Is Drinking
Purified Water
Pointless?
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The full narration of the video.
A viewer asks: is drinking purified water basically pointless? Plenty of people say so: the filter strips out the minerals. So it does nothing for you, and even pulls calcium out of your body. That's only a small part right. Let's set two glasses side by side: purified on the left, tap on the right. What's the same, and what's different?
First, what's the same. When you drink, what your body wants most is the water itself. Your blood needs it to flow, your sweat needs it to cool you, your kidneys need it to flush out waste. Both glasses do these jobs exactly the same. An adult needs roughly 1.5 to 1.7 liters of water a day. With purified water, you get every drop of that. So where's the difference?
Tap water carries a little dissolved calcium and magnesium. That white crust in your kettle is what they leave behind. Purifying takes almost all of it out. So how much is lost? One study tested tap water in 314 Chinese cities: about 40 milligrams of calcium per liter, on average. Drink a liter and a half, and that's about 60 milligrams. Adults are advised to get 800 milligrams of calcium a day. That's less than a tenth.
How much is 60 milligrams? About a quarter of a glass of milk. The other nine-tenths was always coming from food: milk, tofu, leafy greens. But does it pull calcium out of you? No. Almost all your calcium is stored in your bones. Hormones and kidneys keep your blood level steady, and a glass of water can't wash it away.
In 2020, Germany's Federal Institute for Risk Assessment reviewed the research. Their conclusion: with a normal diet, drinking low-mineral water long-term shows no sign of harm. They also noted there still aren't many studies on it. They flagged a few groups to watch: people with very narrow diets, who skip dairy and rarely eat soy, and pregnant or breastfeeding mothers. If purified water is all they drink, they should get enough calcium from food. And after more than ninety minutes of sweaty exercise, don't rely on it alone to refill.
So no, purified water isn't pointless. It does every job water should do. The calcium it lacks is about a quarter glass of milk, easily made up at the dinner table. So, which version had you heard: that it has no nutrition, or that it drains your calcium?
Two glasses, side by side
Plenty of people say: purified water has the minerals filtered out, so it does nothing for you, and it even pulls calcium out of your body.
Only a small part of that is right: the minerals really are filtered out. The other two claims? Look at these two glasses.
The jobs water does:
both glasses, the same
When you drink, what your body wants most is the water itself. Purified water does every one of these jobs:
An adult needs roughly 1.5 to 1.7 liters of water a day. With purified water, you get every drop of that. To follow a sip of water through your body, see the hot vs. warm water episode.
How much calcium
is actually missing?
Tap water carries a little dissolved calcium and magnesium. That white crust at the bottom of your kettle is what they leave behind. Purifying takes almost all of it out.
One study tested tap water in 314 Chinese cities: about 40 milligrams of calcium per liter, on average. Drink a liter and a half a day, and that's about 60 milligrams.
Less than a tenth: about a quarter of a glass of milk.
The other nine-tenths was always coming from food: milk, tofu, leafy greens. And tap water varies a lot. In some cities it has just two or three milligrams of calcium per liter, barely more than purified water.
Does it wash calcium
out of your bones?
No. Almost all of your calcium is stored in your bones.
Hormones and your kidneys keep the calcium in your blood at a steady level. A glass of water can't wash it away.
In 2020, Germany's Federal Institute for Risk Assessment reviewed the research. Their conclusion: with a normal diet, drinking low-mineral water long-term shows no sign of harm. They also noted there still aren't many studies.
Who should
pay attention
If purified water is all they drink, these people should make sure they get enough calcium from food:
Which water to drink day to day? See the plain, mineral or electrolyte water episode.
Quick check
Drinking only purified water instead of tap water: what's the main difference?
Both glasses do every job water does; purified water just lacks tap water's bit of calcium, easily made up with food.



