Does Dehydration Raise Blood Sugar in Non-Diabetics? Here's What a Dietitian Says

Yes, dehydration can temporarily raise blood sugar levels in non-diabetics. This occurs because water makes up a significant portion of your blood volume. When you become dehydrated, the water content in your blood decreases, causing the concentration of glucose (blood sugar) to rise.

Given that over 10% of the United States populace grapples with diabetes and 38% of those aged 18 and above are on the brink of prediabetes, as per the Centers for Disease Control and Prevention (CDC), it becomes imperative to explore diverse approaches in maintaining blood sugar equilibrium.

Does Dehydration Raise Blood Sugar in Non-Diabetics?
Does Dehydration Raise Blood Sugar in Non-Diabetics?

We engaged in discussions with two certified dietitians who also hold the designation of Certified Diabetes Care and Education Specialists (CDCES) to delve into the correlation between dehydration and elevated blood sugar levels.

The link between dehydration and blood sugar is a complex one, but the basic understanding is this: dehydration can cause a temporary increase in blood sugar levels in both diabetics and non-diabetics.

Here’s how it works:

  • Water makes up a significant portion of your blood volume.
  • When dehydrated, the water content in your blood decreases.
  • This concentrated blood volume leads to a higher concentration of glucose (blood sugar).
  • This results in a temporary spike in blood sugar levels.

However, the extent to which dehydration affects blood sugar varies depending on several factors:

  • Severity of dehydration: Mild dehydration is unlikely to cause significant blood sugar changes.
  • Individual health status: People with existing health conditions, like diabetes, are more susceptible to blood sugar fluctuations from dehydration.
  • Activity level: Exercise and sweating can exacerbate dehydration and magnify its impact on blood sugar.
  • Diet: High sugar intake can worsen blood sugar spikes due to dehydration.

Here’s a deeper look at the link for both diabetics and non-diabetics:

For Diabetics:

  • Dehydration can significantly impact diabetics, as their bodies have difficulty regulating blood sugar levels.
  • High blood sugar can lead to dehydration, creating a vicious cycle.
  • Dehydration can also decrease the effectiveness of insulin, further impacting blood sugar control.

For Non-Diabetics:

  • While not as severe as in diabetics, dehydration can still cause temporary blood sugar spikes in healthy individuals.
  • This is especially true during periods of increased sweating, like exercise or hot weather.
  • Chronic dehydration can increase the risk of developing diabetes over time.

Remember, staying hydrated is crucial for overall health, including blood sugar control. By taking steps to prevent dehydration, you can maintain optimal health and well-being.

How to Stay Hydrated to Prevent High Blood Sugar

Staying hydrated is crucial for overall health, and it plays a significant role in managing blood sugar levels. When you’re dehydrated, your blood volume decreases, leading to a higher concentration of glucose (sugar) in your blood. This can cause temporary spikes in blood sugar, even in non-diabetics.

Does Dehydration Raise Blood Sugar in Non-Diabetics?
Does Dehydration Raise Blood Sugar in Non-Diabetics?

Here are some tips on how to stay hydrated and prevent high blood sugar:

1. Drink Plenty of Water:

Water is the best choice for hydration. Aim for at least eight 8-ounce glasses of water per day, but adjust based on your individual needs and activity level. You may need to drink more water in hot weather, during exercise, or if you have a fever.

2. Choose Water-Rich Foods:

Fruits and vegetables are naturally high in water content. Include a variety of these foods in your diet to help you stay hydrated. Some good options include watermelon, cucumber, strawberries, and spinach.

3. Monitor Your Urine Color:

Your urine color is a good indicator of your hydration level. Pale yellow or clear urine indicates you’re well-hydrated. Dark yellow or amber-colored urine indicates dehydration.

4. Limit Sugary Drinks and Alcohol:

Sugary drinks and alcohol can contribute to dehydration. It’s best to limit these beverages and opt for water or unsweetened tea instead.

