizures. 

Chronic Respiratory Conditions

Asthma

Asthma⁴⁰ is a major non-communicable disease that affects both children and adults. It causes a narrowing and inflammation of the airways, making it difficult to breathe. This can significantly impact physical, mental, emotional, and even social health. Worldwide, asthma affected almost 262 million people in 2019 and caused about 455,000 deaths. Management of asthma emphasizes avoiding triggers as much as possible to prevent attacks. Inhaled medications can also be prescribed to ensure a better quality of life.

Chronic obstructive pulmonary disease (COPD) – 

COPD⁴¹ is a common and preventable lung disease that affects both men and women worldwide. The two types are emphysema ⁴²and chronic bronchitis. Destruction of the lungs, mucus build-up and blockage, and inflammation all lead to impaired airflow in and out of the lungs. Like asthma, patients can present with cough, wheezing, and difficulty breathing, and some people have both conditions. COPD is the third leading cause of death globally and led to 3.23 million deaths in 2019. Risk factors for COPD include exposure to tobacco smoke, air pollution, and occupational dust and fumes. To curb disease progression and occurrence of symptoms, it is important to quit smoking. Early detection, diagnosis, and treatment are also pillars of COPD management.

It is evident that there is a lot to consider when it comes to lung health. It pays to be conscious of our own habits that might be negatively affecting our health, such as smoking or exposure to toxic substances. We have to be vigilant not only in addressing these potential causes of disease, but also in consulting a doctor before your symptoms get out of hand. 

What Are the Most Common Causes of Respiratory Problems?

Research on the causes of lung disease continues to help us understand risk factors, treatment, and prognosis. While we may not know everything yet, these are the leading causes of respiratory problems⁴³ today:

Smoking

The toxic products from smoking cigarettes, cigars, and pipes are the primary cause of lung disease. The recommendation is to quit smoking, or do not start the habit at all. Vaping is likely no better⁴⁴ for you. Avoid secondhand smoke as much as possible by asking smokers to smoke outside. Secondhand smoke has a particularly harmful impact on babies and young children.

Radon

This naturally occuring gas⁴⁵ is colorless, odorless, radioactive,and deadly. It is often present in homes and can cause lung cancer. One way to check for the radon levels in your house is to buy a kit that you can find in most hardware stores. 

Asbestos

This is a mineral fiber that was used for insulation, fireproofing, and car brakes. However, minute asbestos particles can harm the lungs, causing scarring of the tissue that can lead to lung cancer. It is no wonder then that 55 nations⁴⁶ around the world have banned asbestos due to the serious health risks involved. The risk of lung disease from asbestos exposure is vastly increased if you also smoke.⁴⁷

Household air pollution

Solid fuels⁴⁸ like wood, crop waste, and charcoal are still in use by 2.6 billion people to cook food. Toxic fumes and soot particles can penetrate the lungs, affecting tissue integrity. Almost 4 million people a year die from indoor air pollution exposure. The use of solid fuels and kerosene for cooking has been linked to pneumonia, COPD, stroke, ischemic heart disease, and lung cancer.

Outdoor air pollution

The rise of air pollution⁴⁹ in both urban and rural areas is a major environmental health problem. Fine particulate matter can lodge in the lungs and can cause cardiovascular and respiratory diseases, as well as cancer. The majority of the affected population are people in low- and middle-income countries, accounting for 4.2 million deaths. Factors such as policy-making, transport, energy, waste management, and agriculture all come into play in air pollution. Thankfully, policies aimed at lowering harmful emissions and promoting clean technologies are steadily gaining ground to address this public health issue.

Seasonal fires

Wildfires⁵⁰ have been increasing in frequency and have a negative impact on a changing climate. The fine particulate matter produced in these fires can penetrate deep into the lungs and cause disease. This can cause exacerbations of underlying respiratory and cardiovascular disease. 

 Clearly, the health effects brought about by the environment is a serious problem. Thankfully, policies aimed at lowering harmful emissions and promoting clean technologies are steadily gaining ground to address this public health issue.[1] [m2]  On an individual level, each person can do their part to mitigate disease and reduce potential sources of infection. Small steps now can ensure the health of future generations as well as our own. 

How Are Respiratory Problems Diagnosed?

