Looking Back on Our Emails, other requests and published worldwide queries, the most common question being asked by the internet community about drinking water appears to be: How much water should I drink every day?  

1. How much water do I actually need daily?

This is the clear #1. The old “8 glasses (about 2 liters) a day” rule is widely repeated but not strictly evidence-based for everyone. Guidelines from groups like the National Academies of Sciences often suggest roughly 3.7 liters (about 15.5 cups) of total fluids per day for men and 2.7 liters (about 11.5 cups) for women and this is total fluids per day that includes water, food and other beverages.   For most individuals about 20% to 30 % of your daily hydration need comes from food.    As an individual that has always struggled with weight, I like to remind you that sometimes when you feel hungry, your body is actually thirsty. 

2. Is the “8 glasses a day” rule real / a myth?

Many sources recommend the 8x8 rule (The 8x8 rule suggests that adults should drink eight 8-ounce glasses of water per day, totaling about 2 liters.)*  The amount of fluids you need is also a function of age, health, job or activity/ activity level, climate, condition, and body type.  We suggest a good old trail and error analysis. 

There are sources that suggest that the 8x8 rule was the result of a 1945 U.S. Food and Nutrition Board recommendation that suggested that "1 mL of water should be consumed for every calorie consumed". This means a 2,000-calorie diet would require the consumption of  2 liters, or about 8 glasses.   (Fact/Fiction??)  

Total daily water (from all sources, including food) for adults:

• Sedentary adult male: 3.7 L (about 125 oz)
• Sedentary adult female: 2.7 L (about 91 oz)
• Active adults: Add 0.5–1 L per hour of exercise
• Hot climates: Add 0.5–1 L

3. Can you drink too much water?

Yes, though it’s rare in healthy people. Excessive intake in a short time can lead to water intoxication (hyponatremia), diluting blood sodium levels. It’s more a risk in extreme cases like endurance events or contests. The body usually handles surplus via urine.

4. What are the signs of dehydration (and how do I know if I’m getting enough)?

Common indicators: thirst, dark yellow urine, fatigue, headaches, dry mouth/skin, irritability, or reduced concentration. Pale straw-colored urine and infrequent strong thirst are good signs of adequate hydration. Mild dehydration can affect mood, energy, and cognitive function.

The Best Hydration Indicator - Check Your Urine !

Urine color is the most practical real-time gauge:

• Clear or very pale yellow: Well-hydrated, possibly over-hydrated.
• Pale yellow: Optimal.
• Medium yellow: Slightly dehydrated.
• Dark yellow or amber: Dehydrated.

5. What are the health benefits of drinking more water?

People often ask about weight loss, clearer skin, better energy, digestion, kidney stone prevention, fewer UTIs, headache relief, and overall organ function. Water supports temperature regulation, nutrient transport, joint lubrication, waste removal, and more. Evidence is stronger for some benefits (e.g., kidney stones, certain weight-management contexts) than others; it’s essential but not a miracle cure-all.

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6. Is tap water safe / better or worse than bottled water?

Safety depends on many factors, but normally water from a community water supply system (tap water) is most likely the safer source of drinking water and it is commonly the most monitored and regulated source of drinking water.   In fact, tap water may also be the cheapest source of drinking water.   Other sources may include bottled water, well water, spring water, and even as cistern.   Reading the question is tap water better than bottled water, I would first say that in many cases a lot of bottled water is just purified tap water, but there are some premium bottled water sources that utilize spring water.  From my personal perspective, a spring water source, especially a source with a low total dissolved solids, can be an excellent source of drinking water.  Our suggest would be to check the label on the bottled water or make the equivalent of bottled water at home.  (Go Bottleless and Get Your Drinking Water Tested (City Water or Tap Water) / (Well Water)

7. Do other drinks (coffee, tea, juice, soda, sparkling water) count toward hydration?

Yes other fluids do contribute to the hydration need, but , water is the ideal source, i.e.,  calorie-free, no additives. Caffeinated drinks count for most people in moderate amounts; alcohol is more dehydrating. Food (fruits, veggies, soups) also supplies significant water and again food can contribute from 20 to 30 % of your hydration need.

8. Should I drink alkaline water, distilled water, or other specialty types? Does temperature or timing matter (e.g., first thing in the morning)?

Alkaline water has limited proven benefits for healthy people beyond possibly encouraging more intake. Distilled lacks minerals and may have an off taste.  For my preference, I like Cold water vs. room-temp water, I think that is because the water may have a higher gas content and I like cold water with ice and lemon and sometimes some lime or fruit.  On site website I save  the following: "A cup of coffee contributes about 95% as much hydration as a cup of water."   It appears to be true, because coffee is about 95 % water and 5% coffee, but on other sites have have seen ranges for 95 to 98 % for coffee and teas. 

Know what’s in your water before you drink it. Our Drinking Water Guide for Well Water & City Water is a practical reference for homeowners, renters, and anyone who wants to make informed decisions about their drinking water. Order your copy →

Other Articles

Dry Skin & Dehydrated Skin: How Your Drinking Water Affects Hydration

Allergic to Water, Drinking Water or the Tap Water? Mystery of Aquagenic Urticaria

Can Drinking More Water Help You Lose Weight? The Science

Drinking Water and Health - Is Water Part of the Cure?

Water and Your Pets: Be A Responsible Pet Owner and Get Your Pets On Board

Citations 

How Much Water Do You Need? • The Nutrition Source
https://nutritionsource.hsph.harvard.edu/water/

World’s Most Asked Questions: How Much Water Should I Drink a Day? (SciShow / YouTube)
https://www.youtube.com/watch?v=oW6UI_d98Yw

Other Websites

Know Your H20
B.F. Environmental Consultants
Carbon County Groundwater Guardians
Keystone Clean Water Team (Donate)

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