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

The NHS is urging millions of people across the UK to take vitamin D to support overall health, but experts say certain symptoms should not be ignored. In a post shared on X, an NHS spokesperson said: “From October to March we can’t make enough vitamin D from sunlight, so to keep bones and muscles healthy, it’s best to take a daily 10 microgram supplement of vitamin D. You can get vitamin D from most pharmacies and retailers.”

While health professionals agree that vitamin D supplementation is important for many people, especially during the colder months, they stress that it should be taken carefully.

Why Does Sunlight Matter For Vitamin D Production?

Sunlight plays a crucial role in how the body makes vitamin D. UVB rays trigger a reaction in the skin that converts a compound called 7-dehydrocholesterol into vitamin D3. This form of vitamin D is essential for absorbing calcium, maintaining strong bones, and supporting the immune system.

As sunlight in the UK is not strong enough between autumn and early spring, the government advises everyone to consider taking a daily supplement of 10 micrograms, or 400 IU. Relying on food alone is often not enough to meet daily needs during this period.

Expert Warns Too Much Vitamin D Can Backfire

Biomedical scientist Tobias Mapulanga, who co-founded Repose Healthcare, has warned that some people may be taking more vitamin D than their bodies can handle. He explained that as winter advice circulates, many people add tablets, sprays, or gummies without realising they are doubling up.

He said that symptoms such as constant thirst, needing the toilet more often, nausea, stomach discomfort or constipation, headaches, mental fog, and new aches or cramps can appear soon after increasing vitamin D intake. These signs are often mistaken for winter illnesses, when they may actually point to excess supplementation.

“The message is simple,” he added. “The right dose helps, but taking too much can leave you feeling worse, not better.”

High-Dose Supplements Raise Safety Concerns

Research shows that 42% of UK adults reported taking vitamin D supplements in the past year. However, an investigation by Which? found some vitamin D products on sale contained doses as high as 12.5 times the recommended safe upper limit.

NHS England also logged 42 incidents over a two-year period where high-strength vitamin D was given more often than intended. Some of these cases led to hospital treatment for hypercalcaemia, a condition caused by too much calcium in the blood, according to reports from Bristol Live.

Stop Taking Vitamin D If You Notice These Warning Signs

1. Ongoing thirst and frequent trips to the toilet

If you suddenly feel unusually thirsty or find yourself urinating more often after starting vitamin D, it may be a sign you’re overdoing it. Cut back to a single 10 microgram tablet and stop using any additional vitamin D products if this happens.

Too much vitamin D can disrupt fluid and salt balance in the body, leaving you dehydrated and running to the bathroom. Check labels carefully and remove multivitamins, sprays, gummies, and fortified foods or drinks that also contain vitamin D.

Keep water close by and sip regularly while your body settles. Stay well below the upper limit of 100 micrograms, keep just one product visible, and put the rest out of sight to avoid accidental doubling.

2. Nausea, excessive burping, or stomach discomfort

Feeling sick, bloated, or dealing with an upset stomach after taking vitamin D suggests it isn’t agreeing with you. Try taking your supplement with a full meal and switch from sprays or gummies to a plain D3 tablet if symptoms persist.

Food helps protect the stomach lining, while sprays and gummies often contain sweeteners or flavourings that can irritate digestion. Choose a simple cholecalciferol tablet with minimal ingredients and reduce the dose to 10 micrograms.

Avoid fortified shakes or energy drinks until your stomach feels normal again.

3. New muscle cramps or bone aches

If you notice more aches in your bones or frequent muscle cramps after starting vitamin D, take it as a signal to reassess. Lower your dose and focus on staying well hydrated while eating mineral-rich foods.

Excess vitamin D can interfere with mineral balance, which muscles rely on, and dehydration can make cramping worse. Drink water with meals and include yoghurt, leafy greens, beans, and bananas in your diet.

Gentle stretching and short walks can ease stiffness. Stick to one 10 microgram supplement and avoid adding anything else until symptoms improve.

4. Brain fog or headaches

Trouble concentrating or recurring headaches can be signs that your vitamin D intake is too high. Replace multivitamins or high-strength products with a single 10 microgram D3 tablet.

High doses can raise calcium levels, and extra additives found in combined supplements may affect clarity of thought. Choose a product that contains only cholecalciferol and basic fillers.

Take it with food at the same time each day for consistency and better digestion. Avoid combined vitamin A and D products and focus on one simple supplement.

To prevent accidental overuse, review everything you take that contains vitamin D. Spread out all tablets, sprays, gummies, and fortified foods, and read each label carefully. Convert IU to micrograms by dividing by 40 to make totals easier to track.

Discard any extras and stick to one daily 10 microgram source. Keep a note of symptoms such as thirst, frequent urination, stomach upset, cramps, or mental fog to see how they relate to your intake.

For decades, iodine deficiency was a serious public health concern in India. Conditions like goitre and other iodine-related disorders were widespread until the nationwide introduction of iodised salt changed the picture. The move is widely seen as a major health success, preventing thyroid problems on a large scale.

Due to this, iodine has come to be almost inseparable from conversations around thyroid health. While its role is vital, doctors now caution that focusing on iodine alone can give a false sense of security.

“The thyroid is often misunderstood as a simple gland that switches on with iodine,” says Dr. Narendra BS, Lead Consultant – Endocrinology and Diabetology at Aster Whitefield. “In reality, it is a complex hormone-producing system that depends on several nutrients and physiological processes working together.”

Thyroid Does Not Run On Iodine Alone

The thyroid gland produces hormones that regulate metabolism, energy levels, body temperature, and even mood. Iodine is required to make these hormones, but it is only one step in a longer chain.

