Why am I always thirsty - and what can I do about it?

There has been a huge drive to get people drinking more water in recent years - but how much is too much?

Sales of massive 40-ounce water bottles like Stanleys have surged by more than 80 percent in just four years, totaling more than $750 million.

It comes as part of global campaigns to get people drinking more water - with experts estimating that 50 percent of Americans and Brits don't drink enough.

However, if you find yourself constantly thirsty no matter how many times you refill your water bottle, experts warn it could be a sign of an underlying problem. 

While it could be that you're eating too many salty or sugary foods, or your new meds are making you run to the bathroom more often, excessive thirst could also be a sign of conditions like diabetes and kidney issues. 

Excessive thirst is a sign of dehydration, which could be caused by an unhealthy diet, as well as conditions like diabetes and anemia

Salty snacks, sugary drinks, processed meats, spicy foods, and alcohol can all dehydrate you

Diabetes causes a dry mouth, which could make you drink more.

Diabetes can be detected by your doctor with a simple blood test, so if you're drinking more than eight glasses every day and still not quenching your thirst, it may be prudent to schedule a visit.

The blood test will measure average blood glucose, also known as A1C.

Having 6.5 percent A1C indicates diabetes, and anywhere from 5.7 to 6.4 percent is prediabetes. 

Excessive thirst can also be a sign of kidney issues like nephrogenic diabetes insipidus, which is when the body fails to respond to antidiuretic hormone, also known as ADH. 

This causes the body to make too much urine, which requires you to drink more water to stay hydrated. 

So if you find yourself drinking the same amount of liquid as your colleagues or friends, yet needing to use the bathroom a lot more, it could be ADH. 

Other signs of nephrogenic diabetes insipidus include dry mouth, fatigue, and dizziness.  

The condition is typically diagnosed with blood tests, urine tests, and a water deprivation test, which measures urine output after several hours of not drinking any water. 

Ashley Summers, 35, was a daycare worker and mother of two. She passed away soon after the July 4th holiday from water toxicity or hyponatremia

Hyponatremia is characterized by insufficient levels of sodium in the body, an essential electrolyte that helps to regulate the delicate balance of fluids in cells as well as maintain proper nerve and muscle function. Drinking too much water dilutes concentrations of sodium in the blood

Additionally, thirst can be a sign of anemia, which is when the blood doesn't produce enough healthy red blood cells.

Red blood cells create the protein hemoglobin, which carries oxygen throughout the body. 

Without enough of that oxygen, you're more likely to experience fatigue, weakness, shortness of breath, and headaches, along with dehydration. 

Anemia is typically diagnosed with a routine blood test known as a complete blood count (CBC), which measures the amount of red blood cells in the blood.  

If those conditions are ruled out, it may be time to take a look at your diet. 

Nick Hird, a hydration expert and co-founder of ViDrate, said certain foods could leave you parched.

Secret to anti-aging: Drinking eight glasses of water a day can prolong your life for up to 15 YEARS and slash the risk of heart attacks, strokes, dementia

Adults who stay well-hydrated live years longer and are far less likely to develop chronic health conditions, a major US Government-funded study suggests. 

This includes processed meat, which contains the preservative sodium nitrate to keep it fresh. Similar to salt, it has been linked with an increased chance of dehydration.

'Spicy dishes, while delicious, can stimulate your taste buds and make you sweat,' Mr Hird said. 

Those who drink loads of sugary beverages may also be at risk of excessive thirst, as sugar pulls water from surrounding cells, leading to increased urination. This dehydrates the body. 

Sam Tejada, a functional medicine expert at Liquivida, told DailyMail.com that certain drugs could also be to blame. 

'Some medications, such as diuretics, can increase urine production and lead to dehydration and thirst,' he said.

To keep hydrated, Mr Tejada recommends sticking with the age-old eight glasses of water a day, which is about 64 ounces. However, he noted that people who weigh more or are more active may need to increase that measure. 

The CDC does not offer specific recommendations on how much water to drink. 

Additionally, a study published last year by the National Institutes of Health found that those who drank eight glasses of water a day were less likely to suffer strokes, kidney disease, or heart attacks.

They also increased their lifespans by about 15 years.  

Dr Atil Kargi, an endocrinologist at the University of North Carolina at Chapel Hill, told Fox News that if you're experiencing excessive thirst, try limiting salty, sugary, and spicy foods, and increase water consumption in general.

'If you suspect you may have a medical condition, it's essential to consult a healthcare professional timely for proper evaluation and treatment,' Ms Routhenstein said. 

Michelle Routhenstein, a registered dietitian nutritionist at EntirelyNourished, told DailyMail.com that downing more than one liter of water - about 33 ounces, which is less than one Stanley Quencher - per hour could have its own consequences.

She said that this could lead to water intoxication, also known as hyponatremia. Drinking water increases the amount of it in the blood. However, the kidneys can only filter out about 0.8 to one liter every hour.

Consuming more than that could leave your kidneys unable to keep up, leading to an imbalance of sodium levels. Excess fluids then travel from the utside to the inside of cells, causing them to swell.

Over time, Ms Routhenstein said this leads to side effects like headaches, nausea, and vomiting. More severe cases have been shown to cause drowsiness, muscle weakness, high blood pressure, confusion, difficulty breathing, and kidney failure.

'It's vital to consume water in the adequate amount for you to avoid these health risks,' she said. 

Last year, Indiana mother-of-two Ashley Summers died from water intoxication after she had consumed the equivalent of four 16oz bottles in just 20 minutes.  

'If you have unquenchable thirst, frequent urination, swelling, mental confusion, or persistent symptoms like nausea and headaches, it may indicate a medical issue like diabetes or kidney disease,' Ms Routhenstein said. 

People with diabetes, for example, have too much glucose, also known as sugar, in their bloodstream. This forces the kidneys to go into overdrive to get rid of that extra sugar, which leads to frequent urination. 

Losing water that rapidly causes excess thirst, so a diabetic's brain tells them to drink more.