When was the last time you measured your waistline? If you assume that BMI is the only number to focus on when it comes to your health, think twice. New research has revealed a shocking revelation—your waist circumference might be a far better predictor of men's cancer risk than BMI.

The study finds that for each 4-inch increase in waist size, a man's risk of cancer increases by a staggering 25%. Meanwhile, BMI, commonly regarded as the gold standard for assessing obesity, raises cancer risk by only 19% for the same weight gain. So, if you've been dismissing that pesky belly fat, it's time to take notice.

But why is your waistline so important? The reason is visceral fat—the hidden, deep fat that accumulates around your organs. Unlike other body fat, visceral fat is a stealthy troublemaker, causing inflammation, insulin resistance, and abnormal blood fat levels—all of which combine to create a cancer-perfect storm.

Obesity has been associated with an increased risk of numerous health conditions, including cancer, for decades. The research, though, indicates that a specific measure of the body—waist circumference—may be an even more reliable forecaster of cancer risk in men than the more frequently employed Body Mass Index (BMI). This finding emphasizes the need to pay particular attention to the distribution of fat and not merely to the weight of the body.

BMI has been the go-to measure for years for gauging health risks related to obesity. New research, though, that appears in The Journal of the National Cancer Institute indicates that waist measurement is a better predictor of cancer risk in men. According to the research, four more inches (10 cm) around the waist will add 25% to a man's cancer risk. Conversely, a 3.7 kg/m² rise in BMI (from a BMI of 24 to 27.7) increased cancer risk by only 19%.

Why is waist circumference a better predictor, then? Unlike BMI, which measures weight relative to height, waist circumference actually measures abdominal fat—specifically, visceral fat. This type of fat encircles internal organs and is also linked to higher levels of inflammation, insulin resistance, and abnormal blood lipids, all of which are factors in cancer growth. BMI, however, does not measure fat distribution, so two individuals with the same BMI can have very different levels of health risk depending on where fat is deposited on their bodies.

Why Men Are at Higher Risk?

Interestingly, the research identified a significant difference between men and women when it came to waist circumference and cancer risk. Although waist circumference and BMI were linked with obesity-related cancers in women, the relationship was weaker than for men. An increase of 12 cm (4.7 inches) in waist size or a 4.3 rise in BMI (from 24 to 28.3) raised the cancer risk in women by just 13%—a much lower percentage than for men.

Experts credit this difference to the way that fat is stored in the body. Men are more likely to carry fat around the abdomen, especially as visceral fat, which is more metabolically active and associated with cancer-producing biological alterations. Women, by contrast, store fat in peripheral sites such as the hips and thighs, where it is less likely to drive systemic inflammation and metabolic disturbances.

A possible reason is that men tend to depot fat more in the visceral regions, whereas women tend to carry more subcutaneous and peripheral fat," wrote the researchers. "This may render waist circumference a more robust risk factor for cancer in men and account for why waist circumference provides additional risk information beyond BMI in men but not women."

Cancer Types Most Linked to Abdominal Fat

The research used the International Agency for Research on Cancer (IARC) data to define obesity-related cancers. These cancers are esophageal (adenocarcinoma), gastric (cardia), colorectal, rectal, liver, gallbladder, pancreatic, renal, and thyroid cancers, and multiple myeloma and meningioma. In men, abdominal obesity is especially significant in raising the risk of these cancers through high levels of insulin and markers of inflammation.

For women, the research proposes that both waist circumference and hip circumference may give a more accurate estimate of visceral fat and cancer risk. "Adding hip circumference to risk models could strengthen the link between waist circumference and cancer, especially in women," researchers observed.

What This Means for Men's Health and Cancer Prevention?

With these results, doctors advise men to be more mindful of their waistline than only their BMI. Waist size is an easy method to gauge health risk, and its maintenance through lifestyle changes might be the key to cancer prevention.

How To Reduce Cancer Risk In Men?

Track Your Waist Size: Regularly measure your waist circumference and try to keep it in a healthy range (below 40 inches for men, according to medical advice).

Eat a Balanced Diet: A diet containing high fiber, lean protein, and healthy fats can assist in limiting visceral fat gain.

Exercise Consistently: Regular exercise with a combination of aerobic and strength training will help maintain a healthy waistline.

Control Stress and Sleep: Persistent stress and inadequate sleep tend to cause weight gain, especially in the midsection of the body.

Regular Health Screenings: Early identification of cancer risk factors through regular screening can greatly enhance long-term health status.

Sleep disturbances are among the most debilitating symptoms of Alzheimer’s disease. It often appears years before significant memory decline and other symptoms.

A new study from researchers at the University of Kentucky suggests that this sleep loss may not be permanent.

Instead, it could be driven by an immune response in the brain that may be reversible, sparking hope for new treatments.

Published in the journal Alzheimer’s & Dementia, the study found that brain immune cells called microglia, rather than amyloid plaques themselves, are the primary cause of sleep disruption in Alzheimer’s disease.

