In This ArticleView AllIn This ArticleWhat’s the link between dehydration and blood sugar?How to Stay Hydrated to Prevent High Blood SugarFAQs
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In This Article
What’s the link between dehydration and blood sugar?
How to Stay Hydrated to Prevent High Blood Sugar
FAQs
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When you think of all the things that can impact your blood sugar level, hydration may not be the first thing that comes to mind. But it plays an important role. “People believe that it’s just diet and weight, but there areso many other factorsthat impact blood sugar,” saysEsther Tambe, MS, RD, CDN, CDCES, owner and founder of Esther Tambe Nutrition. One of those things is hydration.
Considering that more than 10% of the U.S. population is living with diabetes and 38% of those 18 and older have prediabetes, per theCenters for Disease Control and Prevention (CDC), it’s important to consider different ways to support blood sugar regulation. We spoke with two registered dietitians who are Certified Diabetes Care and Education Specialists (CDCES) about the link between dehydration and high blood sugar.
Dehydration is a risk factor for hyperglycemia, especially among those living with diabetes. There are a couple of reasons for this: Dehydration makes your blood more concentrated, and it may alter hormones related to blood sugar control. Some research even suggests that over time, dehydration might increase your risk of developing diabetes in the first place, although more research is necessary to confirm this link.
Dehydration Increases Glucose Concentration in the Blood
Your blood sugar levels are essentially a measurement of glucose concentration in your blood, according to theNational Institutes of Health(NIH). It becomes elevated in those experiencing diabetes because insulin, the hormone that helps move glucose (sugar) from your blood to your cells, either isn’t working properly or your body doesn’t produce enough of it.
But let’s get back to the H2O part: You’ve probably heard that your body is 50%–60% water. Well, some of that water makes up your blood volume. If you’re dehydrated, your blood may become more concentrated since your body has less fluid to work with. As a result, your blood sugar levels can rise, says Tambe.
Dehydration May Impact Hormones Related to Glycemic Control
Interestingly, a 2019 study in theJournal of Applied Physiologyfound that in healthy adults without diabetes, acute dehydration didn’t alter blood sugar regulation as measured via an oral glucose tolerance test. It did cause copeptin levels—an indirect measure of vasopressin—to rise, though.
Those with Diabetes May Have Higher Fluid Needs
Frequent urination can be a symptom of hyperglycemia, per theNIH, which may lead to a vicious cycle of further dehydration in those with diabetes. A 2018 study in theAnnals of Nutrition and Metabolismthat assessed hydration during physical activity among people with type 1 diabetes found that participants still felt thirsty after drinking sufficient water according to sport nutrition guidelines. This makes sense, since increased thirst is another sign of hyperglycemia. The authors noted that while it’s unclear why those with type 1 diabetes have higher fluid needs than those without the condition, one explanation is that excess urination could lead to greater fluid loss.
How Dehydration May Increase Diabetes Risk
While there isn’t much research on this subject, the same study referenced above inDiabetes Carefound a link between lower water intake—particularly among those drinking less than 0.5 liters per day—and greater new-onset hyperglycemia (high blood sugar). The study was observational, meaning it couldn’t establish that the dehydrationcausedthe hyperglycemia, but it did show a significant link between the two.
People Without Diabetes May Not Notice Hyperglycemia
Tambe andDiana Mesa RD, LDN, CDCES, founder and owner of En La Mesa Nutrition, say that dehydration can temporarily raise blood sugar inthose without diabetes, too. Plus, theCDCestimates that 23% of those living with diabetes are undiagnosed. People who have been diagnosed with diabetes are typically accustomed to checking their blood sugar and noticing signs of hyper- or hypoglycemia. For those without a diabetes diagnosis, this may not be top of mind.
Also, dehydration and hyperglycemia largely overlap, so it may be tough to determine what’s causing your symptoms. Commonsymptoms of dehydrationinclude thirst, fatigue, dizziness, dry mouth, less frequent urination, dark-colored urine and dry skin. Symptoms of hyperglycemia include feeling thirsty, tired or weak, headaches, urinating often and blurred vision, per theNIH. Notice that most of the symptoms overlap; the biggest difference is that dehydration reduces urine frequency, while hyperglycemia increases it.
Staying hydrated is important for blood sugar regulation, but you may struggle to get enough fluids in. If you have a job that hinders you from hydrating during the day or you don’t like plain water, you may need to get creative! Here are some ideas for staying hydrated to promote blood sugar control:
The Bottom Line
Frequently Asked QuestionsWhen you’re dehydrated, your blood sugar typically goes up because your blood will be more concentrated. Therefore, the concentration of sugar relative to the volume of your blood will be higher.Since dehydration can cause high blood sugar, drinking water can certainly help lower blood sugar if you’re dehydrated. If you have diabetes, there are other factors that lead to high blood sugar, so you’ll also need to consider your food choices, exercise habits, and doctor-recommended medications to help manage your blood sugar.Dehydration and high blood sugar have many symptoms in common, including thirst, feelings of tiredness or weakness, headaches and blurred vision, per theNIH. Mesa says that they can also both impact your mood and cognitive function, which can further hinder you from practicing health-promoting behaviors. However, high blood sugar levels can also lead to frequent urination, whereas dehydration does the opposite.
Frequently Asked Questions
When you’re dehydrated, your blood sugar typically goes up because your blood will be more concentrated. Therefore, the concentration of sugar relative to the volume of your blood will be higher.
Since dehydration can cause high blood sugar, drinking water can certainly help lower blood sugar if you’re dehydrated. If you have diabetes, there are other factors that lead to high blood sugar, so you’ll also need to consider your food choices, exercise habits, and doctor-recommended medications to help manage your blood sugar.
Dehydration and high blood sugar have many symptoms in common, including thirst, feelings of tiredness or weakness, headaches and blurred vision, per theNIH. Mesa says that they can also both impact your mood and cognitive function, which can further hinder you from practicing health-promoting behaviors. However, high blood sugar levels can also lead to frequent urination, whereas dehydration does the opposite.
Originally appeared: EatingWell.com, September 2023
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