Your body hosts trillions of bacteria, viruses, and fungi, collectively known as the microbiome. While some bacteria are linked to disease, many play essential roles in supporting your immune system, heart health, weight management, and overall well-being. This article delves into the significance of the gut microbiome and its impact on health.

What Is Gut Microbiome?

Interestingly, bacterial cells outnumber human cells in the body, with approximately 40 trillion bacterial cells compared to 30 trillion human cells. With up to 1,000 species of bacteria present in the gut, each plays a distinct role. While most bacteria contribute positively to health, some can be harmful. Together, these microbes weigh around 1–2 kilograms, functioning almost like an additional organ essential for overall well-being.

How Does Gut Microbiome Influence Your Health?

The relationship between humans and microbes has evolved over millions of years, with the gut microbiome playing a crucial role from birth. Initial exposure to microbes occurs during birth, and some evidence suggests that exposure begins in the womb. As the microbiome diversifies, it starts influencing key bodily functions:

Digestion of breast milk: Beneficial bacteria like Bifidobacteria help break down essential sugars in breast milk, supporting infant growth.

Fiber digestion: Some bacteria process fiber into short-chain fatty acids, which contribute to gut health and reduce risks of obesity, diabetes, and heart disease.

Immune system regulation: The gut microbiome interacts with immune cells, influencing how the body responds to infections.

Brain health: Emerging research suggests a link between the gut microbiome and brain function, potentially affecting mental health and neurological processes.

Gut Microbiome And Weight Management

An imbalance between beneficial and harmful microbes, known as gut dysbiosis, may contribute to weight gain. Studies on identical twins—one with obesity and the other without—suggest that microbiome composition plays a role in body weight independent of genetics. Additionally, animal studies indicate that gut bacteria can influence weight gain, even when calorie intake remains constant.

Probiotics, beneficial bacteria found in supplements and certain foods, can help restore gut balance and support weight loss, though their effects may be modest.

Gut Health And Disease Prevention

The gut microbiome plays a vital role in preventing and managing conditions like irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Imbalances in gut bacteria may lead to bloating, cramps, and digestive issues. On the other hand, beneficial bacteria like Bifidobacteria and Lactobacilli help strengthen the intestinal lining, reducing the risk of gut-related disorders.

Impact On Heart Health

Research suggests that the gut microbiome influences heart health by affecting cholesterol levels and blood pressure. Certain harmful bacteria produce trimethylamine N-oxide (TMAO), a compound linked to blocked arteries and heart disease. However, probiotics, particularly those containing Lactobacilli, may help reduce cholesterol levels and promote cardiovascular health.

Blood Sugar Regulation And Diabetes Risk

The gut microbiome also plays a role in regulating blood sugar levels. Research on infants genetically predisposed to type 1 diabetes indicates that gut microbiome diversity declines before disease onset. Furthermore, individual variations in gut bacteria may explain why people experience different blood sugar responses to the same foods.

Connection Between Gut And Brain

The gut is physically connected to the brain through nerves, and certain bacteria help produce neurotransmitters like serotonin, which influence mood and mental health. Studies indicate that people with mental health disorders often have different gut bacteria compared to those without such conditions. Additionally, some probiotics have shown promise in alleviating symptoms of depression and anxiety.

Tips For Healthier Gut Microbiome

Maintaining a balanced gut microbiome is crucial for overall health. Here are some strategies to support gut health:

• Eat a diverse range of foods: A varied diet rich in fiber, legumes, and fruits promotes microbial diversity.
• Consume fermented foods: Yogurt, kefir, and sauerkraut contain probiotics that enhance gut health.
• Limit artificial sweeteners: Some artificial sweeteners can encourage the growth of harmful bacteria.
• Include prebiotic foods: Bananas, oats, and asparagus contain fibers that nourish beneficial bacteria.
• Breastfeed infants when possible: Breastfeeding promotes a healthier gut microbiome in babies.
• Choose whole grains: Whole grains contain fiber and beneficial compounds that support digestive health.
• Opt for a plant-based diet: Vegetarian diets may reduce inflammation and support a healthier gut microbiome.
• Consume polyphenol-rich foods: Green tea, dark chocolate, and olive oil contain compounds that foster beneficial bacteria.
• Take probiotics if needed: Probiotic supplements can help restore gut balance after disruptions, such as antibiotic use.
• Use antibiotics cautiously: While antibiotics can be life-saving, overuse can harm beneficial gut bacteria.

