From controlling body temperature and flushing out toxins, adequate hydration plays a vital role in our general health and well-being, water is a life essential. However, while dehydration garners significant attention, overhydration, or drinking excessive amounts of water, is a condition that can have serious and sometimes fatal consequences.

Although it may sound bizarre since drinking water is said to be the solution for most health related problems it is important to recognize how much water is considered "too much" or the risks involved with being overhydrated can maintain a healthy balance.

What Is Water Intoxication?

Water intoxication, also termed hyperhydration, water poisoning or water toxemia, develops when an individual drinks much more water than the kidney can excrete. The main function of the kidneys in the human body is the processing and excretion of excess water. However, the human kidneys can process only up to 0.8 to 1.0 liters of water at a time. Drinking an amount that exceeds this may overwhelm the kidneys and put the electrolyte balance out of sync in the human body.

Electrolytes, especially sodium, are essential in maintaining fluid balance within and outside cells. Hyponatremia is the condition when sodium levels fall below 135 mmol/L, resulting from excessive water intake. This causes water to shift into cells, swelling them. In the brain, this can cause severe complications, including coma or even death.

Symptoms of Water Intoxication

The symptoms of water intoxication vary from mild to severe. Early symptoms are often similar to dehydration, which makes self-diagnosis challenging. Common symptoms include:

• Headaches
• Nausea and vomiting
• Muscle cramps or weakness
• Fatigue or drowsiness
• Confusion and disorientation

In more serious cases, water intoxication can cause seizures, loss of consciousness, or swelling in the brain. These complications can be fatal if left untreated.

A notable case occurred in 2007 when a woman participating in a water-drinking contest tragically died after consuming nearly two gallons of water in under two hours. More recently, actress Brooke Shields experienced a grand mal seizure attributed to excessive water consumption.

Causes of Water Intoxication

Water intoxication is rare, but certain scenarios can increase the risk:

1. Sporting Events and Endurance Training

These endurance athletes are prone to water intoxication, especially if they drink large amounts of water without replacing lost electrolytes. Hyponatremia usually happens during long races or marathons as individuals mistake fatigue and muscle cramps for dehydration and continue drinking water in excess.

2. Military Training

Overhydration among military personnel is usually due to severe physical activity in extreme environmental conditions. The total number of hyponatremia cases documented from 2007 through 2022 for the active duty in the United States exceeds 1,600, with a note to this problem on exertion-related overhydration.

3. Mental Health Conditions

Compulsive water drinking, known as psychogenic polydipsia, is linked with some mental illnesses such as schizophrenia and psychosis. People with these conditions tend to drink too much water, causing a hazardous electrolyte imbalance.

4. Drug Abuse

Drugs such as MDMA (ecstasy) raise the body temperature and make people thirsty, and at times, some people tend to drink excess water at events like music festivals. MDMA also leads to urine retention, thus exacerbating the dangers of water intoxication.

How Much Water Is Too Much?

The exact amount of water that causes intoxication varies from one person to another. However, drinking more than 1 liter of water per hour for several hours raises the risk. For healthy individuals, the risk of overhydration is low unless taking part in extreme physical activity or ignoring thirst cues.

Certain medical conditions, such as kidney or liver disorders, can impair the body's ability to process fluids, and even moderate water intake may be harmful. Similarly, certain medications, such as diuretics and antipsychotics, can affect the perception of thirst or fluid regulation.

How Much Water Is Enough?

The widely touted recommendation of eight 8-ounce glasses of water per day has little basis in fact. According to the National Academy of Medicine, a daily total fluid intake is about 15 cups (3.7 liters) for males and 11 cups (2.7 liters) for females, from beverage sources and from food. Usually, about 20 percent of daily hydration comes from foods such as fruits and vegetables.

A better rule of thumb is to listen to your body and drink water based on thirst. Use the color of your urine as an indicator:

• Light yellow urine indicates proper hydration.
• Dark yellow urine may indicate dehydration.

