Blue light emitted by devices like smartphones, computers, and televisions is becoming a major factor disrupting our sleep cycles. Research reveals that a significant number of Americans use electronic devices close to bedtime, contributing to poor sleep quality. Reducing exposure to blue light, particularly in the evening, is a simple yet effective way to help your body prepare for restful sleep.

What Is Blue Light?

How Does Blue Light Impact Circadian Rhythms?

Circadian rhythms are 24-hour cycles that control essential bodily functions, including sleep. Light is the primary factor that aligns these rhythms with day and night. Historically, exposure to sunlight during the day helped set our body clocks, signaling when to be awake and when to sleep. However, the widespread use of artificial lighting and electronic devices has introduced more light exposure after dark, disrupting these natural cycles.

Blue light, in particular, has the strongest impact on circadian rhythms. During daylight hours, blue light helps us feel alert by stimulating the brain, raising body temperature, and increasing heart rate. But in the evening, exposure to blue light can confuse the body’s internal clock, suppressing melatonin—the hormone responsible for making us feel sleepy. As a result, our brains may remain in “daytime mode,” preventing us from winding down for the night.

Health Consequences Of Disrupted Sleep

Persistent disruption of circadian rhythms can lead to a range of health issues, including metabolic disorders, poor mental health, and increased risk for conditions like depression and anxiety. Furthermore, the inability to sleep well at night affects cognitive performance, mood, and overall well-being. Chronic exposure to blue light in the evening may significantly contribute to these negative health outcomes.

Devices That Emit Blue Light

Many common devices in our daily lives emit blue light, including:

- Smartphones and tablets

- Computer monitors and laptops

- Televisions and e-readers

- LED and fluorescent lighting

- Video game consoles

How To Minimize Blue Light Exposure

To reduce the effects of blue light on your sleep, here are some practical strategies:

1. Turn off screens before bed: Try to avoid using electronic devices at least two to three hours before bedtime. Reducing screen time helps prevent blue light from interfering with melatonin production.

2. Adjust your lighting: Dim your home’s lights or switch to warmer-toned lighting in the evening. You can also use lamps with red or orange light, which are less likely to impact your circadian rhythms.

3. Night mode settings: Many smartphones and computers have a "night mode" feature that reduces blue light emission. Make use of these features to limit exposure in the hours leading up to bedtime.

4. Blue light-blocking glasses: Special glasses designed to filter out blue light may be helpful for some individuals. These glasses can block or reduce the melatonin-suppressing effects of blue light.

5. Apps for blue light reduction: There are several smartphone and computer apps available that reduce blue light emission, allowing you to use your devices before bed without disturbing your sleep.

6. Create a sleep-friendly environment: If you can’t control light sources in your bedroom, consider using an eye mask to block out ambient light and promote better sleep.

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)

Quitting smoking may give your lungs a chance to recover, but not all damage can be reversed. On World Lung Day, doctors explain the healing process in all kinds of smokers, from those who have one cigarette per week to those who went through ten packs a day.

Find out why former smokers cough more after quitting, and when lung damage becomes irreversible.

Every cigarette exposes the lungs to a mixture of toxic chemicals that can cause inflammation of the airways, deteriorate their natural cleaning system and, over time, damage the lung tissue itself.

Some effects of smoking can improve substantially after quitting. Airway inflammation may settle down, excess mucus can decrease, the cilia that clear particles from the respiratory tract can regain function, and symptoms such as cough and breathlessness may improve. Quitting also stops the continued exposure responsible for the accelerated loss of lung function.

But when smoking has already destroyed lung tissue, particularly in emphysema, the damage cannot simply be reversed.

“Smoking-related lung damage is not an all or none phenomenon,” Dr Swapneel Mehta, Sr. Consultant, Pulmonology, Dr LH Hiranandani Hospital, Mumbai told HealthandMe.

“The lungs do begin to recover after the last cigarette, although the extent of recovery depends on how much damage has already occurred.”

The Recovery Process Starts Soon

Although different parts of the respiratory system recover at different rates and speed, the body starts responding after you quit smoking almost immediately.

