Let’s talk about blood sugar, or blood glucose. Maybe you’ve been diagnosed with diabetes or prediabetes and you’re not sure where to start. Or maybe you’ve just been hearing some buzz about “blood sugar-friendly foods” and you’re wondering if you should pay attention.
When blood sugar spikes after eating, it can leave you feeling tired, lethargic and moody. Over time, chronic blood sugar issues can put you at risk for conditions like kidney disease, heart disease and even dementia.
The good news is, you can improve your blood sugar control today with a few simple steps.
What causes blood sugar spikes?
First, let me define what a blood sugar spike is and how it happens. A blood sugar spike occurs when your blood glucose level rises right after eating. This is actually a normal occurrence in all people after eating foods that contain carbohydrates. When this happens, two important reactions take place in the pancreas: an immediate release of insulin and an immediate release of a hormone called amylin.
Insulin works quickly to move glucose out of the bloodstream and into cells. This takes just a matter of minutes. The amylin helps prevent food from reaching the small intestine too fast (where most nutrients are absorbed). Most of the time, the after-meal blood glucose rise is temporary, even hardly noticeable.
But for people with diabetes, these normal post-meal reactions are hampered. In people with Type 2 diabetes, the pancreas makes insulin, but the cells don’t respond to it as they should. This is referred to as insulin resistance.
Since the glucose can’t get into cells, the blood sugar level quickly rises. Diabetics (Type 1 or Type 2) who are on insulin therapy typically experience a significant delay in the reduction of blood sugar because it can take up to 15 minutes for the insulin to begin working. Diabetics also either do not produce amylin at all, or not in sufficient quantities. This causes their food to be digested much faster.
As a result of delayed insulin release and a faster digestion rate, blood sugar levels can rise very high right after eating. Once the insulin finally kicks in, a rapid drop in blood sugar can occur.
How these blood sugar spikes affect your health
Over time, recurrent spikes in after-meal blood sugars, can raise your HbA1c level. HbA1c is a measure of your average blood sugar over a three-month period. Having an elevated HbA1c has been shown to increase the risk of other health complications.
Research has shown that frequent high blood sugar levels after a meal can exacerbate the onset of kidney disease and accelerate the progression of retinopathy. Type 2 diabetics may experience more cardiovascular problems when post-meal blood sugar spikes occur frequently.
Cognitive decline, including an increased risk of dementia, has also been associated with after-meal sugar spikes and large variations in blood sugar levels. Other short-term complications can include fatigue, cognitive impairment (also called brain fog), reduced physical ability and changes in mood.
One study conducted on the effects of acute high blood sugar on cognitive function and mood in type 2 diabetics found that the speed of information processing, memory, and some features of attention were all impaired during elevated blood sugar readings. It was also noted that participants experienced a reduction in energy and increased sadness and anxiety.
Preventing after-meal blood sugar spikes
Reducing after-meal blood sugar spikes can be achieved with medication management and dietary changes. First and foremost, for anyone looking to change their diabetes medication or insulin therapy, it is imperative to consult with your primary care physician or diabetes specialist.
Ensuring that you are on the best medication treatment plan can significantly improve your ability to control after-meal sugar spikes. However, medicine is only one piece of the puzzle to controlling blood sugar. Diet and exercise play a big role too.
Here are my top lifestyle tips to help you maintain healthy blood sugar levels.
1. Limit foods that have a high glycemic index (GI)
GI is a measure of how fast a food can cause blood sugar to rise. A GI score is rated between 0 to 100. Foods that have a high GI are often high in processed carbohydrates and sugars, are quickly digested and absorbed, and can cause a rapid rise in blood sugar. For example, pretzels have a GI of 83.
Foods with a low GI are broken down at a slower rate and cause a slower rise in blood sugar. Low GI foods are typically high in fiber, protein, and/or fat. Apples, for example, have a GI of 28 and peanuts have a GI of 7.
In general, eating more low glycemic index foods may help reduce after-meal sugar spikes. Use this guide for help replacing high GI foods with low GI foods.
2. Eat more fiber
Another dietary adjustment to lower blood sugar spikes is eating more high-fiber foods. Besides helping with digestion and lowering cholesterol, fiber-rich foods contain slow-digesting carbohydrates. These carbohydrates help block elevations in blood sugar after eating because fiber takes longer to digest in your intestines. This allows a slower release of glucose into your bloodstream.
