The amount of water that is safe to drink a day is between 2 liters to 2.5 liters a day for most people.
Although it can also vary from person to person and some people can drink more than that and others should not drink any more than 2 to 2.5 liters of water a day.
Drinking more than the recommended amount of water per day can cause you to have very low levels of salt and other important electrolytes that your body needs.
So, while it's important to drink enough water and stay hydrated, you don't want to consume more than 2 liters to 2.5 liters of water a day.
And consuming way too much water a day could lead to water intoxication, which can be fatal.
1 gallon of water would be 3.785 liters of water, which is considered too much in a day.
Although if you're sweating a lot and you slowly drink that water through the day, then a gallon of water a day may not be bad or everyone.
There's no real standard amount of water a person should drink daily, as it varies from person to person and depends on your activity levels and health conditions.
Although the National Academy of Medicine also estimates that a persons optimal daily fluid intake is around 15 cups of fluids for healthy men and 11 cups of fluid for healthy women.
If you have kidney disease, kidney failure or other kidney issues, then you may need to drink less water per day as your kidneys are not able to filter out the water in the body.
If you suspect that you may be overhydrated, you should look for symptoms of overhydration, like nausea and vomiting, cloudy thinking, muscle weakness, spasms or cramps and even headaches.
And in severe cases of overhydration, it can cause symptoms like seizures, mental confusion, unconsciousness and even a coma and sometimes death.
When drinking water it's also better to sip the water instead of chug it.
The bare minimum amount of water for survival is 1 liter of water per day, but this is only for resting in mild conditions and your needs of water increase when it's hot out, with activity and altitude.
Some recommend that you need 2 to 3 liters of water for basic function and much more for strenuous activity, as dehydration can become life threatening very quickly, with most people surviving only around 3 days without water.