In a conversation with HealthandMe, Dr Tejveer Singh, HOD, Respiratory, Sleep Medicine & Interventional Pulmonology, Bhagwan Mahavir Manipal Hospital, Ranchi, said carbon monoxide levels in the blood start falling within hours of quitting. This allows oxygen to be transported more effectively.

Over the following days and weeks, irritation and inflammation in the airways can gradually decrease. Cough, phlegm and breathing difficulties may subsequently improve.

Dr Prasanna Kumar T, HOD & Consultant, Respiratory Medicine, Ramaiah Memorial Hospital, told HealthandMe about the changes in the lungs' mucociliary clearance system, which helps remove mucus and inhaled particles from the airways. He said studies have found measurable improvement in mucociliary clearance after smoking cessation, with some research reporting significant improvement within the first month and further gains over longer periods.

He said, “Ciliary and mucociliary functioning, the recovery starts and there are certain studies that were published shows that nasal mucociliary escalator or clearance which may return to normal range by day 15 post stopping smoking with benefit sustained to up to 180 days, that is 6 months. Well, there are other studies which also show that 63% of the people who quit smoking showed significant improvement in this mucociliary clearance at end of one month raising up to 85% at the end of 12 months.”

He added, “So, there is definitely a measurable gain in the lung function which is measured by spirometry and there is reductions in the cough and the breathlessness which is actually the basic symptomatology which will typically emerge over 2 weeks to 3 months as there is evolution of airway inflammation and bronchospasm can also subside.”

Also read: FDA To Speed Up Approval Process For Vapes & Nicotine Pouches: Does It Mean They Are Safer Than Cigarettes?

Quitting Can Make You Cough More At First

The lungs have their own cleaning system. Mucus traps dust, microorganisms and other inhaled particles, while microscopic hair-like structures called cilia move that mucus upwards, allowing it to be coughed out or swallowed. Smoking damages this system, reducing the effectiveness of ciliary movement.

Once smoking stops, ciliary function can gradually recover. As the airways become better at moving accumulated mucus and particles out, coughing and sputum production can temporarily increase. Dr Singh said this is an important distinction for people who have recently quit.

He said, “After smoking stops, ciliary function can gradually improve, helping the lungs clear mucus and trapped particles more effectively. This is one reason some people cough more during the initial period after quitting.”

Dr Kumar explained that different parts of the airway immune system recover at different speeds. Ciliary function can improve earlier, while changes in the physical properties of mucus may take considerably longer. Over time, better airway clearance can contribute to fewer respiratory symptoms and may reduce chances of respiratory infections.

Also read: It’s Not Just Tobacco: The Hidden Oral Cancer Risks We Rarely Talk About

Occasional Smoking Versus Years Of Chain Smoking

The amount and duration of smoking matter because smoking-related lung damage accumulates over time. Doctors often quantify exposure using pack-years, which takes into account both the number of cigarettes smoked and the number of years a person has smoked.

Someone who has smoked occasionally is less likely to have developed extensive structural damage. If smoking is stopped before substantial lung-function loss occurs, there is greater scope for recovery and preservation of remaining lung function.

Repeated exposure can cause chronic airway inflammation, thickening and remodelling of the airway walls, destruction of the attachments around the alveoli and progressive airflow limitation. Dr Kumar described this as a dose-response relationship rather than simply a question of how many years someone has smoked.

“The message here is by quitting smoking, there would be some changes that can be seen as a trajectory moving forward at any stage of stopping the smoking,” he said. “But what you should understand is that it does not reset the starting point in long-term smokers.”

The classic Fletcher-Peto curve is often used to illustrate this concept. Lung function naturally declines with age, but in smokers the decline can become much faster.

Dr Mehta explains, “With prolonged and heavy smoking, however, the risk of COPD, emphysema and irreversible loss of lung tissue increases. The classic Fletcher Peto curve helps explain this. Lung function, measured by FEV₁, normally declines gradually with age. In susceptible smokers, this decline can become much steeper.”

