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.

Britons who regularly take a commonly used supplement are being urged to cut back if they notice four particular symptoms, as excessive intake can be dangerous and, in some cases, life-threatening. Vitamins and minerals are essential for keeping the body functioning properly. While most nutrients should ideally come from a healthy, balanced diet, many people choose to top up their intake with supplements.

Iron is one such supplement. This mineral plays a key role in making haemoglobin, the substance in red blood cells that carries oxygen around the body. When iron levels are too low, it can lead to iron deficiency anaemia. This condition may cause symptoms such as constant tiredness, low energy, shortness of breath, and heart palpitations. To avoid this, some people turn to iron supplements.

Could You Be Overdoing Iron Supplements?

The NHS has issued guidance on its website, warning that taking “too much” iron can cause side effects. These include:

• Constipation
• Feeling sick
• Being sick
• Stomach pain

If these symptoms appear, it may be a sign that your iron intake needs to be reduced. In children, taking too much iron can be particularly dangerous and may even be fatal.

The NHS states: “Very high doses of iron can be fatal, particularly if taken by children, so always keep iron supplements out of the reach of children.” For adults, a high dose of iron is classed as more than 20mg.

How Much Iron Do You Need?

• 8.7mg a day for men aged 19 and over
• 14.8mg a day for women aged 19 to 49
• 8.7mg a day for women aged 50 and over
• Women who continue to have periods after the age of 50 may need the same amount of iron as women aged 19 to 49

The Department of Health and Social Care (DHSC) says that “most people” should be able to meet their iron needs through a varied and balanced diet. But for those who do take supplements, the NHS advises: “Do not take too much as this could be harmful.”

It adds that taking 17mg or less of iron supplements each day is “unlikely” to cause harm. The guidance continues: “But continue taking a higher dose if advised to by a GP.”

Good sources of iron include:

• Liver (but this should be avoided during pregnancy)
• Red meat (though the DHSC advises limiting red and processed meat due to a possible link to bowel cancer)
• Beans, such as red kidney beans, edamame beans, and chickpeas
• Nuts
• Dried fruit, including dried apricots
• Fortified breakfast cereals
• Soybean flour

Symptoms Of Iron Deficiency Anaemia

• Tiredness and low energy
• Shortness of breath
• Noticeable heartbeats, also known as heart palpitations
• Skin that appears paler than usual
• Headaches
• Ringing, buzzing, or hissing sounds in the ears or head, known as tinnitus
• Food tasting unusual
• Itchy skin
• A sore tongue
• Hair loss, with more hair coming out during brushing or washing
• Craving non-food items such as paper or ice, a condition called pica
• Difficulty swallowing, known as dysphagia
• Painful open sores at the corners of the mouth
• Changes to the nails, including spoon-shaped nails
• Restless legs syndrome

People in the UK who take a commonly prescribed medication are being reminded to follow a strict cut-off time. Ignoring this guidance could lead to disrupted sleep.

What Is Bumetanide?

Bumetanide is a diuretic, a type of medicine that helps the kidneys remove excess salt and water by increasing urine production. In the UK, it is prescribed for heart failure, a condition that affects close to one million people. Bumetanide is only available with a prescription and comes in tablet form as well as a liquid that is taken by mouth.

Bumetanide: NHS Says Avoid Taking It After 4 PM

The NHS website lists several key points patients should be aware of when using bumetanide. One of the most important relates to timing. According to NHS advice, bumetanide should not be taken after 4pm, as doing so may cause frequent urination during the night.

The NHS states: “Do not take bumetanide after 4pm or you may have to wake up in the night to go to the toilet.” Alongside this warning, the guidance also includes recommendations on when to take the medicine and what foods to avoid.

“You'll usually take bumetanide once a day, in the morning or afternoon – or twice a day, in the morning and afternoon,” the NHS explains. “Most people need to pee about 30 minutes after taking bumetanide, and again within a few hours.” The NHS also advises avoiding foods high in salt, such as processed foods or ready meals, as well as salt substitutes like Lo Salt, as these can interfere with how the medicine works. However, it adds: “You can take bumetanide with or without food.”

Some people are advised to take extra care when using bumetanide. The NHS says it is important to inform your doctor if you have:

• Ever had an allergic reaction to bumetanide or other medicines
• Low blood pressure (hypotension)
• Signs of dehydration, including thirst, a dry mouth, or dark-coloured urine
• Liver disease
• Diabetes
• Difficulty passing urine
• Gout

If you are due to have a glucose test, you should also let your doctor know that you are taking bumetanide.

Bumetanide: Common Side Effects

There are several common side effects associated with bumetanide that occur in more than one in 100 people. The NHS says there are ways to manage these symptoms:

• Needing to urinate more often than usual
• Feeling thirsty
• Dry mouth
• Headaches
• Feeling dizzy or confused
• Muscle cramps or muscle weakness

Patients are advised to speak to a doctor or pharmacist if the suggested coping measures do not help, or if side effects continue or worsen after a few days.

Bumetanide: Serious Side Effects

Serious side effects are uncommon, according to the NHS. However, you should contact your doctor or call 111 immediately if you experience:

• Unexplained bruising or bleeding, a high temperature, sore throat, or mouth ulcers, which may indicate a blood disorder
• Ringing in the ears (tinnitus) or hearing loss

The NHS also notes: “In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to bumetanide.” In 2023, the UK faced a national shortage of bumetanide, which was expected to ease in 2025.

