If you’re feeling tired, foggy or sleepy a few hours after eating (looking at you, 3 p.m. at the office), or if you’re noticing that your appetite picks back up sooner (or you’re eating more, or both) a few hours after eating, chances are good your blood sugar crashed after spiking post-lunch, post-dinner and so on.
What a Spike Actually Is
After a meal, blood sugar spikes (clinicians might refer to this as a postprandial rise, postprandial being a fancy way of saying after a meal) and then falls back down. If you don’t have diabetes, it’s normal for blood sugar to rise after you eat and peak around an hour after you start a meal, typically at just under 140 mg/dL, and then return to baseline within two to three hours. In one study of 153 healthy people wearing continuous glucose monitors (CGMs), participants’ average blood sugar was 99 mg/dL, and nearly all of their time was spent within the 70 to 140 mg/dL range.
The postprandial rise isn’t your body malfunctioning. It’s just evidence that digestion is occurring.
That said, postprandial blood sugar spikes vary from person to person, so what might cause a significant spike for you may only cause a small bump for someone else. It’s also worth noting that the blood sugar numbers used to diagnose prediabetes and diabetes (measured two hours after drinking a sugary beverage during an OGTT, aka oral glucose tolerance test, in a clinical setting) are 140 to 199 mg/dL and 200 mg/dL or higher, respectively. These aren’t numbers you’re likely to see after an ordinary meal, and it’s the chronicity of an impaired postprandial response that’s most concerning.
Craving dessert a couple hours after lunch? Here are five science-backed (albeit from short, small studies) ways to avoid blood sugar spikes that don’t involve CGMs, prescriptions or shelling out cash.
Habit 1: Vegetables and Protein Before the Carbohydrate
The order you eat your food in can have an effect on your blood sugar. A 2015 study that followed 11 people with type 2 diabetes found that eating the protein and vegetable components of a meal before the carb component resulted in blood sugar that was on average 29% lower 30 minutes after eating began and 37% lower one hour after eating began. Overall sugar exposure (an estimate of total blood sugar over two hours) was on average 73% lower when the carbs were eaten last.
In another study from 2017, the same researchers followed 16 people with type 2 diabetes and found that blood sugar spikes were on average 54% lower when participants ate the carbohydrate portion of a meal last compared to first.
It’s thought that eating protein and fiber first slows the rate at which food leaves your stomach so that carbs make their way into your intestines more gradually rather than all at once. In a 2024 randomized crossover trial that followed 18 healthy adults, researchers found that two-hour glucose exposure was on average 41% lower when participants ate the protein and vegetable portions of a meal before the carb portion compared to when they ate all of the components mixed together. If you don’t have diabetes, your blood sugar spikes are likely to be less pronounced so you may see less of an effect.
Say your lunch consists of rice, chicken, and vegetables. Before digging in, make sure you eat the chicken first, followed by the vegetables, and then finish off with the rice. What if your meal consists of multiple components that are mixed together (think a burrito, sandwich, bowl of soup, plate of pasta, etc.)? Do your best to wait to eat the starchy, carby component until last.
- Eat the chicken first, followed by the vegetables, and then finish off with the rice.
- For a burrito, sandwich, bowl of soup or plate of pasta, do your best to wait to eat the starchy, carby component until last.
Habit 2: Walk 10 to 15 Minutes After a Meal
Movement helps control glucose levels because when muscles contract, they use glucose for energy. That reduces the body’s need for insulin.
Take it from scientists who studied the impact of exercise on glucose control. In a 2016 study, 41 adults with type 2 diabetes were asked to go for a 10-minute walk after each meal. Compared with taking a 30-minute walk at any point during the day, the shorter post-meal walks reduced overall glucose levels after meals by around 12 percent, and after dinner by 22 percent.
That’s not all. When researchers reviewed a slew of studies in 2022, mostly in overweight adults, they found that on average, breaks for light walking reduced glucose levels after meals by about 17 percent, compared with sitting. (Standing breaks reduced blood glucose by about 9.5 percent on average.)
So when you’re feeling sluggish, it may be time to get up and move. Tomorrow after lunch, instead of sitting down right away, try strolling around the block for 10 to 15 minutes. You may be surprised by the impact it has on your energy, even if you stroll at an easy pace.