He added, “The earlier someone quits, ideally before significant loss of FEV₁ has occurred, the greater the opportunity to preserve the lung function they still have. At the same time, it is important to remember that the Fletcher Peto curve is a conceptual model and that individual rates of lung function decline can vary considerably.”

Also read: Never Smoked, Still Got Lung Cancer? Rare Gene Mutation Linked To Over 60x Risk

What Can Actually Reverse, and What Cannot?

Lung recovery can be explained by understanding functional and inflammatory changes from smoking-related destruction. According to the doctors, changes that can improve after quitting include:

• Airway inflammation
• Excess mucus production
• Poor mucus clearance
• Ciliary dysfunction
• Some amount of airflow limitation
• Cough, phlegm and breathlessness

Structural destruction of the lungs includes emphysema. In emphysema, the walls of the alveoli, the tiny air sacs where oxygen and carbon dioxide are exchanged, are destroyed. Those damaged air sacs do not simply grow back after a person quits smoking. Established fibrosis, airway remodelling and fixed airflow limitation can also become permanent.

Dr Mehta put it simply, “This is where it is important to understand the difference between inflammation and actual structural damage. Airway inflammation, excess mucus production and impaired mucus clearance can improve after quitting. Lung function may also improve to some extent,” he said. “However, when emphysema has destroyed the walls of the alveoli, those air sacs do not regenerate.”

Dr Kumar similarly pointed to the distinction between reversible airway changes and established lung parenchymal damage. “The 2026 GOLD report explicitly points out that once there is lung parenchymal damage in COPD, lung function rarely recovers fully,” he said.

The 2026 Global Initiative for Chronic Obstructive Lung Disease (GOLD) report is the current evidence-based strategy document for COPD prevention, diagnosis, and management.

Also read: 9/11: US CDC To Launch Health Study Of Exposed Children By 2027

Feeling Better Does Not Mean Lungs Have Fully Recovered

One of the more deceptive aspects of smoking-related lung disease is that symptoms and lung damage do not always move together. A person may stop smoking, notice that their cough has disappeared and find that they can climb stairs without feeling breathless. That is good news, but it does not necessarily mean that every underlying damage from smoking has reversed.

“The lungs have considerable functional reserve, so early airflow limitations or structural changes may remain unnoticed until a substantial amount of function has been affected,” Dr Singh said.

Dr Mehta similarly cautioned that symptoms are not always a reliable indicator of early lung injury. “Feeling well does not necessarily mean that the lungs are completely healthy,” he said.

This is where testing becomes important for people with a significant smoking history or relevant symptoms. Doctors use various types tests to measure how much air a person can breathe out and how quickly they can do it, helping doctors identify airflow obstruction.

Spirometry is one of the key tests. Depending on the clinical situation, doctors may also consider:

• Diffusing capacity testing (DLCO): can provide information about how efficiently gases move from the lungs into the blood.
• Chest imaging: can identify structural abnormalities that may not be apparent from symptoms alone.
• Oxygen or gas-exchange assessment: may be used when clinically indicated.
• Low-dose CT: may have a role in selected people at high risk of lung cancer and can also reveal structural abnormalities.

Dr Kumar said the practical message for people with a substantial smoking history is straightforward - “Feeling better is not the same as being cleared.”

Other Factors That Slow Down Lung Recovery

Former smokers may continue to encounter second-hand smoke, air pollution, biomass smoke, construction dust, industrial fumes and other occupational irritants. These exposures can sustain airway inflammation and aggravate respiratory conditions. Dr Kumar described recovery as something that can be affected when the airways remain under chronic irritation.

“Recovery is not a one-way door if the airway remains under chronic assault,” he said.

Dr. Singh cautions similarly, saying that these exposures can irritate the airways, worsen inflammation, and aggravate conditions like asthma or COPD. He said, “For someone whose lungs have already been affected by smoking, repeated exposure can further compromise respiratory health.”

He advised that former smokers should avoid second-hand tobacco smoke, minimise exposure during periods of severe air pollution where practical and use appropriate protective equipment when occupational exposure to dust or fumes cannot be avoided.

