As the planet warms, the human body faces stresses beyond mere discomfort. We’ve long known that heat can sap energy, cause dehydration, and strain the cardiovascular system but a new study suggests that exposure to extreme heat may have an even more profound effect- accelerating biological aging, comparable to lifestyle risks like smoking or heavy drinking.

The findings, which was spearheaded by researchers at the University of Hong Kong and was published in Nature Climate Change, illuminates an often-unappreciated effect of climate change, discussing how the environment can change the very rate at which our bodies age.

Biological vs. Chronological Age

Most of us are familiar with chronological age—how many years we’ve been alive. Biological age, however, measures how well our tissues, organs, and cells are functioning. While two people may both be 50 years old chronologically, their biological ages could differ significantly based on genetics, lifestyle, and environmental exposures.

The research highlighted the fact that prolonged exposure to heat waves is the cause of this disparity, over time weakening organ systems, impacting blood pressure, cholesterol levels, liver and renal function, and finally elevating cardiovascular disease, diabetes, cancer, and dementia risks.

The researchers studied 24,922 Taiwanese residents who had medical checks between 2008 and 2022. By matching participants' medical histories with heat-wave frequencies at their registered residences, the authors could estimate how repeated exposure to high temperatures affected biological aging through the years.

Taiwan had approximately 30 heat waves over the study period, which were defined as multi-day hot-weather events. The volunteers were separated into four heat-wave exposure groups. Each increase in exposure was linked to an extra 0.023 to 0.031 years of biological age—proof that heat, much like smoking or drinking alcohol, can significantly influence the body's aging process.

Why Have Heat Waves Become A Major Public Health Concern?

Severe heat is not only unpleasant; it can have cumulative, long-term health effects. In a two-year period, repeated heat wave exposure was shown to increase an individual's biological age by eight to 12 days. On an individual basis, this might seem insignificant, but over populations and decades, the effect could be significant.

Older adults, laborers, and those living in rural areas are especially susceptible. These individuals encounter more heat exposure as a result of fewer cooling technologies, longer daylight hours spent outside, or job requirements, and thereby experience greater acceleration of biological aging compared to less exposed populations.

Why Heat Waves Harm Your Body Worse Than Smoking and Drinking?

The research points towards a wider intersection between lifestyle and environment. Biological aging, apart from temperature, is affected by diet, physical fitness, obesity, and socioeconomic status. Heat exposure will possibly enlarge the existing vulnerabilities, particularly in resource-poor communities.

Interestingly, however, the researchers noted a slight decrease in the heat-aging effect during the 15-year study. Although the reason is speculative, they propose greater use of cooling technologies such as air conditioning could reduce some of the effect—a reassuring indication that adaptation strategies can have a real impact.

Climate Change, Aging, and Global Health

By the year 2050, nearly 16 percent of the world's population will be 65 and older. The longer people live, the more vital the quality of those additional years is. Increased biological aging from environmental insults such as heat waves is a threat not just to personal health but to global public health systems.

Policy actions can be required in order to combat environmental inequalities, protect healthy aging, and minimize exposure to high temperatures. The research highlights the imperative for climate adaptation action: heat waves are not a nuisance; they are a silent force behind aging and increased risk of chronic disease.

Although heat-induced aging is not a sudden health emergency, in the larger scheme of health hazards, it is a cumulative, insidious one. The results of the study reaffirm that lifestyle factors such as abstention from smoking and excessive alcohol consumption—remain important, but exposure to the environment is equally so.

Knowledge about how heat waves interact with the body at a cellular level brings new possibilities for public health planning. For individuals, uncomplicated adaptation measures—drinking plenty of fluids, keeping outdoor activity to the coolest part of the day, and employing cooling technology can potentially counteract biological aging in a hotter world.

Climate change is expected to make extreme heat events more intensive and more common. Healthy aging will depend on safeguarding susceptible groups, improving access to cooling services, and incorporating environmental risk factors into public health interventions.

Thick smog blanketed India’s capital on Tuesday (October 21), a day after millions celebrated the Hindu festival of Diwali with fireworks that pushed air pollution to dangerous levels across the city. People in New Delhi kept bursting firecrackers late into Monday night, filling the air with smoke and fine particles. These mixed with the usual seasonal pollution and still weather conditions, creating a hazardous atmosphere.

By Tuesday morning, the city’s Air Quality Index had crossed 350 in several neighborhoods, classified as “severe” and unsafe to breathe according to the World Health Organization’s recommended daily exposure limits. With pollution levels this high, is it truly safe for senior citizens, or anyone, to go for their usual morning walks?

Delhi Air Quality Reaches ‘Severe Category’

Air pollution occurs when harmful substances like particulate matter (PM2.5 and PM10), carbon monoxide, nitrogen oxides, and other toxic gases contaminate the air, affecting both health and the environment. After Diwali, pollution often spikes due to widespread firecracker use, which releases large amounts of smoke and fine toxic particles. Cooler temperatures and low wind during this season trap these pollutants near the ground, forming thick smog. This makes outdoor activities, such as walking, risky, especially for those with respiratory issues, allergies, or heart conditions.