5. Consider Other Beverages:

While water is the best choice for hydration, other beverages can also help you meet your fluid needs. These include unsweetened tea, coffee, and seltzer water.

6. Eat Regularly:

Eating regular meals can help you stay hydrated. When you eat, your body absorbs the water content from the food. Aim for three balanced meals and two healthy snacks per day.

7. Listen to Your Body:

Pay attention to how your body feels. If you’re thirsty or feel tired and sluggish, you may be dehydrated. Drink plenty of water and rest until you feel better.

8. Carry a Water Bottle:

Carrying a water bottle with you is a great way to ensure you have access to water throughout the day. Take sips regularly, even if you don’t feel thirsty.

9. Use Hydration Apps:

There are many hydration apps available that can help you track your fluid intake. These apps can be helpful reminders to drink water and stay on track with your hydration goals.

10. Consult Your Doctor:

If you’re concerned about your blood sugar levels or have any questions about hydration, talk to your doctor. They can provide you with personalized advice and recommendations.

By following these tips, you can stay hydrated and help prevent high blood sugar levels. Remember, staying hydrated is important for your overall health and well-being.

Frequently Asked Questions about Dehydration and Blood Sugar

Q: Does dehydration always raise blood sugar?

A: Not always. The severity of dehydration and individual health factors play a role. While mild dehydration may not significantly impact blood sugar in non-diabetics, severe dehydration can cause temporary spikes for both diabetics and non-diabetics.

Q: How much water should I drink to prevent blood sugar spikes?

A: Aim for at least eight 8-ounce glasses of water per day. However, individual needs vary based on factors like activity level, climate, and health conditions. Consult your doctor for personalized advice.

Q: Can other beverages besides water help me stay hydrated?

A: Yes, unsweetened tea, coffee, and seltzer water can contribute to your fluid intake. However, sugary drinks and alcohol dehydrate you, so limit those.

Q: What are some symptoms of dehydration?

A: Common symptoms include thirst, fatigue, headache, dizziness, dark-colored urine, and dry mouth.

Q: What if I find it difficult to drink plain water?

A: Try adding slices of citrus fruits, cucumber, or berries to your water for flavor. You can also infuse water with herbs like mint or basil. Eating water-rich fruits and vegetables can also help you stay hydrated.

Q: I exercise regularly. Should I drink more water than usual?

A: Yes, exercise increases sweating and fluid loss. Increase your water intake before, during, and after exercise to stay hydrated.

Q: Should I be concerned if my urine is dark yellow?

A: Dark-colored urine is a sign of dehydration. Aim to drink more fluids until your urine becomes pale yellow or clear.

Q: I have diabetes. How does dehydration affect my blood sugar control?

A: Dehydration can significantly impact blood sugar in diabetics, making it important to stay consistently hydrated. Consult your doctor for personalized guidance on managing your blood sugar and fluid intake.

Q: Where can I find more information about dehydration and blood sugar?

A: You can find reliable information on websites of reputable organizations like the National Institutes of Health (NIH), the American Diabetes Association (ADA), and the Mayo Clinic.

Bottom Line

Inadequate water intake throughout the day may impede glycemic control, especially for individuals managing diabetes. Dehydration and hyperglycemia exhibit several shared symptoms, making it easy to misconstrue one for the other. To distinguish between them, observe your urine frequency—hyperglycemia often leads to frequent urination, while dehydration diminishes it. Ensure you have a water bottle within reach and explore imaginative ways to make fluid consumption enjoyable, thereby supporting your overall well-being, including the regulation of blood sugar levels.

Sources for information in this conversation:

Dehydration and Blood Sugar:

Staying Hydrated:

Additional resources:


This list is not exhaustive and should not be considered a substitute for professional medical advice. Please consult your doctor or a registered dietitian for personalized information and guidance regarding dehydration and blood sugar management.