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

She came to the hospital because of a cough that would not go away. The cough was eventually found to be nothing serious. But her CT scan revealed something unexpected — a 12 mm nodule in the outer part of her right lung.

She had never smoked. She felt completely well.

Yet that tiny shadow raised a big question: was it an old tuberculosis scar, a harmless growth, or an early lung cancer?

A CT scan can show us that a nodule is there. It cannot always tell us what it is.

This is an increasingly familiar situation. As CT scans have become more widely used, particularly after the COVID-19 pandemic, doctors are finding small lung nodules in people being scanned for entirely different reasons. Most turn out to be benign. Some, however, need closer assessment.

India has another challenge. Tuberculosis and its scars are common, and a lung shadow can sometimes be attributed to TB without tissue confirmation. While treating tuberculosis promptly is important, assuming that every suspicious nodule is TB can occasionally delay the diagnosis of something else, including cancer.

The answer, when appropriate, is to obtain a tissue sample.

Traditionally, a small nodule deep in the lung could be difficult to reach. A needle biopsy through the chest can be effective but carries a risk of a collapsed lung. Conventional bronchoscopy is excellent for the larger airways but becomes more challenging as the target gets smaller and farther towards the edge of the lung. Surgery may sometimes be necessary.

Newer techniques are changing the picture.

Navigation bronchoscopy uses the patient's CT scan to create a three-dimensional map of the airways and guide a thin catheter towards the nodule. Cone Beam CT adds real-time three-dimensional imaging during the procedure, allowing the doctor to check where the instruments are in relation to the lesion before taking the biopsy.

In simple terms, navigation helps us find the way; Cone Beam CT helps us confirm we are there.

The tissue can then be examined immediately where appropriate, helping determine whether the sample is adequate and whether additional material is needed for advanced testing.

Importantly, not every nodule needs a biopsy. Many are best managed through carefully planned follow-up scans. The decision depends on the nodule's size and appearance, previous scans, and the patient's overall risk.

For patients, the message is reassuring: a lung nodule does not mean cancer. But it should not be ignored either.

Keep previous scans. Ask what the likely possibilities are. Understand why your doctor recommends surveillance or biopsy — and make sure the follow-up happens.

Today, advanced bronchoscopy is helping doctors turn a worrying shadow into something much more useful: an answer.

(By Dr Shyam Krishnan, Intervention Pulmonologist, CMRI)

Second-hand smoke increases the risk of lung cancer in people who have never smoked because it contains harmful chemicals, including known cancer-causing agents. When someone who does not smoke is around a person who is smoking they breathe in smoke from the burning cigarette and the smoke that the smoker breathes out. This mix of smoke is called second-hand smoke or environmental tobacco smoke.

How Second-Hand Smoke Damages Lung Cells And DNA

Also read: From Occasional to Long-Term Smoking, Experts Explain How Much Lung Damage Can Actually Reverse After Quitting?

Even though the non-smoker does not light a cigarette they still take in dangerous substances. These chemicals can irritate the lungs. Cause inflammation. They also create stress, which means the body’s natural defenses are overwhelmed by harmful molecules. Over time this damage can harm the DNA inside lung cells.

When DNA is damaged the cells may start to change in ways. These abnormal cells can grow out of control. Turn into cancer. The longer and more intense the exposure to second-hand smoke the higher the risk becomes. For example, people who live with a smoker or work in places where smoking is allowed may get exposure over time.

Second-hand smoke also makes it harder for the body to fix cells. It keeps the lungs in a state of inflammation. This ongoing irritation helps create a condition where cancer can start and grow.

There is no level of exposure to tobacco smoke. Even small amounts can add to the risk. Some people are especially at risk like children, pregnant women and those with asthma or other breathing problems.

How Can Non-Smokers Reduce Their Exposure?

The best way to prevent lung cancer from second-hand smoke is to reduce exposure. This means keeping homes, cars and workplaces completely smoke-free. It also means supporting smoke- policies and encouraging people to quit smoking. Protecting non-smokers from second-hand smoke is a step, in reducing lung cancer rates.

Dr Saket Kumar, Senior Consultant – Physician & Pulmonology, Sterling Hospitals, Bhayli, Vadodara

Dry cough and breathing difficulty aren’t always caused by asthma, COPD, or infections. They can also be signs of interstitial lung disease (ILD), a group of lung conditions that can cause inflammation and scarring and, in some cases, progressive loss of lung function.

ILD can go unnoticed in its early stages because its symptoms are often mistaken for more common respiratory conditions. By the time a patient undergoes a CT scan and reaches an ILD clinic, significant lung scarring may have already developed — and some of that damage may be irreversible.

Millions May Be Living With ILD Worldwide

A Global Burden of Disease Study 2023 analysis, published in December 2025, estimated that 4.58 million people were living with ILD and pulmonary sarcoidosis worldwide in 2023, with 112,650 deaths attributed to the conditions that year.