The UK recorded its coldest autumn so far when the temperatures fell as low as -12.6C in Scotland. This was the lowest recorded in November from the last 15 years. The mercury also fell to -7.6C in Wales, -6C in Northern Ireland and -6.7C in England. Cold health alters have been issued in England. The UK Health Security Agency (UKHSA) has issued amber cold-health alerts for North West, North East, and Yorkshire and Humber, while other areas are under yellow alerts.

With this new developments, a Yorkshire dentists has pointed out that cold weather could, in fact, impact one's dental health.

Dr Abdul Dalghous, a dentist at Yorkshite Dental Suite said that chilly weather can trigger changes inside your mouth. Even if you have not notices them before, the change in weather and the temperature drop could negatively impact your dental health.

What Does The Doctor Say?

Sensitivity

The doctor says that there could be sudden sensitivity that one can feel when the weather is cold outside. "If you feel a sharp, almost electric twinge in your teeth when you breathe in icy air, it may be a sign that your enamel is under strain," explains the doctor.

Dr Dalghous explains that sudden cold exposure could make teeth contract quickly, irritating the nerves inside the tooth.

Teeth Ache

The cold weather can slightly weaken your immune system, making you more susceptible to illnesses such as colds. The doctor explains, "It’s very common for sinus pressure to feel like a toothache. This is due to your sinuses swelling and pressing on the roots of your upper teeth, often creating a dull, aching sensation. Many people mistake this for dental pain when the real culprit is winter congestion."

Dry Mouth

Another common experience during winters is having a dry mouth. This happens because cold air tends to be less humid and thus breathing it in through your mouth could lead to a drier mouth than usual. "Saliva acts as your mouth's natural defense system, so, when levels drop, your teeth become more vulnerable to sensitivity, plaque build-up and decay," the doctor notes.

Pain While Drinking Cold Beverages Or Eating Cold Food

Winter weather could further amplify the discomfort that is caused by cold food or drinks. "If a sip or bite of a chilled snack causes pain that lingers, it could point to underlying issues such as enamel erosion, cavities or exposed dentine that are becoming more noticeable in colder weather.”

Small Cracks Could Be More Noticeable

Teeth naturally expand and contract when exposed to temperature shifts, and winter tends to make these changes more intense. Over time, this added stress can lead to tiny hairline cracks in the enamel. You may not spot them, but you might feel rough spots, sudden sensitivity in one area, or small chips you never noticed before.

Dr Abdul adds: “To help ease these changes, we recommend breathing through your nose where possible and avoid biting into cold foods. When it comes to your oral hygiene ensure you’re brushing twice a day using toothpaste designed for sensitivity and flossing. Following these will help your teeth during this cold weather!”

Your adolescence lasts well up to your 30s. A new, "cool" study as Prof Tara Spires Jones, tells BBC, noted that the human brain does not follow a simple, steady path from birth to old age. Instead, it moves through five clear phases, each marked by a shift in how its networks connect and communicate. The study is conducted by the researchers from the University of Cambridge, who analyzed thousands of brain scans to track how neural connections strengthen, weaken, and reorganize over time.

This large study involved nearly 4,000 people between infancy and age 90 and has now mapped these transitions, offering new insights into why periods of life differ so much in terms of learning, behaviors, and vulnerability to mental health conditions.

Their work shows that the brain remains in an adolescent state far longer than earlier believed and reaches a peak of efficiency only in the early thirties. The findings, published in Nature Communications, highlight striking turning points at the ages of nine, 32, 66 and 83.

The Five Phases Of Brain

Childhood: Birth to Age Nine

The study showed that during childhood, the brain grown rapidly, however, it also begins trimming the vast numbers of synapses formed in early life. This is what helps the brain decide which pathways truly matter. However, this period is not very efficient. It resembles a child wandering without a fixed route, exploring freely rather than moving directly from one point to another. The purpose is exploration, not precision.

Adolescence: Age Nine to 32

A dramatic shift begins around age nine. The brain enters a long stretch of heightened efficiency as it reorganizes its neural networks with remarkable speed and intensity.

This is the phase where mental health vulnerabilities often emerge, since the brain is restructuring at an unusually rapid pace.

This part of the study also breaks the conventional idea that associated adolescence typically with the teenage years. Modern neuroscience suggests it extends into the twenties. This study pushes that boundary even further, indicating that the adolescent phase may last all the way to 32.

During this time, the brain reaches its most efficient point, and many cognitive abilities are thought to peak.