Older adults, whose thirst mechanisms may decline with age, should be proactive about maintaining hydration, especially during illness or hot weather.

Water Intoxication vs. Dehydration

The symptoms of water intoxication—such as headaches, fatigue, and muscle weakness—are similar to those of dehydration. If you are unsure which condition you are experiencing, seek medical attention immediately rather than self-treating with more water.

Preventing Water Intoxication

To avoid the dangers of overhydration:

• Drink water gradually throughout the day rather than consuming large amounts at once.
• Replace lost electrolytes post high-intensity exercise or heavy sweating.
• Consider using sports drinks or salty snacks to help replenish sodium.
• Keep track of fluid consumption during long-duration activities, and do not consume more water than the body is losing in terms of electrolytes.
• If on medications or have specific medical conditions, check with your doctor regarding the safety of drinking water.

For signs of severe water intoxication-including confusion, drowsiness, seizures, and loss of consciousness-customer is advised to seek medical assistance immediately. In the meanwhile, a salty snack would help to temporarily correct low sodium levels.

Hydration is important to health, but overhydration can be a serious risk; the secret is in finding a balance. Drink enough water to satisfy your body, but not so much that it overwhelms your system. Remember, water is life, but moderation keeps it that way.

Hyponatremia (low sodium level in the blood). National Kidney Foundation. 2023.

Water Toxicity. NIH. 2023

Exercise-Associated Hyponatremia: 2017 Update. Front Med (Lausanne). 2017

Update: Exertional Hyponatremia Among Active Component Members of the U.S. Armed Forces, 2007–2022

Tadalafil, a widely used drug for erectile dysfunction and enlarged prostate symptoms, may increase the risk of glaucoma, the leading cause of blindness, in men with lower urinary tract symptoms (LUTS), according to a new study.

Although the study identified a significant association, the researchers emphasized that it was observational and does not prove that tadalafil directly causes glaucoma.

However, they suggested that men taking tadalafil long-term for LUTS may benefit from regular eye examinations, particularly those with existing glaucoma risk factors such as a family history of the disease or ocular hypertension.

What the Study Found

Researchers from the National Taiwan University Hospital in Taipei, Taiwan, found that men taking tadalafil for LUTS were:

• 22% more likely to develop glaucoma.
• 33% more likely to develop primary open-angle glaucoma, the most common form of the disease.
• 32% more likely to develop ocular hypertension (high pressure inside the eye).
• 33% more likely to begin glaucoma treatment.

The findings were published in the British Journal of Ophthalmology.

Also read: Israeli Scientists Find Surprising New Benefit of Viagra: It May Help Stop Cancer Spread

How the Study Was Conducted

The researchers analyzed health data from 73,854 men aged 40 years and older with a history of lower urinary tract symptoms.

Half of the participants had been prescribed tadalafil or another phosphodiesterase type 5 inhibitor (PDE5i) for up to five years, while the remaining participants received other treatments.

The increased glaucoma risk remained consistent, particularly among men aged over 50 years.

Tadalafil: How It Works?

Tadalafil works by relaxing smooth muscles and improving blood flow. Besides treating erectile dysfunction, it is also prescribed to relieve urinary symptoms caused by an enlarged prostate, such as frequent urination and urgency.

Previous studies have linked PDE5 inhibitors to several eye-related side effects, and the new findings add to concerns about their long-term effects on eye health.

"Tadalafil use for lower urinary tract symptoms was associated with a significant increase in the risk of glaucoma, ocular hypertension, primary open-angle glaucoma and initiation of glaucoma treatment in a large, multinational, real-world cohort," the researchers concluded.

Read More: GLP-1 Drugs Like Mounjaro, Ozempic Linked To 82 Deaths In UK, 162 In US

What Is Lower Urinary Tract Symptoms

Lower urinary tract symptoms (LUTS) are common urinary problems that affect the storage or passage of urine. They are particularly common in elderly men and are often linked to conditions such as an enlarged prostate, an overactive bladder or problems affecting the body's fluid balance.

