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.

August 18 marks World Breast Cancer Research Day, a day that reminds us that every major breakthrough in cancer care has its roots in research. The medicines that are prescribed, the diagnostic technologies that we use, the targeted therapies that we offer and our growing understanding of why cancers develop and spread, are all outcomes of regular scientific research.

India carries one of the world's largest cancer burdens. According to IARC's GLOBOCAN 2022 estimates, India recorded approximately 1.41 million new cancer cases and more than 916,000 cancer deaths in 2022. Breast cancer alone was the leading cancer among Indian women and also the leading cancer overall.

India as a country, has a large and diverse patient population, significant clinical expertise, strong medical institutions and a pharmaceutical industry with enormous manufacturing capabilities. But there is a crucial gap between manufacturing what the world has already discovered and researching newer medical opportunities.

A significant proportion of cutting-edge cancer research continues to emerge from countries with substantially larger and more established research ecosystems. When scientific discoveries, new molecules, diagnostic technologies or treatment approaches are developed elsewhere, Indian patients benefit from them at a later stage.

We Need To Move Beyond A Few Centres Of Excellence

We have limited institutes that have made important contributions to cancer care and research. But considering India's population and cancer burden, the scale of research infrastructure needs to expand substantially. We need more dedicated cancer-research institutes, stronger university hospital industry collaborations, modern laboratories, biobanks, genomic databases, data-science capabilities and trained physician-scientists.

Cancer is not just one disease. It comprises of multiple biological subtypes, and the way a tumour behaves can vary significantly between individuals and populations. Therefore, India needs research that focusses specifically towards Indian patients.

Also read: Groundbreaking Experimental Vaccine May Prevent Pancreatic Cancer From Spreading, Early Trial Finds

Clinical Trials Can Be Part Of The Solution

India has a formal Clinical Trials Registry, and the registry currently records more than 100,000 trials across areas of medicine.

For eligible patients, participation in an appropriate clinical trial may provide access to an investigational therapy or treatment strategy that is not yet routinely available. Clinical trials generate evidence that can improve future treatment for thousands or millions of patients.

Also read: UK Set To Implement Stricter Protocol For Prostate Cancer Testing; Who Is Eligible To Get Tested?

Research Needs To Become A Policy Priority

We need to create an ecosystem that moves from discovery to translation to patient care. That means incentivizing research institutions and researchers, supporting young physician-scientists, strengthening public-private partnerships and making it easier for promising discoveries to move from laboratories into clinical development.

We need to have an ecosystem, where healthcare research, particularly research addressing diseases with an enormous Indian burden should receive a much greater and more targeted share of national research investment. A large, diverse population can generate valuable real-world evidence. Large patient cohorts can help researchers understand disease patterns. Indian genetic and molecular data can help answer questions that may not be adequately addressed through studies conducted in other countries.

From Manufacturing Medicines To Discovering The Next Generation Of Treatments

India has already demonstrated that it can serve the world as a pharmaceutical manufacturing powerhouse. We should look at also becoming the research hub for the world by combining our pharmaceutical manufacturing strength, clinical expertise, technology capabilities and patient population.

The opportunity is already in front of us.

What we need now is the policy ambition to implement it.

By Dr. Kapil Goyal, Consultant – Medical Oncology, Rajiv Gandhi Cancer Institute & Research Centre (RGCIRC)

If you believe having a healthy body mass index (BMI) means you have a low risk of heart disease, you may be wrong. A new study suggests that abdominal fat may predict cardiovascular disease risk better than BMI alone.

The study, published in the Journal of the American College of Cardiology (JACC), found that failing to account for waist circumference (WC) or waist-to-hip ratio (WHR) may lead to misclassification of cardiovascular disease risk.

“Indeed, it appears that WC and WHR reclassify risk defined by traditional BMI thresholds,” said Michael J. Blaha, director of clinical research at the Johns Hopkins Ciccarone Center for the Prevention of Cardiovascular Disease.

“We saw individuals with clinically determined normal weight who had elevated central adiposity and high WHR, associating them with higher risk across most outcomes,” Blaha added.

Why BMI Alone May Not Predict Heart Risk

BMI is calculated by dividing weight in kilograms by height in meters squared and is commonly used to diagnose overweight and obesity. However, BMI does not show where body fat is distributed.

• Visceral fat surrounds the internal organs in the abdominal area and is associated with chronic conditions such as heart disease and diabetes.
• Subcutaneous fat is located directly under the skin and is not as strongly associated with these conditions.

What Did the Study Find?

The study examined whether adding WC and WHR to BMI could better predict future cardiovascular risk. Researchers looked at more than 260,000 people over an average of 20 years. They found that central adiposity could identify cardiovascular risk that BMI alone may miss.