- Tomorrow after lunch, instead of sitting down right away, try strolling around the block for 10 to 15 minutes.
- An easy pace counts.
Habit 3: Pair Carbohydrate With Protein or Fat
When you have a carb, have a protein or fat with it: cheese and crackers instead of just crackers, fruit and yogurt or nuts instead of just fruit, and toast and eggs or nut butter instead of just toast and jam (fat may blunt the spike but the overall spike may last longer, since a flatter spike doesn’t necessarily equate to a shorter spike).
Adding protein or fat to a meal or snack that’s carb-heavy slows the emptying of your stomach and causes your insulin to rise earlier. Thus, your glucose gets into your bloodstream more slowly instead of all at once. One study found that 15 people with well-controlled type 2 diabetes who drank a protein (whey) drink before eating a sugary meal (in this case, white bread with jelly) experienced 28% lower glucose levels over three hours following the meal and about 96% higher insulin levels shortly after eating.
- Cheese and crackers instead of just crackers.
- Fruit and yogurt or nuts instead of just fruit.
- Toast and eggs or nut butter instead of just toast and jam.
Habit 4: Sleep
Sleep deprivation has been linked to poor glycemic control. Inadequate or insufficient sleep may cause you to be less efficient at clearing glucose the following day and may lead to higher and more prolonged blood glucose levels after meals. Poor sleep may also make your body less responsive to insulin (insulin resistance), meaning it has a harder time getting sugar out of the bloodstream. In one study of nine healthy adults, researchers found that insulin sensitivity was decreased by 19 to 25% after one sleep-deprived (four hours of sleep) night when compared to a full night of sleep.
Although this study looked at one significantly sleep-deprived night, smaller variations in sleep quality and quantity have been shown to affect the body’s ability to efficiently utilize glucose. Practicing good sleep hygiene, such as going to bed and waking up at the same time every day and avoiding electronic devices one hour before going to sleep, can help promote restorative sleep.
- Go to bed and wake up at the same time every day.
- Avoid electronic devices one hour before going to sleep.
Habit 5: Resistance Exercise
Resistance exercise has been shown to reduce blood glucose spikes in two different ways. When muscles contract, they pull glucose out of the blood, so resistance exercise done around the time of a meal can reduce the glucose spike from that meal. In addition, having more muscle mass improves insulin sensitivity and increases your muscles’ ability to remove glucose from the blood after a meal, so over time, resistance training leads to better control of blood sugar spikes.
A 2014 study in nine insulin-resistant adults showed that a moderate-intensity, 30-minute walk taken before dinner didn’t do much to control blood sugar, but when the same group took six one-minute breaks to walk briskly on an incline treadmill (vigorous-intensity exercise), starting 30 minutes before each meal, their average blood glucose over the following 24 hours dropped by about 13 milligrams per deciliter (mg/dL), and the positive effect lasted into the following day. In another variation of the study, three of the six one-minute vigorous-intensity bouts were replaced with resistance exercise, with similar results. The takeaway is that vigorous exercise using the large muscles in your body helps them remove glucose from the blood.
- Six one-minute breaks to walk briskly on an incline treadmill, starting 30 minutes before each meal.
- Three of the six bouts can be replaced with resistance exercise, with similar results.
The Five at a Glance
Eat protein and veg before carbs when possible, walk for 10 to 15 minutes after eating, pair carbs with fat or protein, sleep well, and lift weights or do incline walking before meals. Whether or not you have diabetes, leveling out the curve will likely help your energy levels throughout the day, preventing crashing (and feeling hungry again) just two to three hours after you eat. Try just one of these for a week and see if it changes how you feel in the afternoon.
What This Does Not Replace
Diabetes is a medical condition that requires monitoring and treatment from a qualified health care professional. These strategies aren’t a substitute for that care, nor should you alter, put off or forgo any medications or treatments your health care provider has recommended without speaking with them first. Keep checking your blood sugar, whether that’s finger sticks, a sensor, an A1C or some other means, as your provider directs.
If you’re not living with diabetes but you’re concerned about repeated high blood sugar, talk with your health care provider. They may suggest you get a two-hour glucose tolerance test and then follow up after that.
Stephanie Wright, RN, BSN, is a Registered Nurse with more than 15 years of experience in critical care, mental health, managed care, and clinical leadership.
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