Common symptoms of lung infections include cough, fever, hoarseness, fatigue, red eyes, runny nose, and a sore throat. These may last for a few days or up to one to two weeks. They usually go away on their own, especially when treated with rest, fluids, and over-the-counter medications. 

During this period, it is important to stay home and avoid going out, as you may be infectious. Diseases can easily spread when people sneeze or cough without covering their nose and mouth. Germs may linger in the air and other people can inhale them, causing infection. 

If your symptoms last longer than two weeks or appear to worsen, it might be time to call your doctor. 

Upon consulting with your doctor,⁵¹ the first step is a thorough history-taking and physical examination. Your doctor will ask you for details about your symptoms, including their description, severity, timing, and progression. A physical examination will be conducted to check your overall health, with emphasis on your nose, ears, throat, and chest to assess breathing. Once your healthcare provider has ascertained you do have a respiratory infection, they may request the following lab tests to confirm the diagnosis:

• Chest x-ray
• Chest CT scan
• Pulmonary function tests
• Nasal swab
• Throat swab
• Sputum test

The results of these tests will ultimately determine the final diagnosis and direct treatment. 

If your infection is bacterial, you may be prescribed antibiotics. Viral infections do not respond to antibiotics, therefore you will not be prescribed them. Instead, you may be prescribed antiviral medications⁵² to help with the symptoms. These drugs work best when taken within two days of getting sick. Medications taken within this time frame can lessen symptoms and shorten your illness duration by one day. Antivirals are not sold over the counter and requires a prescription from a health care provider. Here are the four FDA-approved antiviral drugs recommended by the Center for Disease Control and Prevention (CDC):

• Oseltamivir phosphate (Tamiflu)
• Zanamivir (Relenza)
• Peramivir (Rapivab)
• Baloxavir marboxil (Xofluza)

Important note: This information is not intended to replace a medical consult. Consult your doctor before taking these drugs.

Taking antibiotics when unnecessary, failing to complete a prescribed course, and/or self-medicating with antibiotics left over from a previous prescription leads to the development of antibiotic-resistant bacteria.⁵³ This means that bacteria evolve in such a way that we can no longer easily treat them. Antimicrobial resistance continues to pose an alarming threat⁵⁴ to health, with about 10-15% of the pneumonia-causing bacteria Streptococcus pneumoniae now demonstrating resistance to commonly used antibiotics. Ways to avoid contributing to this trend are: only taking antibiotics as ordered by your doctor and always completing the full course of prescribed antibiotics. When your doctor has not prescribed antibiotics, it’s best to focus on treating the symptoms to gain relief. 

Lung Health Key Points⁵⁵

• COPD affects 384 million people each year and causes 3 million deaths, making it the third leading cause of death worldwide.
• Lung cancer is the deadliest cancer, accounting for 1.76 million deaths.
• Asthma affects 14% of children across the globe and the numbers continue to rise, making it the most common chronic disease of childhood. 
• Pneumonia is the leading cause of death in the very young and very old.
• Passive smoke exposure leads to respiratory disease. It also leads to 2.5 million deaths in non-smokers.
• 91% of the world’s population live in places where air quality is not up to par with the WHO guideline limits. 

Final Thoughts

Health is everyone’s business. Organizations worldwide are taking measures to curb the rise of respiratory illnesses. Disease prevention strategies, including reducing air pollution and helping people quit smoking, are key measures to reducing deaths due to COPD. Interventions have also been formulated to target at-risk groups, such as elderly people with pneumonia and coal miners with pneumoconiosis. Lung cancer screening rates have been increasing, which can greatly reduce deaths due to lung cancer through early detection and treatment. On an individual level, we can take small but meaningful steps to protecting our respiratory health by ensuring a clean environment and engaging in regular exercise, a healthy diet, and adequate sleep. In this time of pandemic, we should be vigilant with any symptoms we or our loved ones are experiencing and take appropriate measures to mitigate the spread of disease.

If there is anything the COVID-19 pandemic has taught us, it is that health is wealth. We all know how awful it feels to be sick; it affects our sleep, skin health, mood, appetite, and overall ability to function. Taking the simple measures discussed in this article will definitely go a long way to keeping ourselves and our loved ones safe. If you are not feeling well, consult your physician immediately.

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Mikaela Millan

Mikaela is a dentistry clinician at the University of the Philippines.