As per the World Health Organization, all but 1% of the world's population is exposed to unhealthy air and also exceeds the WHO limits for pollutants. However, there are some parts of the world where aur quality has improved through policies that limits pollution, while in other parts, it has not reached the desired results.

For US, more than 25% of the population is exposed to "unhealthy" air as per the Environmental Protection Agency (EPA), this is according to the report by the climate non-profit First Street Foundation. By 2050, the number of people exposed to "unhealthy" air will increase by more than half. The worst days of air pollution, reports BBC, "hazardous" or maroon under the EPA's system will rise by 27%.

Why are we talking about this today? It is because of the recent wildfire in California, which started on January 7. This is also one of the factors that is spiking the PM2.5 levels. It has increased by up to five micrograms per cubic metre in the western US in the past decade.

What is PM2.5?

It is a type of air pollution which is made of particulate matter and measures 2.5 micrometres across or less. It is roughly 30 times smaller than the width of a human hair. These particles are made with a mixture of solid and liquid substances, which varies in their chemical composition, including carbon, metals, and organic compounds.

These specks of airborne soot, dust and other substances can also trigger inflammation, which could also damage your brain.

As per a 2021 study titled The Changing risk and burden of wildfire in the United States, a quarter of US's PM2.5 pollution was caused by wildfire smoke. In 2023, US also witnessed a significant dip in air quality and visibility as smoke from wildfires north of the Canadian border entered across the continent. In May 2024, Canada also saw a start to its wildfire season, and one town was evacuated in British Colombia.

Wildfire smoke and its effects

Wildfires do not only affect those who live near forests, peatlands, and grasslands, but also to the cities and environment in general. It can send plumes up to 14 miles or 23km into the stratosphere, and from there, it can spread all over the globe. For instance, in 2023, the Siberian wildfires released smoke that travelled across the Pacific Oceans to reach Alaska and Seattle.

Other than PM2.5, wildfire smoke is also harmful to immune cells in lungs, and the toxicity could be four times greater than particulates from other types of pollution.

Another 2019 study titled Effects of Atmosphere Processing on the Oxidative Potential of Biomass Burning Organic Aerosols found the toxicity of smoke doubled in the hours after it was first emitted and reached four times greater toxicity at its peak.

Health Impact

There have been research that shows how pollution affects your brain. It can lead to impaired judgment, poorer performance in school and even higher levels of crime, as per the 2018 study by the London School of Economics.

Other health concerns include weight gain. There have been researches that links airborne pollution such as PM2.5 to obesity. The studies have found that children who live in most polluted areas are twice as more likely to have obesity. Some studies also find the link of air pollution harming our sense of smell. As per an Italian study from 2022, titled Association between environmental air pollution and olfactory functioning among Italian adolescents and young adults in Northern Italy, noses of teenagers and young adults became less sensitive to odors after being exposed to nitrogen dioxide, which is a component in traffic fumes.

Seeing your child suddenly screaming at night, with wide eyes and thrashing limbs, can be deeply unsettling. However, remaining calm and focusing on safety is crucial for parents during the sleep terror episodes, said health experts.

Sleep terrors, also known as night terrors, are episodes of sudden fear, screaming, or intense distress that occur during sleep.

The condition is more common in children, especially between the ages of 3 and 8 years, as their sleep patterns are still maturing.

Unlike nightmares, which usually happen during dreaming (REM sleep) and are often remembered, sleep terrors occur during deep non-REM sleep.

Dr Preeti Singh, Senior Consultant, Clinical Psychology, Max Super Speciality Hospital, Dwarka told HealthandMe, that while it may be frightening to witness, especially for parents, sleep terrors themselves are usually not harmful.

Although most kids outgrow this naturally, if the episodes are violent or very frequent, consult a specialist, added Dr Sudhir Kumar, a neurologist at Apollo Hospitals, Hyderabad.

What Are Sleep Terrors

During sleep terror, the child may sit up abruptly, shout, appear frightened, sweat, breathe rapidly, and be difficult to console. In most cases, they do not recall the episode the next morning.

Sleep terrors typically occur in the first third of the night, during deep sleep (slow-wave sleep). They are considered a type of parasomnia, meaning an unusual behavior during sleep.

Dr Kumar, in a post on social media platform X, explained that unlike a bad dream, a sleep terror happens in deep sleep (Stage N3).