In mouse-based trials, researchers were able to restore more than two hours of sleep per day by temporarily removing these immune cells, without reducing amyloid plaques.

Can Sleep Be Restored In Alzheimer’s Patients?

For years, scientists believed that sleep problems in Alzheimer’s were caused by the accumulation of amyloid plaques or the gradual death of brain cells. However, this study points in a different direction.

Researchers discovered that when amyloid plaques begin forming in the brain, they activate microglia, the brain’s resident immune cells.

Instead of protecting the brain, these cells cause inflammation that keeps brain circuits active, preventing sleep.

Using a drug called pexidartinib (PLX3397), the researchers temporarily depleted around 87% of microglia in Alzheimer’s mouse models.

This restored over two hours of daily sleep, particularly non-rapid eye movement (NREM) sleep, which is essential for tissue repair, memory strengthening, and clearing waste products from the brain.

Notably, the improvement occurred without changing amyloid plaque levels, suggesting that inflammation is manageable.

Also read: Captain ‘Sully’ Sullenberger, ‘Miracle On The Hudson’ Pilot, Reveals Early-Stage Alzheimer’s Diagnosis

'Paradigm Shifting' Findings

Lead researcher Dr. Shannon L. Macauley, associate professor of physiology at the University of Kentucky College of Medicine, said, “Basically, we showed that it is not the plaques themselves, or solely dysfunctional neurons, that cause sleep loss but actually microglia.

Microglia are immune cells that, when they respond to plaques, kick off this elaborate cascade of inflammation, as if the microglia are partying all night, and keeping the brain awake.”

She also highlighted why losing restorative sleep can accelerate disease progression.

“That restorative sleep is super important for physical repair, learning and memory and washing out the toxins of the day. When Alzheimer’s patients lose this stage, they lose their brain’s primary cleaning cycle, creating a feed-forward loop that may drive further damage,” she explained.

First author Dr. Nicholas J. Constantino said one of the biggest surprises was that sleep problems did not worsen as amyloid plaques increased.

“I expected that as plaque burden became more severe, sleep disruption would also worsen. The disruptions in sleep… did not worsen by 18 months, despite more than double the amount of plaque burden,” Constantino said.

Also read: What Is Type 3 Diabetes? Insulin Resistance In The Brain That Could Trigger Alzheimer’s

Why Do Alzheimer’s Patients Lose Sleep?

Poor sleep and Alzheimer’s create a vicious cycle. Sleep deprivation reduces the brain’s ability to clear amyloid-beta and tau proteins, which can accelerate disease progression, while worsening sleep.

Sleep disturbances affect up to half of people living with Alzheimer’s disease. The disease disrupts sleep due to various reasons:

Overactive microglia: As shown in the new study, immune cells become chronically activated by amyloid plaques, releasing inflammatory signals that keep the brain in a heightened state of activity.

Damage to sleep-regulating brain regions: Alzheimer’s progressively affects areas like the hypothalamus and brainstem that regulate the sleep-wake cycle.

Loss of NREM sleep: Due to lack of deep sleep, the brain’s ability to clear metabolic waste, including amyloid plagues weakens.

Circadian rhythm disruption: Degeneration of the brain’s internal clock leads to broken sleep and daytime drowsiness. This fuels confusion and agitation associated with the disease.

Obesity has always been considered as one of the contributors to heart disease, diabetes, and stroke.

Now, growing research suggests that excess body fat, particularly in your 40s and 50s, may also accelerate brain aging and raise the risk of long-term cognitive decline.

Researchers say that obesity is not just linked with memory problems but also to significant changes in the brain structure.

Maintaining a healthy weight, especially during midlife, could help prevent memory problems and overall cognitive decline.

Higher BMI Linked To Faster Brain Aging

A recent study by researchers at the University of Georgia followed more than 8,200 adults aged 50 years and older for nearly 24 years.

The researchers found that individuals whose body mass index (BMI) increased over time experienced faster declines in cognitive performance than it would with normal aging. Excess body weight affected several aspects of cognition, including memory, planning, decision-making, problem-solving, emotional regulation, and concentration.

Lead author Dr. Claire Sexton (University of Georgia College of Public Health) said, "Maintaining a healthy body weight throughout adulthood may be an important strategy for preserving cognitive health later in life."

The study adds to the evidence that preventing weight gain throughout adulthood could become crucial for reducing dementia risk.

Also read: Grade-1 Fatty Liver: More Indians Are Developing It at Lower BMIs. What's Behind the Shift?

How Does Obesity Affect The Brain?

Chronic Inflammation

Obesity causes chronic low-grade inflammation, which can potentially damaging neurons essential for learning and memory.

Insulin Resistance

The brain relies on glucose for energy. Insulin resistance, common in obesity, may impair how brain cells use glucose, affecting memory and thinking.

