Article edited for scientific accuracy by Illuminate Labs Blog Editor Taylor Graber MD
With many health sites publishing recommendations for water intake per day, usually measured in cups, consumers are often confused about how to determine if they’re getting enough water. The fact that water bottles also have different sizes, and many don’t publish a Nutrition Facts label, can make it challenging to ensure you're staying properly hydrated.
Generally the health recommendations for a specific number of cups of water per day are unscientific, just like the recent concerns over calories in toothpaste, and the body can dictate ideal water intake from thirst.
In this article we’ll break down how many cups are in some of the most popular bottled water products, since it varies by product.
Most bottled water is measured in ounces, and 1 oz = 0.125 cups.
Standard glass of water (8 oz) - 1 cup
Essentia - 2.5 cups
Core - 3.8 cups
LIFEWTR - 2.1 cups
Flow - 4.2 cups
Fiji (regular size) - 2.1 cups
Certain brands like Poland Spring, SmartWater and Evian sell so many variations of water bottles that we can’t provide a general answer.
Since you have the formula above, all you need to do is multiply your water bottle’s ounces number by 0.125 to get the number of cups.
Why We Don’t Recommend Bottled Water
Bottled water is not only bad for the environment because of the single-use plastic, but it may also be more harmful than filtered or tap water because there are lax regulations on certain contaminant levels, like heavy metals, in the U.S. for bottled water. There are also no regulations on allowable microplastics levels, and these hormone-disrupting chemicals are significantly more common in bottled water than tap according to medical research.
Better alternatives to bottled water include tap water (depending on location) and filtered water using a system like the Berkey which removes a large amount of toxins and environmental contaminants.