Why Healthy Blood Sugar Levels Matter, Even if You Don’t Have Diabetes

Julia Malacoff
Medically Reviewed
March 2, 2021

Most people don’t associate symptoms like waking up in the middle of the night and irregular menstrual cycles with blood sugar problems. Actually, most people aren’t thinking about maintaining healthy blood sugar levels at all.

“The details of blood sugar regulation are sometimes an issue that isn’t examined closely until you’re dealing with a serious clinical diagnosis like diabetes or prediabetes. But these aren’t conditions that occur overnight,” explains Jaclyn Tolentino, DO , a board-certified family medicine physician with Parsley Health. “There’s a lot of opportunities to explore blood sugar issues and adopt healthy strategies for blood sugar regulation before they become a serious clinical issue.”

This is one of the reasons Parsley patients are carefully screened for prediabetes and diabetes, but also other issues like low blood sugar, insulin resistance (a precursor to prediabetes), and fluctuations in blood sugar that might not qualify for a diabetes diagnosis but are problematic nonetheless. This way, Parsley clinicians are able to catch smaller blood sugar problems before they snowball into something bigger, and generally help people learn more about the ways their bodies react to certain foods .

And often, blood sugar problems can be intertwined with other health issues such as SIBO , PCOS , and more. That’s part of why managing blood sugar should be considered a foundational health practice, right up there with managing sleep and stress, according to Erica Favela , a health coach at Parsley Health. In other words, managing your blood sugar isn’t just for people with blood sugar problems.

What happens when blood sugar is out of whack?

Blood sugar is a measure of the amount of glucose in our blood. When we eat carbohydrates, glucose enters the bloodstream and is regulated by the hormones insulin and glucagon. Ideally, the amount of glucose rises a bit (but not too much) when we eat, then returns to normal. “What we’re trying to avoid is wild swings where our blood sugar rises too high (or stays high), or dips too low before normalizing,” Dr. Tolentino says.

There are a few different ways things can go wrong:

Hyperglycemia, or high blood sugar,happens when there’s too much sugar in the bloodstream. “Generally this looks like a blood glucose level of more than 180 mg/dL one to two hours after eating,” Dr. Tolentino says. High blood sugar symptoms include:

  • increased thirst
  • blurred vision
  • frequent urination
  • headache

Hypoglycemia, or low blood sugar, is when there’s too little sugar in the blood. “Symptoms might occur around blood glucose levels of 70 mg/dL or lower,” Dr. Tolentino notes. Low blood sugar symptoms include:

  • pale skin
  • sweating
  • dizziness
  • hunger
  • headaches
  • shaking
  • irritability
  • anxiety

Insulin resistance is a specific condition that develops in response to a flood of sugar into the bloodstream. Basically, cells stop responding to insulin the way they should, and blood sugar continues to rise over time. Insulin resistance doesn’t always produce noticeable symptoms , but it increases your risk of diabetes and metabolic syndrome. In the early stages, insulin resistance doesn’t necessarily cause blood sugar fluctuations that feel extreme. But over time, people with insulin resistance may experience the symptoms of high or low blood sugar.

“In prediabetes and diabetes, we often see blood sugar levels that remain substantially elevated for an extended period of time after meals,” Dr. Tolentino says. ”We may also see dips in blood sugar, especially related to improperly balanced meals or vigorous physical activity.” Insulin resistance is also a common feature of diabetes and prediabetes.

But all three of these issues can also happen in peoplewho don’t meet the diagnostic criteria for diabetes or prediabetes. And that’s a problem. “In general, we shouldn’t be experiencing big spikes and dips in energy in response to the things we eat ,” Dr. Tolentino says.