It is characterized by abrupt sitting up/screaming, with physical signs that include a fast heart rate, sweating, and dilated pupils.

"It is 11 PM. Your child suddenly sits up, screams at the top of their lungs, and looks terrified. They are not responding to you, and they seem to be looking right through you. This is likely a sleep terror (night terror), a common NREM sleep parasomnia in children aged 3-12,” said Dr Kumar, popularly known as the Hyderabad doctor, on X.

The expert noted that the children are unlikely to recognize the parents and be "consoled" during the episodes.

What Factors Trigger Sleep Terrors

• Sleep deprivation or irregular sleep schedules
• Fever or illness
• Emotional stress or anxiety
• Major life changes or trauma
• Family history of parasomnias
• Certain medications

For children, sleep terrors are often developmental and tend to reduce as the nervous system matures, Dr Singh told HealthanMe.

How Can Parents Respond?

Parents often feel alarmed during a sleep terror episode, but the key is to remain calm, the experts said. They said during an episode:

• Do not try to fully wake the child, as this may increase confusion and agitation.
• Gently ensure the child is safe and cannot injure themselves.
• Speak softly and reassuringly, even if they do not respond.
• Wait for the episode to pass, which usually happens within a few minutes.

Other preventive measures include:

• Maintaining a consistent bedtime routine
• Ensuring the child gets adequate sleep
• Reducing screen time before bed
• Managing stress during the day
• Creating a calm and secure sleep environment

How To Manage

Most children do not require medical treatment, as sleep terrors usually resolve on their own with age. Treatment is considered when episodes are frequent, severe, cause injury, or significantly disrupt family life.

However, addressing sleep deprivation, treating any underlying medical conditions (e.g., sleep apnea), counseling or stress management strategies can help.

Hypertension or high blood pressure, a major risk for stroke, is preventable and treatable. Yet it accounts for about 14 per cent of cases of stroke among young adults aged below 45 years.

High blood pressure can be defined as the increasing pressure in blood vessels marked as 140/90 mmHg or higher.

Uncontrolled hypertension can burst or block arteries that supply blood and oxygen to the brain, causing a stroke.

A recent study by the Indian Council of Medical Research (ICMR) found that hypertension (74.5 percent) was the most common risk factor for stroke and related deaths (27.8 percent) and significant disability (about 30 per cent) across India.

“Blood vessel walls can be damaged through uncontrolled high blood pressure, making them prone to blockage or rupture. The good news is that hypertension is preventable through regular monitoring, reduced intake of salt, exercise stress control, and medication when required,” Dr. Rajul Aggarwal, Director - Neurology, Sri Balaji Action Medical Institute, Delhi, told HealthandMe.

How Does Hypertension Increase The Risk Of Stroke?

Chronic high pressure forces the brain to compensate, leading to vessel remodeling, narrowing, and eventually rupture or clotting.

The ICMR study reported that ischemic stroke accounted for 60 percent of cases.

The experts explained that in the case of ischemic stroke, high blood pressure damages artery walls, fostering plaque buildup (atherosclerosis) or allowing clots to form and block blood flow to the brain.

On the other hand, with hemorrhagic Stroke, constant strain caused by high blood pressure weakens artery walls, causing them to burst or leak blood into the brain. This can result in severe damage or life-threatening emergencies.

“When blood pressure stays high for years, it slowly strains the blood vessels -- nothing dramatic at first, which is why people ignore it. The arteries become stiff and fragile, sometimes narrowing, sometimes tearing,” Dr. Gunjan Shah, Interventional Cardiologist, Narayana Hospital, Ahmedabad, told HealthandMe.

"This makes clots or bleeding in the brain more likely, leading to ischemic or hemorrhagic stroke, even in people who otherwise feel perfectly fit and busy with daily life," Dr. Shah added.

Importance of the ‘Golden Hour’ In Stroke Care

In stroke-related cases, the golden hour -- referred to as the critical first 60 minutes after symptom onset -- is very much critical. Early medical treatment during the window can prevent death risk as well as boost health outcomes.

However, the ICMR study, published in the International Journal of Stroke, showed that just 20 percent of patients arrived in the hospital after 24 hours of the onset of symptoms.

Dr. Aggarwal said treatment within the first 60 minutes can significantly reduce the brain damage and improve survival as well.

