Air Pollution 2025- If You Are Breathing This Air, You Need to Read This Today!
- Ryan Fernando
- Nov 20
- 5 min read
Every year, we see a rise in AQI across India, but this time the situation has crossed a level that even I did not expect. Delhi touching 400+ AQI is not just a seasonal spike, it is a public health emergency. And it’s not just Delhi. Many Indian states are now experiencing dangerously polluted air, affecting millions of people who don’t even know what is happening to their bodies or what they should be doing about it. Some are parents wondering if their child’s persistent cough is “normal.” Others are young working professionals who feel breathless during their morning commute. Many simply want to understand what these AQI numbers really mean, and whether they should be worried.
As a nutritionist who works with families across India, I’ve seen how silently, and consistently, air pollution shapes human health. You may not feel it immediately, but the biological effects start long before symptoms become visible. And unless we understand what exactly AQI represents, we can’t protect ourselves effectively.
This blog is not a list of remedies, this is the science and the truth behind what is happening inside your body every time the AQI rises.
What AQI Actually Measures And Why It Matters More Than You Think?
AQI (Air Quality Index) is not just a number on a screen. It is a summary of how polluted the air is and how quickly that air can harm your lungs, heart, and brain. It measures a mix of pollutants, but the most dangerous one, and the one you hear the most about, is PM2.5.
What are PM2.5 particles?
They are ultrafine particles that are 30 times smaller than a strand of hair. Because they’re so tiny, they don’t stop at the nose or throat. They slip into the lungs, cross into the bloodstream, and travel to critical organs.
Scientific literature calls PM2.5 a “silent systemic toxin” because it affects:
Lung tissue
Blood vessels
Brain cells
Immune responses
Hormone balance
Cardiovascular stability
Once these particles enter circulation, they are extremely difficult for the body to remove.
This is why AQI above 200 is not just “bad weather.” It’s a medical concern.
Why Air Pollution Is Worse in Northern India?
People often assume smog is just “because of winter” or “stubble burning,” but the problem is layered and structural.
Here’s what contributes to chronic high AQI levels:
1. Geographical Bowl Effect - Cities like Delhi sit in a low-lying region surrounded by terrain that traps pollutants. During winter, this creates a lid-like effect, preventing air dispersion.
2. Temperature Inversion - Cold air settles at the surface while warm air stays above it. Pollutants get locked into the lower layer, the air we breathe.
3. Industrial + Vehicular Emission Density - One of the highest in the country, per square kilometre.
4. Seasonal Agricultural Burning - Smoke from crop residue travels hundreds of kilometres and mixes with local emissions.
5. Dust Load - Northern India has naturally high dust content, amplified by construction and dry weather.
When all these factors collide, the air becomes a chemical soup.
What Actually Happens Inside the Human Body on a High AQI Day?
Whether you are a child, working adult, or elderly individual, pollution affects all physiological systems, but some bodies are more vulnerable. Over the years, I’ve worked with athletes, children, chronic disease patients, and healthy young adults, and the pattern remains the same: the body struggles on polluted days even if the symptoms are invisible.
Here’s a breakdown of the physiological chain reaction.
1. The Airway Takes the First Hit
The moment polluted air touches the respiratory tract:
The airway lining becomes inflamed
Mucus production increases
Cilia (the tiny hair-like cleaners in your airway) slow down
Breathing becomes less efficient
Even if you don’t cough or sneeze, inflammation has already begun.
Children experience this much faster because their airways are narrower and immune systems still developing.
2. The Lungs Begin a Silent Stress Response
When PM2.5 and NO₂ enter the lower lungs:
Gas exchange becomes less efficient
Oxygen saturation may drop slightly
Free radicals increase dramatically
Your body responds with a burst of oxidative stress, something similar to what happens during heavy smoking.
Long-term exposure to polluted air is associated with:
Decline in lung function
Increased asthma risk
Chronic bronchial inflammation
Higher susceptibility to respiratory infections
Pollution does not just irritate the lungs. It rewires them.
3. Pollutants Enter the Bloodstream And the Impact Becomes Systemic
Once inside the blood, PM2.5 particles behave like microscopic intruders. They travel to organs, latch onto tissues, and trigger inflammatory reactions.
This contributes to:
Higher blood pressure
Thickening of blood vessels
Reduced insulin sensitivity
Greater oxidative damage
For people with diabetes, thyroid issues, autoimmunity, or PCOS, pollution can worsen symptoms by adding another layer of inflammation.
4. Pollution Impacts the Brain More Than Most People Realise
Neuroscience tells us that now PM2.5 particles can cross the blood-brain barrier, something that previously was believed to be nearly impossible.
Once inside the brain, they:
Increase neuroinflammation
Affect cognitive speed
Disrupt neurotransmitters
Exacerbate anxiety and mood fluctuations
This is why many parents report that their children feel irritable or fatigued during high-AQI weeks.
5. The Immune System Gets Overworked
Your immune system responds to polluted air exactly the way it responds to an infection, by activating inflammatory pathways.
But since pollution is ongoing, the immune system stays in a constant low-grade “alert mode.”
This contributes to:
Lower resistance to viral infections
Slower recovery
Increased allergic responses
Higher oxidative burden
It’s one reason why winter colds feel longer and more stubborn in high-pollution regions.
6. Pollution Worsens Gut Inflammation
It may sound unrelated, but air pollution alters gut microbiota.
PM2.5 exposure has been linked to:
Increased intestinal permeability (“leaky gut”)
Higher gut inflammation
Microbiome imbalance
When the gut becomes inflamed, nutrient absorption drops, something I frequently see in lab reports of clients from high-AQI areas.
Children and Elderly: The Two Most Affected Groups
In my work with families, two groups consistently show faster and stronger symptoms on high-pollution days:
Children
Higher breathing rate
Immature detox systems
Narrower airways
Developing immune response
This makes pollutant absorption faster and damage more intense.
Elderly Adults
Lower lung capacity
Higher oxidative stress
Coexisting heart or metabolic conditions
Slower immune response
Even brief exposure can trigger breathlessness, blood pressure spikes, or fatigue.
Every year when AQI rises, people search for quick tips, masks, teas, purifiers. And while those tools matter, understanding the biology is even more important.
Because once you understand what pollution does to your cells, you no longer treat it as “just smog.”
You see it for what it is:
A year-round health threat that needs both awareness and strategy.
I’ve created a dedicated PDF with structured, easy-to-apply steps you can start immediately. You can access it below:
And here’s the video where I break down the fundamentals of pollution and lung protection in detail. I’ve linked it here because many readers ask for additional explanation once they finish reading:
Cities like Delhi may not change overnight. The policies may take time. Weather patterns aren’t in our control. But what is in our control is how well-informed and prepared we are.
Air pollution is not just an environmental problem. It is a metabolic, respiratory, neurological, and immunological problem. And education is your first defence.
If you need help managing your diet and want to understand exactly what to eat to protect your health this winter—especially with rising air pollution, click the link below.