Common symptoms include:

• A weak or slow urine stream
• Difficulty starting urination
• A sudden, urgent need to urinate
• Frequent urination, especially at night
• Feeling that the bladder has not emptied completel

What is Glaucoma?

Glaucoma is a group of eye diseases that can damage the optic nerve, potentially leading to irreversible vision loss and even blindness if left untreated.

It is a chronic disease that affects an estimated 80 million individuals globally, according to the World Glaucoma Association.

A major challenge with glaucoma is its lack of symptoms in the initial stages. As a result, the condition is often diagnosed at an advanced stage, where treatment yields the least results. More than 75 percent of glaucoma cases globally remain undiagnosed.

When to see a doctor for glaucoma:

• Vision suddenly gets blurry
• Severe eye pain
• Headache
• Nausea
• Vomiting
• Rainbow-colored rings or halos around lights.

For years, diet sodas have enjoyed a pretty good reputation. They offered the sweetness without the sugar, the fizz without the guilt, and for many people, they became an easy replacement for regular soft drinks. It is not hard to see why. Whether it is an afternoon craving, something to sip with lunch, or a way to satisfy a craving without reaching for sugar, diet drinks have quietly become part of many people's daily routine. However, a major new study is making people look at those drinks a little differently. Researchers have found that people who regularly consumed higher amounts of artificial sweeteners showed faster declines in memory and thinking skills over time. It does not mean your occasional Diet Coke is suddenly a problem. But if you cannot remember the last day you went without one, the findings are definitely worth knowing.

What Researchers Found

The study followed 12,772 adults in Brazil over eight years, with the average age of participants being 52. It is the largest and longest study so far looking at how artificial sweeteners may be linked to brain health. Researchers examined seven commonly used low- and no-calorie sweeteners found in ultra-processed products like sodas, flavoured water, sugar-free yoghurt and low-calorie desserts. These included:

• Aspartame
• Saccharin
• Acesulfame-K
• Erythritol
• Xylitol
• Sorbitol
• Tagatose

Throughout the study, participants completed tests that measured memory, verbal fluency, and processing speed. After taking other health factors into account, researchers noticed a clear pattern. People who consumed the highest amounts of artificial sweeteners experienced cognitive decline 62% faster than those who consumed the least. According to the researchers, that difference was roughly equal to 1.6 years of additional brain ageing.

Even people in the middle consumption group showed a 35% faster decline, equivalent to about 1.3 years of brain ageing. Out of the seven sweeteners studied, six showed an association with faster cognitive decline. The only one that did not was the Tagatose.

The Results Were Strongest In Younger Adults

One finding stood out more than the rest. Most people tend to think of memory problems as something that only becomes a concern later in life. This study suggested that may not be the full picture. The link between artificial sweeteners and cognitive decline was strongest in adults under the age of 60. Researchers believe this could mean that the habits people build during midlife play a much bigger role in long-term brain health. The association was also stronger among people with diabetes, who are often more likely to choose artificially sweetened foods and drinks instead of sugary ones. Among all the areas tested, memory appeared to take the biggest hit.

Before You Throw Away Your Diet Coke, Read This

This is where the conversation becomes important.

“Our findings do not suggest that drinking an occasional diet soda is harmful,” Claudia Kimie Suemoto of the University of São Paulo said. “Rather, they raise questions about the potential consequences of frequent, long-term consumption of artificial sweeteners.”

The study was observational, which means it identified the link, but it cannot say for sure that the sweeteners themselves caused the decline. That is a big difference. Lead researcher Claudia Kimie Suemoto from the University of São Paulo said: “Based on our study alone, I would not tell someone to stop drinking diet soda because of concerns about cognitive impairment”.

The findings also support earlier research. A 2017 study from the Framingham Heart Study reported a similar association between artificially sweetened beverages and a higher risk of stroke and dementia. Scientists say the evidence is growing, but there is still more to understand before firm conclusions can be made.