Data shows that the average AQI hit 451 early on October 21, 1.8 times above the national average as pollution soared after the festive celebrations. Later, the city’s AQI improved slightly to 352 by 9 am, falling into the ‘very poor’ category, according to the Central Pollution Control Bureau (CPCB). Several areas were still in the red zone, with readings like Wazirpur (435), Dwarka (422), Ashok Vihar (445), and Anand Vihar (440), all recording ‘severe’ pollution levels.

Should You Go For Morning Walks After Diwali Week Amid High Air Pollution?

Health experts strongly advise against going for morning walks in the week following Diwali, as air pollution tends to peak during this period. Staying indoors is the safest option to protect your health from toxic particles. Instead, exercise inside your home, postpone outdoor walks until air quality improves, and wear an N95 mask if you must step out for short periods.

Morning walks in heavily polluted air are particularly risky, as cooler temperatures and low wind trap pollutants near the ground. Walking in such conditions increases inhalation of PM2.5 and PM10, as well as harmful gases, which can irritate the lungs, worsen asthma, trigger shortness of breath, and raise the risk of long-term heart and lung problems. Children, older adults, and anyone with pre-existing health conditions are especially vulnerable.

How Does Exposure To Severe AQI Affect Your Lungs And Heart?

Dr. Manav Manchanda, Director of Respiratory Critical Care & Sleep Medicine at Asian Hospital, explains that fine air pollution particles (PM2.5 and PM10) bypass the nose and throat, reaching deep into the lungs. This can cause inflammation, excess mucus, chest tightness, and coughing, even in healthy individuals. People with asthma or allergies may experience worsened symptoms, while others may notice shortness of breath or reduced lung capacity after outdoor activity.

Air pollution also affects the heart, triggering inflammation in blood vessels, raising blood pressure, and causing palpitations. Dr Manchanda said, "Even short-term exposure to high AQI can increase the risk of heart attacks and strokes in vulnerable individuals. Watch for early signs like dry cough, sore throat, eye irritation, fatigue, or unusual chest discomfort, as these indicate the body reacting to toxic air."

Tips To Stay Safe After Inhaling ‘Severe’ Air Pollution

Living in severe air pollution can make you feel breathless or create a heavy sensation in your chest. You may also experience persistent allergies such as colds, constant sneezing, or coughing. Air pollution can even affect mental health, weaken immunity, and make you more prone to fever. To protect yourself:

Check which areas have better air quality, whether indoors or outdoors. Use an AQI app or monitor for outdoor levels, and an indoor air quality monitor for home safety. Your lungs need breaks from constant exposure to dust and pollutants.

Drink plenty of fluids: Staying hydrated is crucial after breathing polluted air. You can also sip natural teas like green tea, turmeric, or ginger water, which are rich in antioxidants. Research from the NIH suggests water can help reduce inflammation caused by pollution.

Keep yourself clean and comfortable: Fine dust clings to your clothes and hair, prolonging exposure. Take a shower as soon as possible, change into fresh clothes, and try breathing exercises. You can also use a saline spray to cleanse your nasal passages.

Monitor your symptoms: Rest and watch for heaviness in the chest, continuous coughing, runny nose, headaches, chest pain, or difficulty breathing. These could signal health effects from pollution exposure.

Don’t ignore warning signs: If you notice any of the above symptoms, consult a doctor immediately. Early attention can prevent serious health complications. Explain your symptoms fully to receive appropriate treatment.

Diseases do not always have linear symptoms. For example, if you have heart problems, then the symptoms may not always be chest pain; it could also show up in different ways. This shows how interconnected our organs are, one organ lacking, could burden the other causing problems. Similarly, did you know there is a disease that affects not just your heart, but also your kidney and digestive health? This disease is much more common than you think, however, a new survey showed that most people do not know about it.

A recent survey by the American Heart Association (AHA) found a huge gap in health knowledge: a staggering 9 out of 10 American adults have never heard of Cardiovascular-Kidney-Metabolic (CKM) syndrome. This lack of awareness is a major problem because the condition is so widespread; it affects or puts at risk nearly 90% of all adults.

CKM syndrome is a relatively new term used to describe the coexistence of several serious health problems at the same time: heart disease, kidney disease, diabetes, and obesity. The AHA defined it to make people realize that these conditions don't happen in isolation; they are deeply connected. Even though few people know the name CKM syndrome, the survey did find an upside: most people who learned about it were very interested in getting more information.

What is CKM and Who Is At Risk?

CKM syndrome is all about the dangerous link between three essential body parts: the heart (cardiovascular system), the kidneys, and the metabolic system. The metabolic system is like your body energy factory; it handles how you create, use, and store energy, which directly influences your weight and blood sugar levels. When one of these systems starts to fail, it often puts extra strain on the others, creating a vicious cycle that quickly makes all the conditions worse.

