So much of the health advice we hear has to do with staying hydrated. But it can be hard to stay motivated ounce after ounce, or to even know which advice is real or not. Don't worry, we've got you covered.

We are water

Water molecules account for 70% or more of a total cell mass, making it the most abundant molecule in our bodies. The percentage of water in the body peaks around 75% in infants and goes as low as 45% in older populations.

One big reason for this is simply that oil and water don’t mix. Meaning fat tissues will naturally contain less water than other tissues (like muscles). And because we also tend to lose lean muscle mass as we age, it makes sense that we would also lose the supplies of water those tissues contain.

Electrolyte is just a fancy word for salt

The term “electrolytes” gets thrown around a lot when we’re talking about hydration and guess what—it’s basically a fancy scientific word for salts.

When we say salts, we’re talking about things like potassium, magnesium, sodium, and chloride. And yes, that’s the same sodium and chloride that make up table salt.

Sometimes your cells get salty

Salt has a bad reputation and for good reason. The amount of salt in our blood (sodium specifically), is very closely tied to blood pressure. Which is why people suffering from hypertension are often advised to eat low-sodium diets. But the levels of salt in our blood also serve a necessary purpose.

Salts help our cells and tissues stay the right size through a process called “osmosis,” which you may remember from high school biology. Water tends to enter cells with more “stuff” in them (salts, proteins, other molecules) compared to their surroundings. That balance between salt and water controls the size of our cells. Meaning they can actually swell if they gain too much water or shrink if they lose too much.

Kidneys do the heavy lifting

At any given time, 20–25% of your blood is going through your kidneys. Our kidneys are what maintain our internal balance between water and salts (electrolytes). This proper balance is essential for pretty much all of our bodily functions. Thankfully, we have a lot of systems in place to ensure this balance stays where it needs to be.

Staying hydrated requires a lot of energy (and NAD)

Your kidneys work very hard to actively control what stays in your blood or leaves your body. This process requires a ton of cellular energy. Your cells wouldn’t be able to generate any of that energy without NAD (nicotinamide adenine dinucleotide).

Caffeinated beverages don’t actually dehydrate you

One of the many myths floating around about caffeine is that it dehydrates you. This assumption is based off the fact that caffeine is a diuretic, meaning it enhances urinary output and can help eliminate excess water and salts from the body. Although caffeine is a diuretic, if you’re drinking it in a beverage it offsets the water loss.

If you’re thirsty, you’re already dehydrated

There’s a reason why this phrase is so well-known. Losing only 1–2% of your body’s total water can cause a mild but marked decline in cognitive performance. This is also the same time your body starts to trigger the sensation of thirst. Meaning that by the time you feel thirsty, you’re already mildly dehydrated.

Coconut water might be better for you than plain water

One study tested sodium-enriched fresh young coconut water, fresh young coconut water that wasn’t enriched with sodium, a sports drink, and plain water to see which did best at rehydrating. The answer? Sports drink and sodium-enriched coconut water rehydrated better than plain water.

Drinking water can’t really prevent headaches

You may have noticed a headache when you get dehydrated, but there is surprisingly very little research that can explain this phenomenon. One study done by a group of curious medical students showed evidence that dehydration headaches are real.

The 8 x 8 rule may not work for you

Most health professionals recommend drinking eight glasses of eight ounces of water every day. But the reality is (as usual) more complex than that. How much water we need to stay hydrated depends on a host of factors like our body type, environment, and level of physical activity. The 8 x 8 rule is just a guideline.

Salt cravings are real

Dehydration can also lead to a sodium imbalance, which can create a sensation known as “salt appetite.” Your body literally craves salt because you need more of it.

Eat food when you’re bored with drinking water

This may seem obvious but just like humans are almost 50–60% water, our foods also contain a high percentage of this life-giving molecule. So, eating foods with a higher water content can help keep us hydrated.

We also create water when metabolizing fats and sugars (another process that requires NAD). Some animals hardly ever drink because they make all the water they need from food. We’re not saying that works all the time, but if you’re bored with drinking water, there are some other tastier options.