Read Also: UK Woman Dies After Sudden Abdominal Pain Following Increase In Her Mounjaro Dose

So What Should You Do?

The answer is probably not to swear off diet soda forever. Instead, experts suggest taking a closer look at how often you are reaching for it. If one can has quietly turned into several every day, it may be worth cutting back little by little. Whenever you want a Diet Coke, go for plain water, sparkling water, unsweetened tea, or black coffee. This can help reduce your overall intake without making the change feel overwhelming. The goal is not perfection; it is balance.

There is no reason to panic over a single can. But if sugar-free drinks have become something you rely on every day without really thinking about it, this study is a good reminder that even habits that seem harmless deserve an occasional second look. Sometimes the healthiest changes start with asking a simple question: "Do I really need another one?"

When patients first hear the term "bone marrow transplant," they often picture a complex surgery involving the bones or spine. This is perhaps the most persistent misconception surrounding one of modern medicine's most remarkable achievements.

Unlike other organ transplants (kidney/ heart/ liver, etc), a bone marrow transplant is not a surgery at all! It is administered much like a blood transfusion, through a simple intravenous line. Yet this deceptively simple procedure can rebuild an entire blood-forming and immune system from scratch, offering a genuine cure for blood cancers and other serious blood disorders.

Bone marrow is the body's blood factory, producing the red cells that carry oxygen, the white cells that fight infection, and the platelets that prevent bleeding. At its heart lie blood-forming stem cells or the "parent cells" capable of generating every blood cell the body will ever need.

In leukemia and related cancers, these stem cells turn rogue, crowding out healthy ones. In several inherited disorders, the marrow simply fails to manufacture healthy cells at all. A transplant addresses the problem at its root, replacing defective stem cells with healthy ones.

I often explain this to patients using the language of farming. Before sowing fresh seed, a farmer clears the field of weeds. Similarly, before healthy stem cells can be transplanted, doctors must prepare the marrow through chemotherapy and, in select cases, radiation, a stage called conditioning. Once this was punishingly intensive, limiting transplants to the young and fit. Today, reduced-intensity regimens, which are carefully tailored to suit even the old or frail patients, have extended this option to older adults and those with other health conditions.

The transplant itself is almost anticlimactic in its simplicity: stem cells are infused through an IV, with no incision or operating theatre required. These cells possess a natural ability doctors call "homing": they find their own way into the bone marrow and settle there. Over two to four weeks, they begin producing healthy blood, a process called engraftment.

For decades, the greatest obstacle to transplantation was finding a matched donor. Traditionally, only a fully matched sibling would do, leaving many patients, particularly in a genetically diverse country like India, without options. That has changed decisively. Half-matched family transplants and unrelated donors identified through registries now succeed at rates that rival matched-sibling transplants. Nearly every patient today has a realistic path to a suitable donor.

Technology is reshaping this field further. Gene therapy is opening a new chapter for disorders such as sickle cell disease and thalassemia, correcting a patient's own stem cells in the laboratory rather than relying on a donor, though such therapies remain costly and available only in select countries for now.

Recovery, however, is a marathon, not a sprint. It can take months as the immune system rebuilds, requiring vigilant monitoring for infection and for graft-versus-host disease, in which transplanted immune cells attack the patient's own tissues. Advances in immunosuppressive and targeted therapies have greatly improved our ability to manage this complication, allowing most survivors to gradually return to work, education and family life.

A blood cancer diagnosis remains frightening, but treatment has advanced tremendously in two decades. Bone marrow transplantation is no longer experimental or exceptionally hazardous: it is established, evidence-based, and growing safer and more accessible across India.

Its truest achievement is not simply extending life, but restoring it: another birthday, another child watched growing up, another future reclaimed. For these patients, a transplant is quite literally a chance to begin again.

(Dr. Narendra Agrawal, Hematologist and Bone Marrow Transplant Physician and Senior Consultant and Unit Head of Haemato-Oncology at Rajiv Gandhi Cancer Institute & Research Centre.)