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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.
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.
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:
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.
Water intoxication is rare, but certain scenarios can increase the risk:
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.
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.
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.
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.
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.
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:
Older adults, whose thirst mechanisms may decline with age, should be proactive about maintaining hydration, especially during illness or hot weather.
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.
To avoid the dangers of overhydration:
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
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Anxiety and depression are major concerns in adulthood, but could nutrition during the earliest stages of life influence health decades later? Two new studies suggest that lower sugar exposure during the first 1,000 days of life may be associated with lower risks of anxiety, depression and even several cancers later in life.
The findings, from studies published in Translational Psychiatry and PNAS point to the potential long-term effects of early-life nutrition. However, the findings do not mean that restricting sugar in infancy directly prevents these diseases.
A 2026 study led by researchers from the University of Surrey, UK, analyzed 46,448 people born between October 1951 and March 1956.
Participants were grouped according to how long they were exposed to sugar rationing: from in utero only to 24 months. People conceived after food rationing had ended served as the main comparison group.
Researchers also analyzed brain MRI data from 5,990 participants.
Compared with people conceived after rationing ended, those exposed to sugar rationing for the three longest periods had significantly lower hazards of both anxiety and depression.
When later-life sugar intake was considered, the association with anxiety persisted among those exposed throughout pregnancy and the first two years of life, while the association with depression weakened and was no longer statistically significant.
Further, MRI analysis found differences across rationing groups in 80 of 139 gray matter regions. Analysis identified 11 regions that differed from participants conceived immediately after rationing ended, including the brainstem, occipital fusiform gyrus and several cerebellar regions.
A separate study published in PNAS examined whether sugar exposure during the first 1,000 days could influence cancer risk later in life.
Researchers from China Agricultural University and the University of Cambridge used the abrupt end of UK sugar rationing in September 1953 as a natural experiment. The analysis included 64,761 UK Biobank participants born between 1951 and 1956.
Compared with those whose first 1,000 days were not affected by rationing, participants exposed to rationing showed lower incidence of several cancers:
The researchers identified two possible pathways behind the association.
Sugar is an important source of energy for the brain, and very low blood glucose can impair brain function. However, excess sugar intake has also been associated with metabolic problems that can affect long-term health.
When it comes to cancer, sugar does not directly cause cancer, and cutting out all sugar does not “starve” cancer cells. Both healthy and cancer cells use glucose for energy.
However, consistently consuming excessive amounts of added sugar can contribute to weight gain and obesity, which are established risk factors for several cancers.
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Men who consume higher amounts of dietary nitrite may have a greater risk of colorectal cancer, particularly the type affecting the distal colon, according to a new study published in the Journal of the National Cancer Institute.
The study followed 82,009 middle-aged and older adults in Sweden for more than two decades and identified 3,170 cases of colorectal cancer.
Researchers found that men in the highest category of nitrite intake had a 23% higher risk of colorectal cancer overall compared with those in the lowest category. The strongest association was for for distal colon cancer, where the risk was 50% higher.
The findings were not seen in women, and dietary nitrate was not associated with colorectal cancer in either men or women.
Researchers from Karolinska Institutet in Sweden used dietary information collected in 1997 and updated in 2009 and 2019. They linked this information with Sweden's cancer registry to identify colorectal cancer cases through 2022.
Rather than relying only on participants' diet at the beginning of the study, researchers used repeated measurements to capture changes in nitrite and nitrate intake over time. Among men, the highest versus lowest levels of nitrite consumption were associated with a hazard ratio of 1.23 for colorectal cancer. For distal colon cancer, the hazard ratio rose to 1.50.
Also read: How Genetic and Genomic Testing Can Help Women Make Smarter Cancer Decisions
Nitrite and nitrate are related compounds, but they are found in different foods and behave differently in the body. Nitrate occurs naturally in vegetables, particularly leafy greens, as well as drinking water. Nitrite is also naturally present in some foods but is commonly used as a preservative in processed meat and other animal products.
The researchers found no association between dietary nitrate and colorectal cancer, making the distinction particularly important.
Also read: Moderna-Merck’s Personalized mRNA Vaccine: Ushering In A New Era In Cancer Care?
A possible explanation involves N-nitroso compounds, which can form when nitrate and nitrite undergo chemical reactions in the body. Some N-nitroso compounds are known to be carcinogenic in animals.
The researchers saw that previous studies have also investigated possible links between nitrite exposure and cancers of the gastrointestinal tract. However, the exact biological mechanism behind the association observed in this study remains uncertain.
The researchers also found that the association was specific to men, and they said the reason for this difference is unclear.
The authors noted that the higher risk associated with nitrite intake was confined to men and suggested several possible biological explanations, including differences in oxidative stress and other sex-specific factors.
But they stressed that these mechanisms have not been established as the reason for the finding. The study concludes that further research should examine nitrite and colorectal cancer separately in men and women and.
The study was observational, meaning researchers identified an association between dietary nitrite intake and cancer risk but could not prove a direct cause and effect relationship.
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For people who work, laptops and computers are something we use every day. Sitting in front of a screen for hours can be bad for your neck and spine. When you sit and use your laptop the way you position yourself can hurt your neck over time.
This is true even when you are just scrolling on your phone. Keeping your head bent for a long time can put stress on the muscles and joints in your neck.
The problem is not the laptop itself but how we use it. Many people spend hours looking down at a screen without realizing it. This can cause muscle fatigue, stiffness, headaches and neck pain that will not go away.
Your neck is meant to support your head and let you move it around. When you keep your head tilted forward for hours the muscles in your neck have to work hard to keep it that way. Over time this can cause discomfort. Make it harder to move your neck.
If you sit with posture it can also affect the normal curve of your neck. Poor posture may not cause spinal problems on its own but it can cause wear and discomfort. This is especially true for people who already have neck or spine problems.
Also read: The Hidden Health Risk of Sitting for Long Hours: What Young Professionals Need to Know
One simple way to reduce strain on your neck is to make your workspace more comfortable. Your laptop or monitor should be at eye level so you do not have to look down all the time. Your back should be. Your arms should be comfortable too. Keep your feet flat on the floor. Do not sit still for too long.
It is also important to move regularly. Of sitting for hours get up and move every 30-40 minutes. Stand up walk around and move your neck and shoulders gently. This can help prevent stiffness and reduce strain on your neck. Your neck is meant to move not be stuck in one position for hours.
If your neck is stiff after a day, it may feel better with rest and better posture. If the pain gets worse or does not go away, you should see a doctor. If you have pain in your arm or if your arm feels numb tingling or weak you should see a doctor too.
To protect your neck, you do not have to make changes. Just make small adjustments to how you sit and use your laptop and move around more during the day. This can make using your laptop more comfortable. Reduce strain, on your neck and spine.
By Dr. Zahir Abbas Merchant, Consultant Spine Surgeon, Saifee Hospital, Mumbai
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