“The true global burden of ILD is higher than currently reported, particularly in underserved populations and low- and middle-income countries,” Prof. Marlies Wijsenbeek-Lourens, Pulmonologist and Head of the Center for Interstitial Lung Diseases and Sarcoidosis at Erasmus University Medical Center, Netherlands, told HealthandMe.

The global expert said most available epidemiological data come from Europe, North America, Japan, South Korea and Australia, where access to specialist care, multidisciplinary diagnosis and high-resolution CT imaging is generally more available.

“As a result, large parts of Africa, South America, South and Southeast Asia remain underrepresented in current estimates. In these regions, more limited access to diagnostic facilities, fewer ILD specialists and under-recognition of disease undoubtedly result in substantial underdiagnosis.”

Even in high-income countries, she added, some patients with ILD likely remain undiagnosed because symptoms such as breathlessness and cough are often attributed to more common conditions.

Also read: From Occasional to Long-Term Smoking, Experts Explain How Much Lung Damage Can Actually Reverse After Quitting?

What Is Interstitial Lung Disease?

ILD is not a single disease but a group of more than 200 lung conditions. The disease affects the interstitium, the tissue surrounding and supporting the lungs’ air sacs, or alveoli. In ILD, this tissue can become inflamed and/or scarred.

As scarring progresses, the lungs can become stiffer, making it harder for them to expand and reducing the efficiency of oxygen transfer. As the disease progresses, the lung shrinks, making it difficult for the patient to breathe.

According to Prof. Marlies, there is a rise in ILD diagnoses due to several factors, such as:

• Better awareness
• More HRCT scans
• Better diagnosis
• Ageing populations
• Autoimmune disease
• Environmental and occupational exposure.

When Should Doctors Suspect ILD?

Some forms of ILD can be treated more effectively when identified early, before permanent lung damage occurs.

“Unfortunately, many patients still reach an ILD specialist late. Breathlessness and cough may initially be treated as asthma, infection or sometimes even tuberculosis. By the time a CT scan is done and the patient reaches an ILD clinic, significant scarring may already have developed,” Dr Asmita Mehta, Professor and Head, Department of Respiratory Medicine at Amrita Institute of Medical Sciences, Kochi, told HealthandMe.

“A dry cough and gradually progressive breathlessness lasting for more than three months, particularly breathlessness while walking or climbing stairs, should raise suspicion of ILD rather than simply being attributed to asthma, infection or ageing,” she added.

Read More: US Cancer Death Rates Fall For Men, Women: Lung Cancer Progress Drives Decline

Doctors should think of ILD especially when these symptoms do not improve with usual treatment, when fine crackling sounds are heard in the lungs, or when oxygen levels fall during walking.

It is also important to ask about joint pain, skin changes, dry eyes or mouth, and exposure to birds, mould, biomass smoke or occupational dust. Sometimes the clue to ILD is outside the lungs, the expert said.

ILD And COVID-19

Pre-existing ILD was associated with worse outcomes during COVID-19. Now, six years later, some patients who had severe COVID-19 also continue to show persistent lung abnormalities.

“The reassuring part is that not every abnormal CT after COVID means progressive lung fibrosis. In many patients, the lung changes gradually improve or remain stable. Some patients who had very severe COVID, prolonged ICU admission, or required ventilation may be left with persistent scarring and may need longer follow-up,” Dr Asmita said.

What Does ILD Look Like In India?

Common ILD diagnoses seen in India include connective tissue disease-associated ILD (CTD-ILD), hypersensitivity pneumonitis (HP), idiopathic pulmonary fibrosis (IPF), sarcoidosis and idiopathic nonspecific interstitial pneumonia (NSIP).

Dr Asmita said that, apart from idiopathic pulmonary fibrosis, ILD related to autoimmune diseases and environmental exposures is also commonly seen in India. These exposures can include birds, mould, biomass smoke and certain occupations.

Epidemiological reviews estimate the overall prevalence of ILD in India to range between 49.0 and 98.1 per 100,000 people, with an annual crude incidence rate of 10.1 to 20.2 per 100,000 population.

India is also building a larger national evidence base through the ICMR-led Indian Network of Pulmonary Fibrosis (INPF) registry.

Biggest Challenges For ILD Patients In India

• Delayed diagnosis: Symptoms can be mistaken for asthma, infections, or tuberculosis.
• Limited specialist access: ILD specialists and advanced diagnostic facilities are concentrated in larger centres.
• High treatment costs: Medicines, investigations, oxygen, and pulmonary rehabilitation can be expensive.
• Limited transplant access: Lung transplantation remains available only to a limited number of eligible patients.
• Low awareness: Many patients and families are unfamiliar with ILD and its long-term nature.

“We therefore need not only earlier diagnosis, but better awareness, affordable treatment, wider access to ILD specialists and stronger advanced-care and transplant programs,” Dr Asmita said.