He added, “Persistent cough, wheezing, breathlessness, recurrent chest infections, blood in sputum or an unexplained decline in exercise capacity should not be dismissed simply because a person has stopped smoking; these symptoms warrant medical evaluation.”

Conclusion

For someone who smoked occasionally or for a shorter period and stops before significant structural damage develops, there may be substantial recovery of airway function and symptoms. For a long-term heavy smoker, quitting can still produce important benefits, including slowing further loss of lung function and improving symptoms, but it cannot always return the lungs to their original state.

“The good news is that quitting smoking benefits the lungs at any age, regardless of how long or how heavily a person has smoked,” Dr Mehta said.

The lungs may not be able to erase every scar left by years of tobacco exposure, but stopping the exposure gives them the opportunity to recover where recovery is possible and, just as importantly, protects the lung function that has not yet been lost.

“Every smoke-free day means less exposure to the lungs and a better opportunity to preserve the lung function you still have,” Dr Mehta said.

A new study has revealed an alarming trend in stroke cases in the past three decades. Strokes have often been associated as an age-related disease. But according to a study published in Neurology, the rate of stroke among adults aged 20 to 54 has nearly doubled between 1993-94 and 2020.

Researchers examined data from the Greater Cincinnati and Northern Kentucky Stroke Study and identified 2,076 first-time strokes among people in this age group.

The rate of stroke rose from 33.9 cases per 100,000 person-years in 1993-94 to 62.2 in 2020. The increase was largely driven by ischemic stroke, which happens when a blood vessel in the brain becomes blocked.

The study points towards an alarming pattern, especially among younger age groups. It raises the question of why are strokes are occurring earlier in life?

High Blood Pressure, Diabetes And Other Risks

The researchers found that several risk factors of stroke became more common among younger people. These included lifestyle disorders like high blood pressure, diabetes and atrial fibrillation, an irregular heart rhythm that can increase the risk of blood clots.

Apart from lifestyle diseases, researchers also saw an increase in substance use. Among younger adults who had suffered a stroke, substance use rose from 4.6% in 1993-94 to 40.2% in 2020. Much of this increase was linked to marijuana use.

However, the study does not prove that these factors caused the overall rise in stroke rates. Researchers did not have comparable information from people who had not suffered a stroke, making it impossible to determine whether the changing risk factors directly explain the surge in cases.

According to the study, the increase was concentrated mainly in ischemic strokes. The rate of ischemic stroke among 20- to 54-year-olds rose from 23.8 to 47.3 cases per 100,000 person-years during the study period.

Researchers did not observe a similar increase in intracerebral haemorrhage, which involves bleeding within the brain, or subarachnoid haemorrhage, which involves bleeding around the brain.

Also read: Can A Roller Coaster Cause A Brain Bleed? What Sudden Acceleration And Deceleration Does To The Brain

What Is An Ischemic Stroke?

An ischemic stroke occurs when a blood vessel supplying part of the brain becomes blocked, cutting off oxygen and nutrients. Brain cells can start dying within minutes, which is why stroke treatment is highly time-sensitive.

The warning signs of stroke can appear suddenly. They include:

• Facial drooping
• Weakness
• Numbness in an arm or leg
• Difficulty speaking

The commonly used FAST acronym stands for Face, Arm, Speech and Time. If these symptoms appear, emergency medical care should be sought immediately.

Also read: UK Student Nearly Dies After Accidental Paracetamol Overdose: Why It Can Cause Liver Failure

More Young People Are Surviving Stroke

This is another interesting finding. Although stroke became more common among younger adults, the study found that the 30-day death rate declined modestly, from 11.7% in 1993-94 to 9.4% in 2020 after adjusting for age, race and sex.

That means more younger people may be surviving strokes but potentially living with their long-term consequences.

The researchers say the findings highlight the importance of identifying and managing stroke risk factors earlier in adulthood. More research is still required to understand what is behind the changing pattern and how it can be prevented.