Symptoms of blood sugar problems (that may be surprising)

Outside of experiencing the signs of hyperglycemia and hypoglycemia, there are some other red flags Parsley practitioners look out for that could indicate it’s a good idea to take a deeper look into blood sugar and insulin levels. These include:

  • disrupted sleep cycles
  • irregular menstrual periods
  • hormonal imbalance (in both women and men)
  • abnormal/unexpected weight gain or loss
  • digestive issues
  • general fatigue
  • sudden energy crashes (especially in the afternoon)
  • feeling extremely hungry in between meals
  • food cravings (especially for sugar)
  • mood problems

Testing and monitoring blood sugar

Because symptoms can be vague, uncovering blood sugar problems often requires taking a deeper look. “One of the first steps we take is getting a full and complete picture of a patient’s nutritional status, which is an instance where I really like to use an in-depth food journal ,” Dr. Tolentino says. “That way, we’re getting the full picture, including details of how you’re feeling after every meal.”

Those extra details about your eating habits—beyond just what you eat—are really important, Dr. Tolentino emphasizes. “People who have a great diet may not be looking at blood sugar issues as a cause of problems like frequent fatigue or afternoon energy crashes, even if blood sugar ultimately is one of the culprits. When we eat and how much we eat can often be just as significant as what we’re eating .”

When trying to assess someone’s risk of blood sugar problems, some of the questions Favela asks are:

  • How are you feeling in between your meals?
  • Do you feel like you have to have a snack in between your meals?
  • Can you go solid four to five hours between meals?
  • Do you ever feel “hangry” (anxious, agitated, unable to concentrate) between meals?

“With normal hunger, you can tap into body sensations,” Favela explains. For instance, your stomach might be growling. But people experiencing blood sugar fluctuations often feel the need to eat urgently, eat frequently, and can’t go more than three to four hours between meals.

Aside from asking careful questions, blood sugar testing can also be used to uncover fluctuations. “We do a comprehensive lab assessment to test fasting blood sugar and insulin levels, hemoglobin A1c, markers of organ function, as well as looking at things like inflammatory, micronutrient, and hormone markers,” Dr. Tolentino says. Other testing could include an oral glucose tolerance test (if you or someone you know has been pregnant, this is the test they do that involves drinking a sugary solution) and urinalysis.

When appropriate, Dr. Tolentino also uses a continuous glucose monitor , which is a wearable device that takes a measurement of blood sugar about every five minutes. “This means you’re effectively getting real-time data on fluctuations in your blood sugar, and you’re getting a much clearer picture, especially after meals or when you first wake up.”

Tips for maintaining healthy blood sugar levels

If a problem is uncovered, it’s important to create a multi-faceted game plan for healthy blood sugar levels. “We’ve got to look at sleep, stress, exercise, and movement, as well as nutrition to develop an effective long-term strategy,” Dr. Tolentino says.

The good news is that whether you want to lower blood sugar, raise blood sugar, increase insulin sensitivity, or just generally manage your blood sugar, many of the recommendations are the same, Favela says. “If you focus on a few of the principal pieces, a lot of these things kind of resolve themselves.”

Balance carbohydrates with protein and fat.

Carbohydrates have the biggest impact on blood sugar. “But protein and fat are going to slow down the rate at which those carbohydrates are broken down, and give you more blood sugar stability,” Favela says. So rather than restricting carbs right off the bat, she likes to encourage people to focus on creating meals and snacks that include carbs, protein, and fat.

Often just this small change can make a big difference in helping to achieve healthy blood sugar levels, according to Favela. “If we switch up someone’s breakfast to something that’s more balanced, all of a sudden a light bulb goes off and they’re like, ‘Oh, this is what it feels like to feel stable and to feel calm and to feel clear-headed.’”

Focus on quantity and quality of carbs.

For people who are showing signs of insulin resistance or other blood sugar problems, Favela also recommends paying attention to the quality and quantity of carbohydrates. “We always want to go towards whole foods because those will give us more fiber , which helps to slow down that blood sugar release,” she says. That could look like choosing sweet potatoes over gluten -free bread, for example. Choosing carbohydrates based on the glycemic load, or a measure of how much impact they’ll have on blood sugar, can also be helpful.

In terms of quantity, portion size recommendations need to be individualized, Favela says, but changing up portion sizes is something to consider if even high-quality carbohydrates are causing blood sugar fluctuations. Favela works with her members at Parsley to determine the right foods and portions for them based on how their bodies respond.