Reduced Blood Flow

Obesity increases the risk of hypertension, atherosclerosis and vascular disease, reducing blood supply to brain tissue and potentially accelerating cognitive decline.

Visceral Fat

Experts believe visceral fat, the fat surrounding internal organs, may be more damaging than body weight alone. It produces inflammatory chemicals linked to brain changes and dementia risk.

Also read: Beyond Weight Loss: Scientists Discover How Exercise Can Help Reverse Muscle Aging

Growing Evidence

The latest findings are supported by several years of research. A large review published in Practical Neurology concluded that obesity is associated with smaller hippocampal volume, temporal lobe atrophy, mild cognitive impairment and increased Alzheimer's disease risk.

Some studies have suggested that obesity during midlife may nearly double the risk of developing Alzheimer's disease or dementia later in life.

Another review on obesity and aging reported that higher BMI is associated with poorer verbal memory, slower information processing and reduced executive function, particularly among older adults.

In January 2026, researchers also used genetic analyses to suggest that obesity and high blood pressure may directly contribute to dementia.

Can The Risk Be Reduced?

With a few lifestyle improvements, overweight and obese individuals can maintain a healthy BMI, reducing the risk of faster brain ageing and cognitive degradation. Experts recommend focusing on overall metabolic health rather than the number on the weighing scale alone.

Maintaining a healthy weight, regular exercise, controlling blood pressure, cholesterol and diabetes, following a Mediterranean diet, getting adequate sleep, remaining socially and mentally active can help maintain a healthy body weight.

Living with someone who has hepatitis can be worrying. People tend to immediately wonder whether they are at risk simply by sharing meals, hugging, or living under the same roof.

Fortunately, the answer depends on the type of hepatitis, and in most cases, everyday household contact does not spread the virus.

Dr. Shalimar, Prof. Department of Gastroenterology, AIIMS explains, "Hepatitis means inflammation of the liver. There can be many causes, but viral hepatitis is one of the most common. There are different hepatitis viruses, including A, B, C, D, and E. Some cause acute illness, while others can lead to long-term liver damage, including cirrhosis and liver cancer."

Experts say misinformation surrounding hepatitis often leads to unnecessary fear and stigma, causing patients to feel isolated. Understanding how different hepatitis viruses spread can help families protect themselves without avoiding normal interactions.

Can You Get Hepatitis By Living With Someone?

Dr Nanda Kishore M, Gastroenterology, Athulya Geriatric Care Hospital, answers our question, "No, Hepatitis is not a communicable disease that spreads through everyday contact such as hugging, holding hands, coughing, or sneezing."

For most forms of hepatitis, the answer is no. However, hepatitis B is spread through contact with infected blood and certain body fluids. Household transmission is possible, but it generally occurs when infected blood enters another person's bloodstream.

Possible household risks include sharing:

• Razors
• Toothbrushes
• Nail clippers
• Glucose monitoring devices
• Any item contaminated with blood

Also read: Can Hepatitis Be Completely Cured? Understanding What Treatment Can Achieve

Dr. Kishore says that the mode of transmission largely depends on the type of hepatitis infected.

He says, "Hepatitis A and E are predominantly spread via means of contaminated food and water, while Hepatitis B and C are transmitted through infected blood and certain bodily fluids."

Hepatitis B is preventable by vaccine. Household members of someone with chronic hepatitis B are usually advised to get tested and vaccinated if they are not already immune.

Dr. Shalimar says, "For hepatitis B, current treatment controls the infection, and newer therapies under development offer hope for a functional cure in the future. Vaccination has dramatically reduced hepatitis B in many parts of the world. Expanding vaccination coverage remains one of the most effective ways to prevent the disease."

Living with a hepatitis infected individual is generally safe given that basic hygiene and recommended precautions are followed strictly. Understanding these facts helps reduce unnecessary fear and stigma associated with it.

Also read: Grade-1 Fatty Liver: More Indians Are Developing It at Lower BMIs. What's Behind the Shift?

Importance of Screening & Prevention

Living with someone who has hepatitis does not mean you need to keep your distance. Instead, focus on practical precautions:

• Never share personal items that may come into contact with blood.
• Cover cuts and wounds.
• Wear disposable gloves while cleaning blood spills.
• Practice good hand hygiene.
• Ensure hepatitis B vaccination if recommended.
• Attend regular medical follow-ups if advised by your healthcare provider.

Dr. Ankur Jain, Associate Director & Unit Head, Gastroenterology, Hepatology & Endoscopy, Max Hospital, Dwarka, explains, "Hepatitis B and Hepatitis C continue to affect millions of people worldwide and remain major causes of liver cirrhosis and liver cancer. Individuals with a history of blood transfusions before routine screening, unsafe injections, or other risk factors should discuss screening with their physician.

He adds, "The liver has an extraordinary capacity to heal, but only if we identify problems early and address the underlying causes. Prevention, timely screening, and simple lifestyle modifications remain our most powerful tools in reducing the growing burden of liver disease in India."