Common Causes of Blood Sugar Spikes

Good fiber-rich foods include:

• Apples and bananas 
• Oats 
• Peas 
• Black beans and lima beans
• Brussels sprouts 
• Avocados 
• Wheat flour and bran
• Nuts and seeds

Eat a healthy dinner, too. Blood sugar is usually the hardest to control later in the day. That’s why many experts say you should choose a dinner or after-dinner snack low in carbohydrates, especially the processed kind. Fat and protein don’t cause blood sugar to rise the same way carbs do. If you’re not sure how to balance your meals, ask your doctor for a referral to a dietitian who specializes in diabetes.

Plan when you eat. If you have diabetes or prediabetes, having meals and snacks too close together may not give your blood sugar level time to drop naturally after you eat. Make sure your meals are four to five hours apart. If you need a snack, have it two to three hours after your last meal.

Skipping Breakfast

Start with a good breakfast. If you skip the first meal, your blood sugar is more likely to be too high after lunch and dinner. But don’t just reach for a muffin. One study found that people who ate a 500-calorie breakfast with at least 35% protein had lower post-meal blood sugar throughout the day than those who ate a breakfast lower in protein and higher in carbs.

That’s because protein helps slow your digestion. That makes your blood sugar rise more slowly after meals. And eating fewer carbohydrates means your body makes less blood sugar.

Does oatmeal spike blood sugar?

Yes. But typically only if you eat too much at once, or if you eat instant oatmeal with added sugar. Instead, opt for steel-cut, rolled oats, or instant oatmeal without added sugar. The less processed the oats, the less likely they are to spike your blood sugar.

Too Little Sleep

Not getting enough rest does more than make you groggy. It also affects how well your body can control and break down blood sugar. Skimping on sleep, even for one night, makes your body use insulin less efficiently. That can make your blood sugar higher than it should be.

In one study, researchers asked healthy adults to sleep just four hours a night for six days. At the end of the study, their bodies’ ability to break down glucose was 40% lower on average. Why? Doctors believe that when you enter deep sleep, your nervous system slows down and your brain uses less blood sugar.

Get your shuteye. Remember all the things that help: Stick to a regular schedule, don't use your phone or tablet close to bedtime, and relax before you hit the hay.

Too Much (or Too Little) Exercise

Even a mild workout, such as walking or doing light housework, can lower your blood sugar and improve how your body responds to insulin. Research shows that a 15-minute stroll after dinner can help bring blood sugar down. Even better — it can help keep it down for up to three hours. When you exercise, your body pumps more sugar to your muscles.

When you don’t move around enough, your glucose levels can rise. Too much exercise can have the same effect. Tough activities, such as bench-pressing weights, or competitive ones, like running a race, can raise your blood sugar.

That doesn’t mean you can’t sweat it out. Exercise is one of the best things you can do for your whole body. But ask your doctor what changes you may need to make in your treatment plan to keep your blood sugar in the right range.

Stress

When you’re really under pressure, your body releases hormones like cortisol and adrenaline. This is known as your fight-or-flight response. It prompts your body to act like it’s under attack.

Your body burns its stored energy sources — glucose and fat — to meet the threat. When you have diabetes, insulin can’t break through the cells to break down the glucose, and your blood sugar rises.

Stress can also cause blood sugar to rise indirectly. You may be less likely to take care of yourself by eating right, exercising, or taking your medicine when you’re stressed out.

Because you can’t avoid all stress, finding ways to relax is good for your blood sugar and your overall health. Try meditation, yoga, or massage.

Some Medications

Insulin is your body's natural way to control blood sugar. But if you have diabetes, your body doesn't make insulin, and you need to use insulin to control your blood sugar.

But other drugs, such as corticosteroids, can cause your blood sugar to spike. 

Here are some medicines that can cause blood sugar spikes: 

• Diuretics (“water pills”)
• Drugs used to treat depression
• Blood pressure medicines

If you’re on any of these medicines and you notice your blood sugar is high, talk to your doctor. They may adjust your diet or medications.

