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.

After the social media trend of ‘ferritin face’ had everyone scrutinising their face for pale skin, dark circles and sluggish features due to low iron levels, attention is now shifting to hair. Described as ‘ferritin hair’, social media users have been attributing symptoms like unusual hair shedding, thinning and brittle strands to the body’s low iron stores.

The trend is not just a fluke. There is a medical basis for recognising iron deficiency in people facing hair loss. However, ‘ferritin hair’ is not a formal medical diagnosis. Hair loss can be due to several reasons, including hormonal changes, stress, thyroid disorders, nutritional deficiencies and genetic hair-loss conditions.

So is there a connection between ferritin and hair health and which signs should prompt someone to seek medical advice?

What Is Ferritin And How Is It Connected To Your Hair?

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Ferritin is a protein that stores iron in the body and releases it when needed. A blood ferritin test helps assess the body's iron reserves. Iron is essential for several functions, including the production of haemoglobin, which carries oxygen in the blood.

When iron stores are exhausted, the body prioritises essential functions over those that are not absolutely necessary for survival. Hair growth may be affected in some people, contributing to increased shedding.

A 2023 clinical review published in Cutis noted that measuring serum ferritin can be useful while evaluating people with diffuse hair loss, especially to identify underlying iron deficiency.

A 2026 study published in Cureus reported that low serum ferritin and telogen effluvium in women may be connected.

A separate systematic review published in 2026 also found lower ferritin levels among people with telogen effluvium.

The European Food Safety Authority has also observed a cause-and-effect relationship between iron intake and the maintenance of normal hair growth.

Possible Signs Of 'Ferritin Hair'

Also read: Ditching Dairy For Oat, Almond Milk? Your Body Could Miss Out On These 4 Essential Nutrients

Hair shedding: One possible sign is diffuse hair shedding, in which more hair than usual falls from across the scalp rather than from one specific area. This can occur due to a condition called telogen effluvium, in which more hair follicles than usual enter the resting phase of the hair-growth cycle.

Hair thinning: Constant shedding can make the hair appear less dense over time. Some people may notice a wider-looking parting or thinner volume.

Dry or brittle hair: Iron deficiency may cause dry, brittle hair. However, hair texture can also be affected by heat styling, chemical treatments and other nutritional factors.

Other symptoms: Hair shedding may occur with other signs of iron deficiency like fatigue, weakness, poor concentration, breathlessness, palpitations or pale skin.

Causes Of Iron Deficiency Or Low Ferritin Levels

Iron deficiency can develop when the body loses more iron than it absorbs and does not receive enough through diet. Heavy menstrual bleeding and pregnancy are common reasons for iron deficiency. Other possible causes include:

• Inadequate dietary iron: People who do not consume enough iron-rich foods are at risk if their diets are restrictive.
• Poor absorption: Conditions such as coeliac disease can interfere with the absorption of iron.
• Blood loss: Gastrointestinal conditions like gastritis and intestinal polyps can sometimes lead to iron loss.
• Increased requirements: Pregnancy can demand increased iron needs.

Delhi’s air pollution has worsened even before the onset of peak winter. This has raised concerns about development and health of children who are constantly exposed to high levels of fine particulate matter (PM2.5).

While the immediate effects of polluted air like coughing, wheezing and breathing difficulties are known, research says that long-term exposure can also impact children’s developing brains, including effects on their memory, attention, IQ and ability to learn.

Delhi Winter Pollution Highest In 3 Years

On November 12, Delhi's air quality got listed under 'very poor' category. Stations like IIT Delhi and Delhi IITM recorded an AQI of 416, while NSUT Jaffarpur and Delhi DPCC recorded 404. Anand Vihar station recorded 319 while DTU Delhi stated 372.

A new analysis by the Centre for Science and Environment (CSE), released recently, found that Delhi’s average PM2.5 concentration during the week preceding Diwali stood at 236 micrograms per cubic metre (µg/m³), the highest in the last three years. This was 97% higher than the 120 µg/m³ recorded in 2025 and 32% above the 179 µg/m³ recorded in 2024.

The analysis also found that pollution levels during the early winter period were higher this year than in 2025. Vehicular emissions and pollution from neighbouring NCR districts were among the major contributors. The findings suggest that firecracker smoke from Diwali aggravated an already high pollution burden.

Delhi’s pollution crisis is not only threatening people’s lungs and cardiovascular health, it is also posing significant risks to children’s brain health. Could breathing polluted air affect how well children concentrate, recall information and learn at school?

Also read: World Pneumonia Day 2026: Post-Diwali Cough Or Pneumonia? Doctors Explain Warning Signs

Effects Of PM2.5 On Children’s Cognitive Health

PM2.5 refers to fine particulate matter with a diameter of 2.5 micrometres or smaller. These particles are small enough to travel deep into the respiratory system, fueling inflammation and oxidative stress. Not just lungs, their effects may reach children’s nervous systems.

Dr Sushil Singla, Director, Paediatrics, Sarvodaya Hospital, Sector 8, Faridabad told HealthandMe, “Exposure to PM2.5 (fine particulate matter) can affect children's cognitive development, including memory, attention span and learning abilities. These tiny particles can penetrate deep into the lungs and may trigger inflammation and oxidative stress, which can have wider effects on the developing brain. Children are particularly vulnerable because their brains are still developing and they inhale more air relative to their body weight than adults.”

The developing brain goes through significant changes throughout childhood. Processes involved in learning, memory, attention and executive function continue to evolve during these years. Exposure to environmental pollutants during fragile developmental periods is therefore a huge concern.

