We have all seen movies where right before the hero starts fighting, he cracks his knuckles and makes it look like the coolest thing in the world! But then our parents told us that you should not crack your knuckles because that weakens your grip and hand strength. But is that true? While many people do say that they experience a small loss in strength immediately after they crack their knuckles, but are their long-term effects to it? And what is the sound actually coming from?

The reason why people crack their fingers is because the evident and sharp crack noise causes a sense of relief. Many people also do it when they have done an activity that required them to work with their hands a lot like typing or sewing, giving themselves a sense of satisfaction, similar to stretching after doing hard work. That "crack" sound can make some people cringe, while others find it strangely satisfying. Cracking your knuckles is a pretty common habit, but there are a lot of misunderstandings about it. Some people do it without even thinking, others can't stand the noise, and some can't crack their knuckles at all. You might have been told as a kid that it causes arthritis or makes your fingers swell up. But those are just old wives' tales. There's a real science behind this habit, and it's more interesting than you may think.

Why Do Knuckles Make That Popping Sound?

The "crack" isn't actually bones breaking or anything bad happening to your joints. It's a normal thing called "crepitus." This just means harmless popping, snapping, or grinding sounds that come from your joints. The main reason you hear this sound is because of gas bubbles in the fluid that cushions your joints. This fluid is called synovial fluid. When you move or stretch, these tiny bubbles form and then pop, making the sound. It's totally normal and doesn't hurt you. Sometimes, especially in bigger joints like your knees, shoulders, or ankles, the sound can also happen when the stretchy tissues that connect your bones (ligaments and tendons) move slightly and then snap back into place.

After you crack your knuckles, you can't usually do it again right away. You have to wait a bit. That's because the gas bubbles in your joint fluid have already popped, and it takes a little while for them to build up again. While cracking your knuckles doesn't give you arthritis, doing it too much might cause some problems. Doctors say that cracking them too often could make your joints a little wobbly and might even make your grip weaker. Also, if the stretchy tissues in your joints keep snapping over your bones, they can get irritated and sore.

When Joint Popping Might Mean Something More

Sometimes, a pop in your joint is just like cracking your knuckles, nothing to worry about. But other times, it can be a sign of something else. As we get older, the cushiony stuff in our joints, called cartilage, can start to wear down. This cartilage helps your bones move smoothly. When it gets thin or uneven, the bones can rub together, and that can make a grinding or popping sound. This is different from the pop you get from gas bubbles. If this grinding sound happens along with pain, it could be a sign of osteoarthritis. This is a type of joint problem that's more common in older people, but younger people can get it too, especially after a joint injury. If your joints hurt, especially in the morning or after you've been sitting still for a while, feel wobbly, or are hard to move, it's a good idea to see a doctor.

Keeping the television on while falling asleep or leaving a light on in the bedroom may feel reassuring, but new international research suggests it could seriously affect heart health. A recent study has found that exposure to light at night significantly raises the risk of heart disease, even if a person believes they are sleeping well.

Sleeping With Lights On Could Harm Your Heart, Study Warns

The findings come from a large, long-term study carried out by researchers in Australia and the United States. The team followed nearly 90,000 adults in the United Kingdom over a period of nine years. Participants were given light sensors to accurately measure how much light they were exposed to during sleep.

Researchers tracked cases of heart attack, heart failure, and stroke throughout the study period. The results were striking. Compared to people who slept in complete darkness, those exposed to light at night faced a 56 percent higher risk of cardiovascular problems. The risk of heart failure increased by 47 percent, while the likelihood of coronary artery disease rose by 32 percent. The study noted that this risk was particularly higher among women. The risk of stroke was also found to be up to 30 percent higher.

Why Night-Time Light Is Dangerous

According to the research, published in JAMA Network Open, the main reason behind this increased risk is disruption of the body’s circadian rhythm. This internal biological clock regulates sleep, hormone release, metabolism, and other vital functions.

Artificial light at night interferes with this natural rhythm, pushing the body into a state of imbalance. Over time, this ongoing disruption places added strain on the cardiovascular system. Researchers warned that for people over the age of 40, exposure to light during sleep is emerging as a significant risk factor for heart disease.

Professor Frank Scheer, a neuroscientist at Brigham and Women’s Hospital, believes doctors should look beyond sleep duration when assessing patients’ sleep habits. He says physicians should also ask about bedroom conditions, including light exposure.

“There is no harm in keeping the bedroom completely dark,” he explained. “In fact, it is extremely beneficial for overall health.”

Simple Tips For Better, Heart-Healthy Sleep

Experts suggest a few practical steps to reduce light exposure at night:

• Turn off the television, mobile phones, and laptops before going to bed
• If light is needed for safety, keep it below 5 lux, roughly equivalent to the soft glow of a few candles
• Use thick, dark curtains to block out streetlights and outside glare
• Sleeping in darkness may seem like a small change, but researchers say it could play an important role in protecting heart health over time.

Researchers also noted that many people underestimate how much light they are exposed to at night. Even dim sources such as alarm clocks, charging indicators, or light filtering in from nearby buildings can affect the body’s natural night-time processes. Over years, this low-level but constant exposure may quietly increase the risk of high blood pressure, insulin resistance, and weight gain, all of which are closely linked to heart disease. The study reinforces a growing body of evidence that sleep quality is shaped not just by how long we sleep, but by the environment we sleep in.