Because of this shortage, many patients were switched to furosemide, another diuretic that is also subject to the same 4pm timing advice.

Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider regarding any questions about medications, health conditions, or before making changes to your treatment plan.

Scientists have found that a single dose of the shingles vaccine may do more than protect against the painful viral infection. It may also help slow biological ageing in older adults. Researchers from the University of Southern California say the vaccine, commonly given to seniors, could have benefits beyond shingles prevention. The findings come from a study involving over 3,800 people, which showed that vaccinated individuals had fewer signs of biological ageing and lower inflammation levels than those who had not received the shot.

What Is Shingles?

Shingles is a viral condition known for causing a painful, blistering rash. It can appear on different parts of the body but usually shows up as a band of blisters running along one side of the torso. The infection is caused by the varicella-zoster virus, the same virus responsible for chickenpox. Even after recovery from chickenpox, the virus remains dormant in the body and can reactivate years later as shingles, according to the Cleveland Clinic.

While shingles is not usually life-threatening, it can be extremely uncomfortable. Vaccination significantly reduces the risk of developing shingles. Starting treatment early can shorten the duration of the illness and lower the risk of complications. One of the most common complications is postherpetic neuralgia, a condition where nerve pain continues long after the rash has healed.

Shingles Vaccine May Slow Biological Aging In Older Adults

A recent study by the University of Southern California suggests that the shingles vaccine recommended for older adults may help slow down ageing at a biological level, in addition to preventing infection. “While more research is needed to confirm and expand on these results … our findings add to growing evidence that vaccines may support healthy ageing, not just prevent short-term illness,” said Eileen Crimmins, a co-author of the study, in a statement. To explore this further, Crimmins and her team focused on people who had received the shingles vaccine.

Shingles Virus Reactivates Later in Life

Although chickenpox is now uncommon in children, with cases dropping by over 97 percent since the vaccine became part of routine childhood immunisation in 1995, more than 95 percent of adults in the US were infected before that change, according to the CDC. At present, around one million Americans develop shingles every year.

Health authorities recommend that adults aged 50 and above receive two doses of the shingles vaccine. This not only lowers the risk of infection but also reduces the chances of postherpetic neuralgia, a lingering nerve pain that can persist for months or even years after the rash disappears.

Why Biological Age Matters More Than Your Actual Age

The researchers analysed data from more than 3,800 adults aged 70 and older, using information from the nationally representative US Health and Retirement Study. Blood samples were examined to assess seven different indicators of biological ageing.

Unlike chronological age, which simply counts years lived, biological ageing reflects how well the body’s organs and systems are functioning over time.

Shingles Vaccine: Lower Inflammation, Healthier Ageing

Results showed that vaccinated participants had noticeably lower levels of inflammation, a key factor linked to age-related conditions such as heart disease, frailty, and cognitive decline.

“By reducing this ongoing inflammation, possibly by stopping reactivation of the shingles virus, the vaccine may help support healthier ageing,” explained Jung Ki Kim, the study’s lead author.

“Although the exact biological processes are still unclear, the vaccine’s ability to lower inflammation makes it a promising tool in broader efforts to slow age-related decline and improve resilience,” she added.

Shingles Vaccine: What The Blood Markers Reveal About Ageing

The study also found that vaccinated individuals experienced slower changes in how genes are switched on and off, and in how genetic instructions are translated into proteins. These processes are known as epigenetic and transcriptomic ageing and are considered important markers of biological ageing.

When all seven ageing measures were combined into a single biological ageing score, those who had received the vaccine showed slower ageing overall compared with people who had not been vaccinated.

An image collage containing three visuals shows a gloved hand drawing blood into a tube, a longevity test kit with a swab and vial placed on an orange surface, and a screenshot of longevity test results displaying a bar chart of 117 biomarkers and a biological age of 29.3 years, which is 13.5 years younger than the actual age.

I gave lots of blood for six longevity tests — here’s how long I can expect to live

Can Vaccines Protect More Than Just Against Infection?

The findings build on earlier research that has linked adult vaccinations, including shingles and flu shots, to a lower risk of dementia and other neurodegenerative conditions such as Parkinson’s disease.

“This research strengthens the idea that vaccines may help promote healthy ageing by influencing biological systems beyond infection control,” said Kim, who is also a research associate professor of gerontology at USC.

Shingles Vaccine: Long-Term Benefits Seen Years After Vaccination

Importantly, the benefits appeared to last. Even participants who had received the shingles vaccine four or more years before their blood samples were taken still showed slower epigenetic, transcriptomic, and overall biological ageing compared to those who had not been vaccinated.

“These results suggest that shingles vaccination affects key processes associated with ageing,” said Crimmins, who is a USC University Professor and AARP Professor of Gerontology.

If future research confirms these findings, it could offer Americans another reason to get vaccinated and help improve vaccination rates, which remain low. Despite a rise during the pandemic period, only 30.1 percent of eligible Americans had received the shingles vaccine as of 2022.

The study highlights the potential for common vaccines to do more than prevent disease. They could play a significant role in promoting resilience, lowering inflammation, and supporting healthier ageing, especially in older adults.