Also read: Delhi Air Pollution: PM2.5 Exposure May Raise Type 2 Diabetes Risk By 16%, Study Finds

Effects On Learning And Academic Performance

Difficulties in paying attention, memorising and processing complex information can make it harder for children to follow lessons in the classroom.

“Prolonged exposure to high levels of air pollution has been associated with difficulties in concentration, attention, information processing and memory. This may also affect a child's learning abilities and academic performance over time. Although the extent of the impact varies depending on the duration and intensity of exposure, parents should take preventive measures,” says Dr Singla.

What Does Science Say?

Also read: Delhi Breathes Toxic PM2.5: Study Finds 9 Million Lives Could Be Saved Globally By Meeting WHO Air Quality Limits

Several studies suggest that air pollution exposure may be associated with poorer cognitive outcomes in children.

A review and meta-analysis published in Environmental Health in 2024 examined six studies involving 4,860 children across North America, Europe and Asia. It found a statistically significant association between higher PM2.5 exposure and lower IQ scores. The researchers reported that every 1 µg/m³ increase in PM2.5 was associated with a 0.27-point decrease in full-scale IQ.

A 2022 review of 86 studies also found evidence between particulate matter exposure and poorer executive function in children, specifically working memory. Executive function refers to a set of mental skills that help children plan, focus attention, remember instructions and manage multiple tasks.

Recent research based on data from the US Adolescent Brain Cognitive Development (ABCD) study also showed that PM2.5 exposure was linked with smaller hippocampal volumes and lower working-memory in young people.

The hippocampus is a brain region involved in learning and memory. The researchers suggested that exposure during both prenatal development and late childhood could affect brain structure and function.

What Can Parents Do?

While individual precautions cannot eliminate the pollution burden, they can help reduce exposure. Dr Singla advises parents to monitor AQI levels, limit outdoor activities during peak pollution hours and ensure adequate indoor ventilation. Other measures include:

• Check air quality before outdoor activities: Avoid outdoor sports, running and strenuous exercise when pollution levels are high.

• Keep windows closed during pollution episodes: Ventilate rooms when outdoor air quality improves. Where possible, use an air purifier with a HEPA filter.

• Use a well-fitting N95 mask: A respirator can reduce exposure to particulate matter when children need to be outdoors.

• Follow school advisories: Parents should stay informed about changes to outdoor classes, sports and school schedules during severe pollution days.

Former US President Joe Biden has shared an update on his battle with stage 4 prostate cancer, saying the disease has sometimes slowed him down but has not stopped him.

In a post on X, ahead of the November 17 release of his memoir, PROMISE ME, AMERICA, Biden revealed that he was diagnosed with prostate cancer while writing the book.

“Some days are better than others. It hasn't stopped me. But sometimes it slows me down,” he wrote, adding that he would be unable to participate in as many book-related conversations as he had hoped.

Biden said his doctors were encouraged by his response to treatment. He also thanked people for their prayers and wishes, saying their support meant a great deal to him, Jill and their family.

Biden also discussed his cancer diagnosis, treatment and its impact on his life in an interview with People, alongside his wife, former First Lady Jill Biden.

Joe Biden: Would Have Resigned If He Had Known About Cancer

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Biden addressed speculation about when he learnt about his diagnosis, saying, “We let the public know when I found out.”

He said he initially experienced recurring pain, prompting Jill to question why men in their 70s were not routinely tested. Subsequent tests revealed that his prostate cancer had metastasised to the bone.

Biden also said he would have stepped down from the presidency had he known his discomfort was caused by cancer, People reported.

“If I had known that I was feeling lousy because I had cancer, I would have resigned,” he said, adding that he did not believe an 80-year-old man with cancer should be running for president.

The diagnosis changed the couple's plans for life after the White House, including travelling.

“Because of that metastasis, he will always have cancer,” Jill said. “It changes your life, it changes your perspective about life. So now we're on a new journey.”

Biden said he remained hopeful and was feeling good. He takes eight pills a day and has undergone two tests to check whether the cancer has spread further. He said the results indicated that it had not.

“I still have all my faculties. I still have my physical faculties as well. So we're hopeful,” he said.

Jill Biden On The Challenges Of Caregiving

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Meanwhile, Jill described the emotional and physical demands of caring for her husband, saying it was different from looking after her parents or in-laws.

“It's just a lot different, I think, when it's your spouse because of the difference in the relationship,” she said.

Her daily routine now includes ensuring Biden eats well, exercises and takes his medication, as well as communicating with his doctors.

“I have seen how hard it is, how really emotionally hard it is, physically hard to go through each day,” she said.

The couple also discussed their family life and time with their grandchildren as they approach their 50th wedding anniversary.

What Is Prostate Cancer?

Prostate cancer develops in the prostate, a gland found only in males, located below the urinary bladder and in front of the rectum.

Nearly all prostate cancers develop from glandular cells and are classified as adenocarcinomas.

In 2020, an estimated 1.4 million new cases and 370,000 deaths from prostate cancer were reported worldwide. It was the most frequently diagnosed cancer among men in 112 countries and the leading cause of cancer deaths among men in 48 countries.

According to the US Centers for Disease Control and Prevention (CDC), 255,395 new prostate cancer cases were reported in the US in 2022, making it the most commonly diagnosed cancer among American men that year.

What Are The Symptoms Of Prostate Cancer?

Symptoms may include:

• Blood in the urine or semen
• Difficulty urinating
• Erectile dysfunction
• Bone pain
• Unexplained weight loss.