Adulthood: Age 32 to 66

After the long adolescent stretch, adulthood brings stability. The study shows that adulthood actually comes from the age 32, again a shift from what conventionally was believed adulthood to be. This is the brain’s most settled era, lasting more than three decades. Change continues, but at a gentler pace and in a more predictable pattern. The efficiency gained earlier begins to level out. Many people recognize this phase as a period when their cognitive strengths, personality and sense of self feel most consistent. The fireworks of earlier development give way to a steady rhythm.

Early Aging: Age 66 to 83

The period after 66 marks the beginning of early ageing. It does not arrive as a sudden decline. Instead, there are subtle shifts in how different parts of the brain coordinate.

Rather than functioning as one unified network, the brain begins to break into clusters of regions that work more closely within their own groups. It is similar to a band whose members start pursuing individual projects while still occasionally performing together.

Although the study focused on healthy brains, this is also the age when conditions linked to ageing, such as high blood pressure and dementia, begin to appear more frequently.

Late Aging: 83 And Beyond

The final phase begins at around 83. Data for this group was more limited, since it is harder to find older adults with no underlying health issues. Even so, the scans show that the patterns seen in early ageing become more pronounced. The brain’s networks continue to drift apart, and communication between regions becomes less synchronized.

As of 8.30 am, the pollution levels in New Delhi stood at the AQI of 293, according to aqi.in, which is equivalent to smoking 8.9 cigarettes per day, 62.3 cigarettes per week, and around 267 cigarettes per month, based on the average PM2.5 concentration over the last 24 hours.

While GRAP measures have been implemented in Delhi, there are still a section of people who continue to step out for work and other chores. From time and again experts, doctors, and researcher have pointed out the negative health impact the pollution bears on people. It is no longer limited to lungs or respiratory issues, but goes much beyond it. Ambient air pollution is responsible for fertility issues, bone health, and even cognitive risks like dementia, and more.

However, there is another health risk that people did not know can be impacted by pollution. It is your blood health or blood function.

What Is Blood Health?

Blood health refers to blood's ability to perform its vital functions, which includes transporting oxygen, nutrients, fighting infections, and regulating body temperature. Unhealthy blood could lead to disorders like anemia, blood clots, or even blood cancer.

How Does Air Pollution Impact Blood Health?

As per a 2024 study published in the journal BMC Public Health, titled Association of Ambient Air Pollution With Hemoglobin Levels and Anemia In The General Population of Korean Adults noted the detrimental effects of air pollution exposure on hemoglobin concentrations and anemia in specific populations, which included children, pregnant women, and the elderly.

The study noted that the pollutants in the air contributes to disturbances in iron homeostasis, thus the exposure to air pollution leads to cellular iron deficiency through the activation of oxidation production. It also increases secretion of pro-inflammatory mediators. This pro-inflammatory cytokines that are now increased cause a deficiency erythropoietin secretion, resulting in anemia.

In addition, exposure to air pollution increases the secretion of reactive oxygen species, resulting in oxidative stress. In 2008, an experimental study in a murine model reported that oxidative stress was closely related to iron deficiency anemia.

Another advisory from 2024, published in the National Institute of Health's (NIH) official website states that long term exposure to air pollution is linked to blood clots in veins that bring blood to the heart. The study was published by NIH, which included 6,651 US adults who were followed for an average 17 years between 2000 and 2018. Throughout the study, 284 adults developed blood clots in deep veins. Whereas 89% to a more than two-fold increases risk based on long term exposure was also noted for those who lived near polluted areas.

"Exposure to air pollution, which can set the stage for inflammation and contribute to blood clotting, has long been associated with cardiovascular and respiratory diseases. While previous research has also suggested a link to VTE, this is the largest, most comprehensive U.S. study to report that association with three different types of air pollutants," the advisory read.

The pollutants included particulate matter, which are tiny particles equal to or less than 2.5 micrometers, which can be inhaled easily, and can penetrated through every organ, and enter your blood streams.

Furthermore, pollutants like PM2.5 and PM10, benzene, polycyclic aromatic hydrocarbons and heavy metals like arsenic and lead could also be absorbed into the lungs and passed to blood streams. These trigger oxidative stress, DNA damage and inflammatory responses, all of which contribute to abnormal cell growth and mutations in blood cells. A comprehensive review published by the World Health Organization (WHO) suggested that this exposure could also increase the risk of blood cancer by 15 to 40% in people, depending on the exposure of pollution.