Good sources of fiber include beans, whole grains and fruit. Increasing your overall fiber intake may help keep your after-meal blood sugars down. Here are some quick and easy tips to increase your fiber intake:
- Try a small bowl of oatmeal for breakfast with an ounce of nuts and fresh or frozen berries.
- Throw some beans on top of your salad or include them in a wrap for lunch.
- Add a small sweet potato (microwaves in less than 10 minutes) or a pouch of ready rice/grains such as brown rice or quinoa.
- Snack on roasted chickpeas or a sliced apple or pear (leave the skin on).
3. Make smart food pairings
Meal composition also matters when trying to control blood sugar spikes. Ensuring your meals and snacks contain an appropriate ratio of carbohydrates, proteins and fats is the key.
Eating only large portions of carbohydrate-rich foods at meals or snacks causes too much sugar to be released into the bloodstream. Because proteins and fats take longer to digest than carbs, pairing carbohydrates with proteins and/or fats can help keep your blood sugar steady, slowing down digestion and absorption in the intestines. This, in turn, will slow the rate of sugar entering the bloodstream.
For example, pick a healthy carb option and a healthy protein option from the table below to make a blood sugar friendly snack.
|Handful of nuts||Whole fruit (apple, ½ banana)|
|1 cup Greek yogurt||5 whole wheat crackers|
|2 deli turkey slices||1 whole grain tortilla|
|1 oz beef jerky||1 oz whole wheat pretzels|
|Hard-boiled egg||1 cup regular yogurt|
|½ cup cottage cheese||¼ cup granola|
|1 tbsp peanut butter||3 cups popcorn|
|2 tbsp hummus||½ cup dried fruit|
|1 oz cheese||1 cup raw vegetables|
4. Reduce portion sizes
Reducing the portion of your meal can also help. The amount of food you eat has a great impact on your blood sugar. Using smaller plates and bowls, or splitting your meal in two can reduce your portions. You can store the leftover portion for a snack an hour or two later or for a meal later in the day.
5. Move after eating
Exercising or being active soon after eating will also lower your blood sugar in many ways. First of all, the glucose that doesn’t enter the bloodstream can be used for muscle use during exercise.
Exercise also diverts blood flow away from the intestines, reducing glucose absorption. If you take insulin before a meal or snack, exercise will increase blood flow to the skin surface, allowing the insulin to absorb and act more quickly.
It doesn’t take a lot of exercise to produce a drop in post-meal blood glucose levels. One study showed that just 15 minutes of walking after meals significantly improved glycemic control over a 24-hour period. Furthermore, a short post-meal walk was significantly more effective than a 45-minute sustained walk in lowering 3-hour post-meal glucose.
Here are a few easy ways to get moving after a meal:
- Avoid sitting for long periods of time after eating.
- Avoid reading, watching TV or working on the computer after meals or snacks.
- Try going for a walk or walking the dog.
- Do a few chores.
- Go shopping.
- Use a standing desk while working after meals.
- Schedule longer exercise sessions for after meals that typically cause higher blood sugar spikes.
6. Prevent low blood sugar
An often-overlooked way to prevent blood sugar spikes after meals is to prevent any hypoglycemic episodes. Hypoglycemia, or low blood sugar, can happen when you don’t have enough sugar in your blood.
For most people, hypoglycemia is a blood sugar level below 70 milligrams per deciliter (mg/dL). Common causes of low blood sugar include taking too much insulin, skipping meals, not eating enough or exercising more than usual.
A side effect of hypoglycemia is that it speeds up the rate at which the stomach empties. Therefore, when food is consumed, it’s digested more rapidly, causing a blood sugar spike. Preventing hypoglycemia is the best way to avoid this type of blood sugar spike.
Worried about your blood sugar?
Controlling after-meal blood sugar spikes is possible with a little extra planning! Keeping your blood sugars balanced can help keep you more energized during the day and reduce the risk of developing complications later on.
If you’re worried about your HbA1c or blood sugar control, talk to your doctor or find diabetes support near you.
About the author
Lisa Marsh, MS, RD, LD, CNSC, is a clinical dietitian with the Baylor Scott & White HealthTexas Provider Network. She provides nutrition assessment and dietary counseling for the Personal Edge Executive Wellness Program and Signature Medicine. Lisa's professional interests include nutrition counseling and consultation for the treatment of diseases and conditions related to an individual's diet and eating behaviors. Lisa's methods are geared toward lifestyle and behavioral changes unique to each individual.