Tap into how eating makes you feel.

“A part of blood sugar regulation is really about thinking more intuitively about meals and eating: how we feel after we eat, how eating certain things specifically makes us feel, whether we’re taking the time to eat slowly or we’re just rushing through our meals at our desks or standing up at the kitchen counter,” Dr. Tolentino explains. “All of these things provide us with really valuable data on how the process of eating impacts our bodies.”

Dr. Tolentino says that by gathering this information from her patients, she’s able to help them shift their eating patterns to better balance blood sugar.

Know that everyone is different.

“What works for an individual and their blood sugar balance is very unique,” Favela points out. Some people tolerate certain types of carbohydrates really well, and others don’t. “For one person, a bowl of oatmeal might keep them stable for four hours. For another person, it might totally drop them two hours later. So it takes a little bit of self-experimentation, and really asking yourself those questions about how you feel from one meal to the next to figure out what works for you.”

Keep up with exercise.

“Some people think that the only way that they can change their blood sugar is through diet,” Favela says. But you can actually improve insulin sensitivity blood sugar regulation through exercise. “Both high-intensity exercise and moderate aerobic exercise can be really helpful for supporting better blood sugar responses,” Favela adds.

Practice healthy sleep habits.

“With sleep, it’s kind of like a chicken or the egg thing,” Favela notes. Blood sugar dysregulation can cause sleep disturbances, and poor sleep can cause blood sugar dysregulation and insulin resistance. “So we want to make sure that you’re practicing good sleep hygiene and sleeping well because that’s also going to help your blood sugar the next day.” Plus, getting good sleep will help make some of the other practices on this list easier, like making smart food choices and fitting in exercise.

Manage stress.

Most people don’t realize that stress alone can impact blood sugar. Sometimes, patients can see this in action when they wear a continuous glucose monitor. “You can eat nothing, but then have a highly stressful scenario, and that will raise your blood sugar due to stress hormones that come out into the blood,” Favela explains. When you’re in “fight-or-flight” mode, the body thinks it needs energy and releases glucose into the bloodstream.

Stress can also play into habit loops: You’re stressed, and you want a quick reward. “And what is that reward going to be? It’s going to be sugar, and then that leads to blood sugar destabilization,” Favela says. “This creates a pattern and spiral that we have to break .”

The takeaway:

Your blood sugar levels can have a big impact on how you feel day-to-day, so learning to balance them through your diet, exercise, and lifestyle habits can help you feel your best and avoid future health issues. Not everyone’s blood sugar levels will react the same to changes though, so working with a holistic medicine practitioner can be valuable for determining what’s best for your body.

Julia Malacoff

Julia Malacoff is an Amsterdam-based freelance writer, editor, and certified personal trainer. She covers a wide range of wellness topics including nutrition, fitness, specific health conditions, and the latest scientific research in these field. Julia graduated from Wellesley College and she works with brands like Shape, Cosmopolitan, Fast Company, Precision Nutrition, Equinox, and Aveeno. Outside of work, you can find her walking her dog, trying out a new recipe, or learning Dutch.

Read full bio
readiness quiz

Get a snapshot of your health - right now.

Take our quiz to get your symptom score and start uncovering the why behind your symptoms.

Related Posts
Get “Prescription for Happiness” and Reach a New Level of Energy, Clarity, and Calm
How to Select the Right Health Coach for You
10 TikTok Health Trends Worth Trying—and Avoiding
12 Gifts For The Well-Being Seekers In Your Life
Four Smart Ways to Track Your Heart Health Today
Doctor examining patient


Our leading medical providers and health coaches heal the root cause of health concerns with a personalized care plan and year-round support. Our root-cause resolution medicine has helped thousands feel better, with 85% of members reducing symptoms in their first year.

Parsley Health medical providers are trained to treat the root cause of complex, chronic conditions and symptoms. Ready to start feeling better?

Get Symptom Score