“In a stroke, time moves very differently. Brain cells begin getting damaged within minutes when blood flow stops. If someone reaches the hospital quickly -- within the golden hour -- we have a real chance to restore circulation and limit disability. Recognising symptoms early and not waiting at home can truly change how well a person recovers,” added Dr Shah.

How Can Hypertension And Stroke Be Prevented?

Hypertension is a modifiable disease, and the risks can be reduced by:

• Cutting down and managing stress
• Checking blood pressure regularly
• Treating high blood pressure
• Eating less salt
• Staying active
• Managing stress
• Sleeping properly
• Avoiding tobacco

Dr Shah said that many young patients delay care because they feel fine, but taking medicines on time and correcting lifestyle early can prevent serious problems later.

Living in the mountains has long been linked with a surprising health advantage. People who reside at high elevations appear less likely to develop diabetes than those living at sea level. For years, researchers observed this pattern but could not clearly explain why it happens.

Now, scientists say they finally have an answer. According to inputs and direct quotes shared with news agency ANI, low oxygen conditions trigger a unique change inside red blood cells that helps lower blood sugar levels.

How thin air changes the body

At high altitude, oxygen levels are lower than usual. To cope with this shortage, the human body adapts in several ways, including producing more red blood cells.

Researchers at the Gladstone Institutes found that these red blood cells do far more than simply transport oxygen. In low oxygen environments, they begin absorbing unusually large amounts of glucose from the bloodstream.

In simple terms, the cells start behaving like sugar sponges. By pulling glucose out of circulation, they naturally reduce blood sugar levels, which may explain why diabetes occurs less frequently in people living at higher elevations.

Senior author Isha Jain explained the significance of the finding in comments to ANI: “Red blood cells represent a hidden compartment of glucose metabolism that has not been appreciated until now. This discovery could open up entirely new ways to think about controlling blood sugar.”

The surprising glucose sink

The discovery emerged from experiments on mice exposed to hypoxia, the scientific term for reduced oxygen levels in the blood. The animals showed a rapid drop in blood glucose after eating, something usually associated with a lower risk of diabetes.

But scientists initially could not find where the sugar was going. They examined major organs such as the liver, brain and muscles but none accounted for the sudden disappearance of glucose.

First author Yolanda Marti Mateos told ANI: “When we gave sugar to the mice in hypoxia, it disappeared from their bloodstream almost instantly. We looked at muscle, brain, liver, all the usual suspects, but nothing in these organs could explain what was happening.”

Using advanced imaging techniques, the team discovered the missing destination. Red blood cells themselves were absorbing and using the glucose.

This was unexpected because red blood cells have traditionally been viewed as passive oxygen carriers rather than active metabolic regulators.

Further experiments showed that not only did the body produce more red blood cells in low oxygen conditions, but each individual cell also consumed more glucose than normal.

Research collaborator Angelo D’Alessandro said, “Red blood cells are usually thought of as passive oxygen carriers. Yet, we found that they can account for a substantial fraction of whole body glucose consumption, especially under hypoxia.”

Why this helps survival in low oxygen

The glucose absorbed by red blood cells is not wasted. Instead, it helps generate molecules that improve oxygen delivery to tissues.

This adaptation becomes crucial when oxygen is scarce. The body simultaneously improves oxygen distribution and reduces circulating sugar levels, a combination that may protect against diabetes.

A possible future treatment

The team also tested a new experimental drug called HypoxyStat that recreates the effects of low oxygen exposure. The pill works by making hemoglobin hold onto oxygen more tightly, mimicking high altitude conditions inside the body.

In diabetic mice, the treatment reversed high blood sugar and performed better than existing therapies.

Jain told ANI, “It opens the door to thinking about diabetes treatment in a fundamentally different way by recruiting red blood cells as glucose sinks.”

Researchers also noted the benefits lasted weeks after animals returned to normal oxygen conditions.

What this could mean beyond diabetes

Scientists believe the findings could influence other fields such as exercise science and trauma medicine, where oxygen supply and energy use are closely linked.

For now, the study provides a long sought explanation for the protective effect seen in mountain populations and suggests that future therapies may not target insulin or organs alone but the blood itself.

As Jain concluded in remarks shared with ANI, “This is just the beginning. There’s still so much to learn about how the whole body adapts to changes in oxygen and how we could leverage these mechanisms to treat a range of conditions.”