A neurologist has spoken about a simple daily practice that may help guard against cognitive decline, and it requires just six minutes. Dr Clint Steele, a specialist in the brain and nervous system, works with patients to improve quality of life by strengthening brain function and preventing, and in some cases reversing, conditions such as dementia.

What Is Dementia?

Dementia is an umbrella term used to describe a significant decline in mental function that is serious enough to affect everyday life. It commonly impacts memory, thinking, and reasoning skills. Dementia itself is not a single disease but a collection of symptoms caused by underlying conditions such as Alzheimer’s disease or vascular dementia. Common signs include memory problems, confusion, difficulty finding words, changes in mood or behaviour, and trouble completing familiar tasks.

These symptoms usually worsen over time and are not considered a normal part of ageing. Although there is no cure, treatment options can help manage symptoms, and early diagnosis plays an important role in care planning.

Dementia: Signs And Symptoms

The signs of dementia can differ from person to person. Some common examples include difficulty with short-term memory, misplacing personal belongings like a purse or wallet, trouble managing finances or paying bills, challenges with planning or cooking meals, forgetting appointments, and becoming disoriented when travelling outside familiar areas.

Dementia symptoms tend to be progressive, meaning they often begin subtly and gradually become more severe over time, eventually interfering with daily functioning. If you or someone close to you notices ongoing memory issues or changes in thinking or behaviour, it is important not to dismiss them.

Six-Minute Daily Routine That May Help Slow Dementia Risk

The 56-year-old expert says that reading for six minutes a day could meaningfully lower the risk of dementia, Alzheimer’s disease, Parkinson’s disease, and other neurological conditions. In a TikTok video that has since been viewed thousands of times, Dr Steele points to long-term research showing that strengthening what is known as “cognitive reserve” may help prevent or reduce the likelihood of dementia and similar disorders, as per Mirror.

Why Cognitive Reserve Matters

According to Dr Steele, one way to support cognitive function is by learning new skills, such as picking up a foreign language, learning to dance, or simply reading a book for at least six minutes each day. “Reading six minutes a day actually lowers your risk of dementia, Alzheimer’s, Parkinson’s disease and more,” he told What’s The Jam.

He explained that reading helps build cognitive reserve, which refers to the brain’s ability to adapt. “Adaptability is so important because when you encounter stress, you want your brain to be able to adjust to that stress, respond in the right way, and then, once the stress has passed, adapt again and settle down,” he said.

A Small Daily Commitment

“One of the most important things you can do is read six minutes a day, according to the research, and that will help,” Dr Steele added. Based in Maine and Florida in the US, he has spent 34 years focused on brain health and dementia prevention.

Public Response To The Advice

His TikTok video has also drawn hundreds of likes and comments. One viewer wrote: “Normally read at least 100 books a year, plus the Bible, dance classes, acrobatics, clogging for at least six years, at 84 still moving, just slower, my mom had Alzheimer’s, so I do know!”

Another commented: “I still enjoy reading news every day.” A third added: “Another really good one is fine art, probably why so many older people take up painting.”

Students gaming more than 10 hours a week can have long-lasting negative effects on their physical and mental health, a new Australian study suggests.

Researchers from Curtin University, Perth have found that playing online games for over 10 hours can worsen diets, increase body weight and led to poorer sleep than lighter gamers.

Professor Mario Siervo, Curtin School of Population Health said of the results: "What stood out was students gaming up to 10 hours a week all looked very similar in terms of diet, sleep and body weight. The real differences emerged in those gaming more than 10 hours a week, who showed clear divergence from the rest of the sample."

What Did The Study Find?

Researchers surveyed 317 students across five Australian universities, with a median age of 20, to understand how time spent gaming each week might affect their diet, sleep, and body composition.

Students were categorized as low gamers (zero to five hours a week), moderate gamers (five to 10 hours) or high gamers, who played video games for more than 10 hours each week.

They found that low and moderate gamers showed largely comparable health outcomes but health indicators deteriorated sharply among students whose gaming time exceeded 10 hours a week.

The study found diet quality declined and obesity was more common once gaming exceeded 10 hours a week, with each extra hour linked to poorer diets even after accounting for other lifestyle factors. While high gamers recorded a body mass index (BMI) of 26.3kg/m2, low and moderate gamers fell within a healthier range, with median BMIs of 22.2kg/m2 and 22.8kg/m2 respectively.

Professor Siervo said: "Each additional hour of gaming per week was linked to a decline in diet quality, even after accounting for stress, physical activity and other lifestyle factors."

Additionally, sleep quality was generally poor across all groups but students who played video games for moderate or high amounts of time reported worse sleep than low gamers.

Despite clear results, the expert added that the study does not prove cause and effect but shows excessive gaming is linked to higher health risks, while low to moderate play appears largely fine.

Why Is Playing Video Games Bad For You?

"Our data suggests low and moderate gaming is generally fine, but excessive gaming may crowd out healthy habits such as eating a balanced diet, sleeping properly and staying active.

"Because university habits often follow people into adulthood, healthier routines such as taking breaks from gaming, avoiding playing games late at night and choosing healthier snacks may help improve their overall well-being," Professor Siervo said.

Playing video games for excessive amount of time has also been linked to paving the way for mental health problems such as anxiety, depression, aggression and poor emotional control as well as social/life problems including neglecting responsibilities, isolation, poor relationships, academic/career impact.

Moreover, previous research has also found that playing games for over three hours straight significantly raises the risk of physical issues. Sessions exceeding this time frame can lead to eye fatigue, headaches, neck pain and wrist pain, regardless of the player's age or gender.

This study was published in Nutrition on January 16.