Wondering Just How Much Water Should You Drink a Day?

image water drink day

So how much water should you drink a day?

This is a tough question to answer, as there are several authoritative bodies out there offering differing advice.

We've all heard the “8 cups a day” rule since we were children. But is that enough?

Every day, we lose liters of water as our metabolism processes the food we eat and the liver and kidneys work to eliminate toxins from our body.

Even if you're the sedentary sort, you're still losing plenty of water-weight through the very unavoidable act of breathing.

Have you ever watched how your breath condensates in the air on a cold day? That's water vapor (ie., steam) escaping your body. This water loss is constantly occurring, it's just that most of us don't see it until the temperature drops to near freezing temperatures.

Table of contents

  1. Current Recommendations for Water Intake
  2. How to Calculate Your Daily Water Needs
  3. Alternative Method for Calculating Water Needs
  4. Rounding Things Up
  5. Always Adjust for the Environment and Exercise Levels
  6. Drink up!

Current Recommendations for Water Intake

The MayoClinic recommends men drink 13, 8-ounce cups a day to stay hydrated, in addition to the water-rich foods they drink.

For women, they recommend 9, 8-ounce cups in addition to water-rich foods they consume like fruits and vegetables.

How to Calculate Your Daily Water Needs

There are so many methods that are espoused in the fitness, health and wellness communities that it can get pretty overwhelming for the average person to calculate their daily hydration needs.

One of the simplest and effective methods is to take your body weight in pounds and multiply that number by 0.5 to determine how much water should you drink a day. The number you come out with will be your daily H20 requirements in ounces.

Here's the bodyweight calculation:

Bodyweight x 0.5 = Daily Fluid Requirement (in ounces).

And here's an example of this calculation for a female who weighs 120 pounds:

120 x 0.5 = 60 ounces or 7.5 cups of water.

image drinking water infographic jpg

Alternative Method for Calculating Water Needs

Another way of determining how much water should you drink a day is to consume 0.034 ounces of water for every calorie you take in. This is very popular among bodybuilders and athletes who need to consume much more calories than are recommended for average people to maintain a healthy bodyweight. While this method is considered a little over-the-top by many, it's yet another great and acceptable way to make sure you're getting enough water into your body to maintain proper levels.

Here's the calculation for the calorie-per-ounce method:

Calories Consumed x 0.034 = Daily Fluid Requirements (in ounces).

And here's an example for a man weighing 175 pounds who consumes 2,000 calories per day:

2,000 x 0.034 = 68 ounces or 8.5 cups of water.

Rounding Things Up

Though the above methods will both ensure adequate hydration, don't fall victim to using a measuring cup. It's perfectly fine to round up!

Moreover, it's important that you adjust your intake for environmental conditions and physical activity. Don't wait until you start feeling thirsty on a hot day before you decide to seek out a fine bottle of spring or mineral water to quench your thirst.

Always Adjust for the Environment and Exercise Levels

If you live and/or work in a hot or cold environment, you'll need plenty more water to stay hydrated.

For most of us, drinking more on hot days makes perfect sense...

However, don't assume that just because you're in a really cold environment and not “sweating” that you need less water. Your metabolism is working overtime to keep the body warm. And you're still sweating, you just can't see or feel it because the cold and wind are literally pulling the moisture from your skin.

First, make sure to get the minimum amounts described above, using the MayoClinic guidelines or by using the ounces-per-bodyweight or onces-per-calories equations. Then feel free to double the amount you come up with, or just make sure you have a couple of extra liters of water on hand and drink continuously.

A mouthful of water every 10 minutes or so can really add up to big water consumption by the end of day and ensure you never push your dehydration boundaries.

Drink up!

When it comes to determining how much water should you drink a day, it's better to play it safe than sorry. Don't be afraid to drink more than your daily allotment. It's perfectly safe to drink 2 – 3 cups more than that which is recommended without incurring any side effects.

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