Among people classified as having normal weight by BMI:

• 5% had high waist circumference
• 18% had high waist-to-hip ratio

• 39% had high waist circumference
• 40% had high waist-to-hip ratio

• 9% had low waist circumference
• 45% had low waist-to-hip ratio

People with normal weight or overweight who had clinically defined high WC or WHR had a 15%–50% greater risk for most heart problems.

People with obesity and low WC did not have a significantly different risk of outcomes compared with those who had normal weight and low WC, except for all-cause mortality, for which their risk was significantly lower.

“Our findings emphasize the critical role of identifying elevated central adiposity, even in individuals with a normal BMI or with a BMI in the overweight range. Relying solely on BMI may result in misclassification of cardiovascular risk across a wide range of cardiovascular outcomes,” said Zeina A. Dardari, lead author of the study.

“We encourage clinicians to consider central adiposity distribution across the entire BMI spectrum when evaluating cardiovascular risk in primary prevention settings,” she added.

What Were the Study's Limitations?

The researchers did not have information on several factors that can influence cardiovascular disease risk, including:

• Physical activity
• Diet
• Genetic risk for obesity

The study also included only one assessment of waist circumference and waist-to-hip ratio. This limited the researchers' ability to understand how changes in abdominal fat accumulation over time may influence cardiovascular disease risk.

Organ donation is one of the most profound ways in which we can give the gift of life to another person. World Organ Donation Day, observed every year on August 13, is an opportunity to raise awareness about organ donation, address common myths and encourage more people to consider pledging their organs. India has a large number of patients waiting for organ transplants, including transplants of the liver, kidney, heart, pancreas, intestine and other organs and tissues.

Despite the significant need, organ donation rates remain low, with lack of awareness and several misconceptions continuing to be major barriers. One organ donor can potentially save multiple lives. However, for this to happen, it is important that people understand the process and make an informed decision about organ donation during their lifetime.

Busting Common Myths About Organ Donation

1. “My religion does not permit me to donate my organs.”

2. “Organs can only be donated after the heart stops beating.”

For most organs, donation after brain death is possible when the brain has permanently stopped functioning, but the heart is still beating, which generally occurs in an intensive care setting. Corneas can also be donated after death within a limited time period. This is why pledging your organs during your lifetime and discussing your decision with your family is important.

3. “Organ donation will disfigure or mutilate the body.”

Organ retrieval is performed by trained medical specialists in an operating theatre. The surgical incision is carefully closed after the procedure, and the body is not mutilated.

Also read: Post-Organ Donation And Transplant Care: How Can Donors And Recipients Stay Healthy?

4. “I can buy a kidney or liver for my family member.”

5. “If I donate a kidney, I will become weak or handicapped.”

A healthy person who is found suitable for living kidney donation through the required medical evaluation can generally continue their normal life after donation. The remaining kidney is capable of maintaining normal kidney function.

6. “A kidney donor has to take lifelong medicines.”

Kidney donation does not mean that a healthy donor has to take lifelong medication simply because they have donated a kidney. Some pain medication may be required during the initial recovery period, while the remaining healthy kidney continues to perform its function.

7. “I will have severe dietary restrictions after donating a kidney.”

According to the source material, kidney donors do not generally need specific dietary restrictions solely because they have donated a kidney, as the remaining kidney continues to maintain normal kidney function.

8. “I will not be able to have children after donating a kidney.”

Both men and women who donate a kidney can have children. For women, the source recommends waiting one year after donation before becoming pregnant to allow the body to recover completely.

9. “I am over 60, so I am too old to donate.”

Age alone does not determine whether someone can donate. The health of the donor and the condition of the organs are important considerations, and suitability is determined through medical evaluation.

Also read: World Organ Donation Day 2026: Too Old Or Too Sick To Donate Organs? Doctors Bust Key Myths

What Can We Do To Encourage Organ Donation?

• Consider pledging your organs during your lifetime and communicate your decision clearly to your family.

• Talk to your family, friends and colleagues about organ donation and help dispel common myths.

• Encourage community organisations to participate in creating awareness around organ donation.

• Do not assume that you are medically unfit to donate. A team of medical experts evaluates the donor and determines suitability.

• Organ donation is a completely voluntary decision. No individual should be pressured into donating an organ.

• Patients waiting for an organ transplant should approach a licensed transplant hospital and complete the necessary registration formalities, including through the NOTTO system.

Organ donation is ultimately about giving someone another chance at life. We should not take our organs with us; they can be used to save lives and give hope to those waiting for a transplant.

By Dr Sanjeev Gulati, Chairman, Nephrology, Fortis, Vasant Kunj