A 2024 study published in JAMA found that the following are common risk factors for CKM syndrome, and nearly 90% of Americans have at least one:

• High blood pressure
• Abnormal cholesterol
• High blood sugar
• Excess weight
• Reduced kidney function

The key message is that having several of these risk factors together is much more dangerous than having just one. It greatly increases your chances of having a life-threatening event like a heart attack or stroke. The good news is that CKM syndrome isn't set in stone; for most people, it can be reversed or significantly improved by changing what they eat, increasing physical activity, and getting the right medical care.

Do People Know What Cardiovascular-Kidney-Metabolic Syndrome Is?

The AHA survey, which collected responses from about 4,000 U.S. adults in 2025, made it clear that a public education effort is urgently needed. The main results showed low awareness but high interest:

• 12% had heard about CKM syndrome
• 72% were interested in learning more
• 79% though it was important to understand CKM

The survey also uncovered some dangerous misconceptions about managing health:

• 68% of adults incorrectly believe that the best way to handle heart, kidney, and metabolic conditions is to treat them one at a time, or they simply don't know the best approach.
• 42% of adults either doubt or are unsure that a healthy heart could actually be damaged by problems in other organ systems.

AHA Chief Medical Officer Dr. Eduardo Sanchez stressed that since these body systems are so interconnected, they must be treated in a coordinated way by healthcare providers.

How Can We Prevent CKM Syndrome?

The American Heart Association (AHA) knows that almost no one has heard of CKM syndrome, so they are starting a major effort called the CKM Health Initiative.

The main goal is simple, to teach the public how the heart, kidneys, and metabolism are all connected. By showing people these links, the AHA hopes to encourage everyone to act early to prevent major health issues like heart attacks and heart failure.

Teaching the Public

The AHA is making easy-to-read materials and launching a website to clearly explain the connections. They are stressing that everyone needs to get regular check-ups for important health numbers like blood pressure, cholesterol, weight, blood sugar, and kidney function.

Training Doctors

The AHA is working directly with doctors and healthcare teams across the country. The goal is to get doctors who treat different conditions to work together better so they can provide coordinated care for patients who have multiple health problems.

In addition to this, the AHA is taking a major leadership step. They are preparing to release the first-ever official clinical guidelines for CKM syndrome in early 2026. These guidelines will give doctors a clear, tested set of rules for how to best diagnose and treat the condition.

Smell is a sense that helps us navigate, feel, and in fact remember things. Thanks or not, but Covid-19 also helped us know its importance, when many people lost the sense of their smell, as one of the major COVID-19 symptom. But, that is not just it, in a podcast posted on Instagram Dr Sanjay Bhojraj, board-certified interventional cardiologist talked to Dr Michael Leon, PhD Professor Emeritus of Neurobiology and Behavior at the Charlie Dunlop School of Biological Sciences on surprising link between smell and overall well-being.

Can Smell Predict How Long Will You Live?

“By the time you reach middle age, your sense of smell can actually predict all-cause mortality,” says Dr Leon. “That means whether you live or die, for any reason, can be accurately reflected in your ability to detect odors.”

The expert says that out olfactory system bears a direct impact to the brain's memory and emotional centers. “It has a great deal of impact when you lose it. And also when you amplify it. When you smell a pleasant odor, it activates the cerebellum and increases sniffing. For example, when you smell a rose, you naturally take a deep sniff.”

How Does Smell Impact Your Brain?

When you encounter a bad or disgusting odor, your body reflexively stops respiration. You instinctively avoid breathing it in,” Dr Leon says.

The expert said it is these subtle responses that influence one's memories, emotions, and overall brain function. “The olfactory system is just much more powerful than most people realize,” he says.

Can Body Odor Also Reveal Things About Your Health?

This link between smell and health became famous when Joy Milne, a retired Scottish nurse, claimed she could detect Parkinson’s disease by scent alone. Years before her husband’s diagnosis, she noticed a distinct musky odor on him. When she later met others with Parkinson’s, they all carried the same smell. Curious scientists put her to the test — and she correctly identified patients just by sniffing their shirts, even predicting one man’s diagnosis a year before doctors confirmed it.

Her unique ability led researchers like Professor Perdita Barran at the University of Manchester to discover that people with Parkinson’s excrete specific lipid-like molecules through their skin. These include hippuric acid and octadecanal, which may form the disease’s distinct odor. Barran’s team is now developing a simple skin-swab test that could help doctors detect Parkinson’s much earlier.

Different diseases create different odors. For example, a fruity or “rotten apple” smell can indicate uncontrolled diabetes, caused by a build-up of ketones. A fishy or ammonia-like scent might suggest kidney problems, while a musty smell could point to liver disease. Even infections leave olfactory traces — cholera, tuberculosis, and C. difficile each produce distinct, unpleasant aromas.