Improve your health by learning

Diabetes Basics

Diabetes Monitoring

Diabetes & Nutrition

Diabetes & Exercise

< Go back

Lifestyle Habits that Affect Your Blood Sugars

Nina Ghamrawi, MS, RD, CDE
November 12, 2021

Before you developed glucose intolerance, no matter what you ate or how active you were, your blood glucose (sugar) levels stayed within a normal range. But now, you may be realizing that many factors and habits can change your blood glucose levels. Learning about these factors can help you control them.

1. Meal Timing

Timing of your meals is extremely important. If meals are too close together, ie. less than 4 hours apart, you run the risk of making glucose higher before your body can completely use what you consumed from the last meal. Meals too far apart may cause your blood sugars to dip or leave you lacking energy.

Skipping meals will have a similar effect, going longer than 6 hours between meals, or doing strenuous activity while delaying a meal, may cause your liver to take action. When glucose is at risk of being low, we often don’t feel it. The body will sense impending low glucose, and kick your liver into action to produce sugar from storage. This may actually have the reverse effect on your glucose - instead of getting low blood sugars from skipping a meal, they may spike instead.

2. Sleep Routine

Not getting adequate sleep, or enough sleep, is not a factor that all of us have within our control. But knowing how your body responds to sleep is very important to making sense of our numbers. Every night—regardless of whether you sleep—your blood sugar levels increase as a part of the natural human circadian rhythm cycle. When we don’t get enough sleep, the following things may happen:

  • Sleep deprivation: causes oxidative stress and Inflammation and insulin sensitivity
  • Irregular routine: the time of day a person sleeps at night, when either too late or not consistent, causes the hormone, Cortisol, and levels of C-reactive protein to rise

All of these will either make glucose harder to control, or directly make your glucose rise. More research is needed to better understand the connection between sleep and blood sugar, but so far, the following factors have been noted to change our threshold for sleep that our body requires:

3. Food Quality and Meal Balance


Oftentimes we can’t get the most nutritious, high fiber, whole grain carbohydrates in every meal, or we may be at a special party or event and eat a little more sugar or sweet beverages than our body can handle with a glucose sensitivity. It is important to check glucose around these special occasions to know exactly how your body responds when your carbohydrates are very starchy, or you have some extra starchy or sugary meal extras.

When a meal has too little carbohydrate, this can make you lose energy or even cause low glucose. Make sure your meals are balanced.


When a meal is very high in fat, especially saturated fat like coconut, or animal fats, this may slow down how quickly your sugar gets into, and out of, your blood. When a meal is well-balanced, glucose will typically peak around 2 hours after you eat. But when your diet is high fat, it may not peak until 4-5 hours later, and glucose may not fall back to normal until 6 hours after your first bite.

If you are not sure how much carbs to eat, or you don’t know which carbohydrates your body responds better or worse to, go ahead and check! Check before your first bite, and also 2 hours after you that first bite. You’ll see a difference immediately. If your meal is a high-fat one, check 2, 4, and also 6 hours later just to see how your body handled that meal. Once you know, managing glucose gets a lot easier.

4. Sneaking in Snacks

Grabbing some munchies is not a bad idea if you’re hungry. But if you are not truly hungry, like when we stress-eat, or eat from boredom or to fill time, then we may be raising our glucose without even realizing it.

Try this trick to give your snacks some rules: have a fruit between meals during the daytime (not with meals), and pair it with some protein and fat, like low-fat dairy, nuts or nut butters. And at night, if you are hungry, snack on a high fiber whole grain, with a little protein, and/or a little calcium-rich dairy - a wheat toast with avocado and cheese would do the trick.

If you are truly hungry, then think about the reason why: sometimes we have skipped a meal, and actually need something balanced, like a mini-meal, but sometimes we may feel hungry because our last meal was missing some crucial macronutrient like fat, carbohydrate, or protein, or you may just be missing fluid or fiber. Before grabbing a snack, ask yourself: did I eat enough protein, carbohydrates, fiber, healthy fats? Did I drink enough water? Snack first, on what your body may be missing.

5. Exercise Routine (or the lack of)

Less exercise than usual can cause blood sugars to be higher than your typical. When there is less glucose demands from your muscles, then that glucose will stay in your bloodstream longer, making glucose appear higher.

More physical activity or exercise than usual can cause low blood sugars. Physical activity makes your body more sensitive to insulin and can lower blood glucose. If your body is not prone to low glucose, this may cause a similar effect as going long periods between meals.

Most importantly, when you are exercising at irregular times, either late at night (see: fueling for an evening workout), then your body may have some trouble regulating glucose demands.

6. Stressors: Pain, Stress, or Illness

Stress, be it physical or emotional can all increase stress-related hormones, and cause a significant rise in glucose. Control pain within your ability, control emotional stressors and practice healthful stress-relieving techniques when possible.