Not Brushing and Flossing

If you have diabetes, you’re more likely to get gum disease (also known as gingivitis). And serious gum disease can make it harder to keep your blood sugar under control. Like all infections, it may cause your glucose to rise. That, in turn, can make other infections more likely. Inflamed or infected gums can also cause your body’s defense system to go into overdrive. That makes it harder for your body to keep insulin and blood sugar in check.

Make sure you not only brush and floss your teeth but also rinse with an antiseptic mouthwash daily.

Keep up with your dentist visits and work on managing your blood sugar. And if you have gum disease or any other infection in any part of your body, treat it ASAP.

Smoking

If you light up, you raise your chances of getting diabetes. If you already have diabetes, you’re more likely to have trouble finding the right dose of insulin and controlling your blood sugar. Smoking makes it harder to keep your blood sugar levels down.

The lesson here: If you smoke, quit.

Dehydration

Drink plenty of water. When you’re dehydrated, your glucose may be higher than it would normally be.

Menstrual Cycle

Menstrual cycles are different for everybody, but when you get your period, your body can have high and low blood glucose levels because it reacts differently to insulin. Here's why.

Your cycle occurs in phases, including: 

• Menstrual phase
• Follicular phase
• Ovulation
• Luteal phase

Your hormones fluctuate during those phases to help prepare your body for pregnancy, including the luteal phase, when progesterone rises and estrogen declines. For some people, these higher levels of progesterone can cause insulin resistance and cravings for foods such as chocolate and sugary sweets. If you're not careful, this can cause blood sugar spikes even when you're eating right and exercising. 

The Apple Women’s Health Study found that participants had healthier blood sugar levels during the follicular phase. Researchers looked at data from 231 study participants and found that they had a healthy blood sugar level for 68.5% of the day during the follicular phase compared to 66.8% of the day while in the luteal phase. Researchers also showed that participants had fewer spikes in blood sugar while in the follicular phase than in the luteal phase. 

The bottom line is menstrual cycles can affect blood glucose levels, but the timing, extent, and exact impact can vary. So, we need more research to definitely say how much your blood sugar will increase during your period.

Do Artificial Sweeteners Raise Blood Sugar Levels?

Artificial, or non-sugar sweeteners (NSS) were created as alternatives to sugar and popular ones include: 

• Advantame
• Aspartame 
• Acesulfame potassium
• Neotame
• Saccharin
• Sucralose

They're added to food and drinks during production, or directly by consumers. 

Traditionally, they were thought to be the only sweetener options for people with diabetes, as many older studies found they didn't have any effect on your body or health. But researchers are just beginning to understand how these sweeteners affect our blood glucose levels.

This means we need more research to truly understand if, and how, artificial sweeteners can raise your blood sugar, especially if you use them for long-term consumption.

How to Avoid Blood Sugar Spikes

You can avoid blood sugar spikes by doing a few simple things, including:

• Limit foods you eat that are high in carbohydrates and sugars.
• When you eat carbs, pair them with proteins (such as apples and peanut butter or hummus and veggies).
• Drink plenty of water and limit alcohol.
• Take a walk after you eat.
• Don't eat sugary sweets on an empty stomach.

Takeaways

Many things can cause your blood sugar to spike, not just foods. Stress, dehydration, smoking, and lack of sleep are just a few things that can send your blood sugar soaring. Even poor dental hygiene can affect your blood sugar. But all of these are manageable and can help you avoid blood sugar spikes if you just make a few lifestyle changes.

Blood Sugar Spike FAQs

What happens if the blood glucose test is high?

A blood glucose level of 140-199 milligrams/deciliter is considered high. That could mean you have prediabetes and are at a higher risk of diabetes. You might not have any symptoms, but you should talk to your doctor or health care provider to be sure. 

What are the 5 worst foods for blood sugar?

It's hard to nail down five foods that would be labeled the worst for your blood sugar. But foods you should avoid when you're concerned about blood sugar spikes would include:

• Fast food
• Sugary drinks, including specialty coffees and fruit juices
• Processed meats such as hot dogs
• Fried food
• Whole milk