Staying hydrated is important for everyone — especially considering that water makes up more than half of the human body!

“60 percent of our body is composed of water, 75 percent in our muscles, 85 percent in our brains, it’s like oil to a machine,” explained Dr. Roberta Lee at Medicine Daily.

As people with diabetes, drinking enough water is especially crucial. Even a little dehydration during the day (which is easier than we realize) can impact our blood sugars.

This article will explain how dehydration affects blood sugar levels, how much water we should drink each day, who should limit their water intake, and what else you can drink if you don’t want to just drink plain water.

Water & Diabetes - Are you drinking enough water

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How water impacts your diabetes

Quite simply, when you don’t drink enough water, the glucose in your bloodstream becomes more concentrated. And that leads to higher blood sugar levels. Both mild and severe dehydration can have a notable impact on your diabetes.

Even a mild level of dehydration — something you may not even feel — could easily leave your blood sugar levels 50 to 100 mg/dL higher than if you were drinking enough water.

If you’re consistently dehydrated on a daily basis, you might even be compensating with higher insulin levels than you’d need if your body was getting the water it needed.

More severe levels of dehydration, on the other hand, can drive blood sugars very high very quickly. For example, repeated vomiting from food poisoning or a stomach virus can lead to very sudden high blood sugar levels. But after an IV of fluids at the emergency room, you’ll likely see your blood sugar drop quickly towards normal levels without additional insulin.

It’s the simple issue of severe dehydration causing the glucose in your bloodstream to become extremely concentrated, and then quickly diluting it with plenty of fluids.

Almost every process in your body relies on water

Water actually does far more for our bodies than we realize. Water aids your digestion, lubricates joints, helps flush waste products, and performs a host of other important tasks in your body. Not being properly hydrated will significantly reduce your physical capacity and brain function. 

According to Harvard University, adequate water intake is vital for a variety of daily functions within our body:

  • carries nutrients and oxygen to cells throughout your body
  • flushes bacteria from your bladder
  • aids in the digestion of meals
  • prevents constipation
  • normalizes your blood pressure
  • maintains a stable heartbeat
  • cushions your joints
  • protects your organs and tissues from a variety of potential damage
  • regulates your body temperature
  • maintains your body’s electrolyte/sodium levels

Water has been pinpointed in many studies as an important part of losing weight, but researchers still aren’t clear how it’s accelerating your weight-loss efforts.

Theories behind water consumption and weight loss include:

  • Drinking more water means you’re likely drinking less soda and other sugar-laden beverages
  • Drinking more water might boost your metabolism and cause you to burn more calories
  • Drinking more water might help reduce cravings for not-so-healthy foods
  • Drinking more water in place of diet soda may reduce insulin resistance

Regardless, it is clear in study after study that those who drink more water tend to lose more weight, in contrast, to study participants drinking less water.

Drinking enough water impacts so many aspects of our daily health. But how much water is enough?

How much water should people with diabetes drink each day?

There is no definitive rule for how much water you should drink, but there are guidelines we can follow.

The most important recommendation is that you should always have water available and drink whenever you feel thirsty. You don’t need to force yourself to drink water to reach some specific goal, but try to drink water continuously throughout the day.

Even if you don’t feel thirsty, you should try to take a few sips of water every hour to keep hydrated. The thirst reflex isn’t always perfect, especially for people with diabetes, so it’s better to proactively drink a little water than risk dehydration.

The average non-diabetic is advised to drink 8 glasses of water per day, so a person with diabetes should certainly take that to heart. While our insulin-producing friends need plenty of water, too, the consequences of mild dehydration in those of us with diabetes are more obvious in our blood sugar levels.

8 glasses of water per day add up to about 2 liters of water (67 ounces or just over half a gallon). It sounds like a lot — but you can make it feel more doable by choosing a medium-sized reusable beverage container and determining how many times per day you need to fill it to reach 2 liters.

If you’re exercising or battling the heat of summer, that number increases quickly.

“But even a healthy person’s water needs will vary,” adds Harvard, “especially if you’re losing water through sweat because you’re exercising, or because you’re outside on a hot day.”

Harvard research says the general rule of thumb for healthy individuals on a hot day or during exercise is to drink two to three cups per hour to compensate for water lost through sweating.

Who should limit their water intake?

“It’s possible to take in too much water,” explains Harvard research.

Certain health conditions can mean that too much water is actually taxing on your body. These conditions and medications mean you should talk to your doctor about the right amount of daily water for your body:

Good alternatives to plain water

Most sugar-free non-calorie beverages are good alternatives to plain water. This includes:

  • Flavored or infused water
  • Sparkling water
  • Unsweetened tea
  • Diet soda (in limited amounts)

Coffee in small amounts is also hydrating, as the diuretic effect of coffee (making you urinate more) is less than the amount of liquid you drink. 

A note on diet soda

Some research studies point to a link between insulin resistance, weight gain, and frequent consumption of diet soda.

As one study from the United Kingdom concluded, “Replacement of [diet beverages] with water after the main meal in women who were regular users of [diet beverages] may cause further weight reduction during a 12-month weight maintenance program. It may also offer benefits in carbohydrate metabolism including improvement of insulin resistance over the long-term weight maintenance period.”

However, other studies have not found the same effects of diet soda so it’s probably safe to consume diet soda in limited amounts.