According to Dr. Narendra, problems can still arise even when iodine intake is adequate. “Hormone production and activation involve multiple stages. If other nutrients are lacking or the body is under stress, thyroid function can suffer despite normal iodine consumption,” he explains.

Nutrients That Quietly Support Thyroid Function

Several nutrients play supporting roles in keeping the thyroid healthy. Selenium is needed to activate thyroid hormones into their usable form. Iron is essential for hormone production itself, which is why thyroid disorders and anaemia often occur together. Zinc contributes to hormone synthesis, while adequate protein levels help transport thyroid hormones through the bloodstream.

“When these nutrients are missing, patients may continue to experience symptoms even though they are using iodised salt regularly,” Dr. Narendra notes.

Diet Patterns Matter More

Modern eating habits can also place strain on the thyroid. Very restrictive diets, frequent meal skipping, or cutting out entire food groups can disrupt hormonal balance. Diets heavy in ultra-processed foods may increase inflammation and worsen overall metabolic health, indirectly affecting thyroid function.

“A varied, balanced diet supports not just the thyroid, but the entire endocrine system,” says Dr. Narendra. “Nutrition should be looked at as a whole, not reduced to a single nutrient.”

Lifestyle factors often overlooked in thyroid care include stress and sleep. Chronic stress and poor sleep quality can interfere with how thyroid hormones are converted and used in the body.

“This is why some people feel unwell despite having ‘normal’ thyroid blood test results,” Dr. Narendra explains. “Stress hormones can mask or worsen symptoms, making the problem harder to identify if we focus only on iodine levels.”

When Salt Alone Is Not The Solution

Many people turn to iodised salt hoping it will ease fatigue, weight gain, or hair loss. While correcting iodine deficiency is important, these symptoms are frequently linked to broader thyroid disorders, including autoimmune conditions, which require medical evaluation and proper treatment.

“Iodised salt prevents iodine deficiency, but it cannot correct poor diet, chronic stress, sleep deprivation, or undiagnosed thyroid disease,” Dr. Narendra cautions.

Iodised salt is a starting point, not a complete solution. It plays a crucial role in preventing iodine deficiency, but true thyroid health depends on balanced nutrition, healthy habits, and timely medical care. The thyroid needs more than what comes from the saltshaker to function well.

A pharmacist has warned that people taking certain long-term medications should stay alert to subtle symptoms such as numbness, tingling, and an unusually red or sore tongue. According to Superdrug Pharmacy Superintendent Niamh McMillan, as per Mirror, the signs are often easy to dismiss and may quietly develop over time in people with low vitamin B12 levels.

Pharmacist Warns Certain Medicines May Trigger Overlooked Vitamin B12 Symptoms

McMillan explained that vitamin B12 plays a vital role in keeping nerves and blood cells healthy. A shortage can build up slowly, which means early symptoms are often brushed aside or mistaken for everyday fatigue.

She said common warning signs include persistent tiredness or weakness, breathlessness, headaches, dizziness, pale skin, and a sore or red tongue. Some people may also notice pins and needles or numbness in their hands or feet, memory lapses, trouble focusing, or changes in mood such as feeling low or unusually irritable.

Who Is Most At Risk Of Low B12 Levels?

Vitamin B12 deficiency occurs when the body either does not get enough of the vitamin from food or struggles to absorb it properly. McMillan noted that people following vegetarian or vegan diets are at higher risk, as B12 is naturally found mainly in animal products.

Older adults are also more vulnerable, as are people with digestive conditions such as coeliac disease or Crohn’s disease. In addition, those taking certain medications may be affected, particularly long-term acid-reducing drugs such as proton pump inhibitors or diabetes medication like metformin.

Dietary Sources That Help Maintain B12 Levels

To reduce the risk of deficiency, McMillan advised including reliable dietary sources of vitamin B12 wherever possible. Foods naturally rich in the vitamin include meat, fish, eggs, milk, cheese, and yoghurt.

For people who avoid animal products, fortified foods such as some breakfast cereals and plant-based milks can help support intake. In some cases, supplements may also be useful, especially when diet alone is not enough or absorption is impaired.

When To Seek Medical Advice?

McMillan stressed that anyone experiencing symptoms or falling into a higher-risk group should speak to a healthcare professional. A simple blood test can measure B12 levels, and early treatment can help prevent lasting nerve damage or other complications.

She added that Superdrug Health Clinics offer a Vitamin B12 Injection Service at selected UK locations, following clinical assessment or confirmation of deficiency.

How Medications Can Interfere With Vitamin B12?

Several commonly prescribed medications can affect how the body absorbs or uses vitamin B12. This often happens because the drugs alter conditions in the stomach or gut, making it harder for B12 to be released from food or absorbed into the bloodstream.

Medications Linked to Vitamin B12 Deficiency

The most frequently associated medications include:

• Proton Pump Inhibitors (PPIs): such as omeprazole, esomeprazole, and lansoprazole
• H2 Blockers: including famotidine and cimetidine
• Metformin
• Oral contraceptives, although experts continue to debate whether these cause a true deficiency
• Colchicine, used to treat gout and known to damage the intestinal lining
• Anticonvulsants, including drugs like phenytoin and phenobarbital, which can affect B-vitamin metabolism
• Nitrous oxide, commonly known as laughing gas, which can rapidly inactivate existing B12 in the body
• Antibiotics, particularly long-term use of chloramphenicol or neomycin, which can disrupt gut bacteria involved in B12 processing

What To Do If You Take These Medications Long Term?

Experts advise people on these medicines not to stop treatment without medical guidance. Instead, they recommend staying alert for symptoms such as fatigue, tingling or numbness in the hands or feet, brain fog, or a sore, red tongue.

Getting tested is also key. A straightforward blood test can confirm B12 levels, and many doctors now suggest regular screening for patients who take metformin or proton pump inhibitors over extended periods.