A visual guide to controlling your blood sugar and improving your health

When we eat, our body breaks down food into carbohydrates, proteins, fats and other nutrients.

Carbohydrates are then converted into simple sugar molecules: glucose, which enters the blood through the walls of your intestines.

When blood sugar levels rise, your pancreas releases insulin, which moves glucose into your cells for immediate fuel and into your muscle, liver, or fat cells for storage, where it becomes glycogen, a storage form of sugar. This way the blood sugar level does not get too high.

As cells absorb blood sugar, levels in the blood begin to drop. When blood glucose levels fall too low, the pancreas begins to make glucagon, a hormone that signals the liver to release stored sugars.

The interplay of insulin and glucagon ensures that cells throughout your body, and especially in the brain, have a steady supply of blood sugar.

So it’s normal for your blood glucose levels to rise and then fall again in the hours following a meal. This increase in circulating blood sugar usually begins after about 30 minutes and returns to baseline about two hours later.

However, blood sugar management can become unbalanced and lead to excessive spikes or dips in blood glucose.

These blood sugar spikes can occur in people with metabolic syndrome, a cluster of conditions that occur together, such as obesity, high blood pressure, and high blood sugar. Most people with metabolic syndrome have insulin resistance, which means cells in the body don’t respond to insulin. Their blood sugar levels remain high, which can lead to the development of type 2 diabetes. One in three people over the age of 20 has metabolic syndrome.

People with diabetes also often experience these blood sugar spikes after meals, which can lead to complications. One in five people do not know they have the disease.

According to Sarah Berry, a professor at King’s College London, there isn’t enough research on blood sugar responses in healthy individuals. Many people who have never been diagnosed with prediabetes or diabetes may experience spikes in their blood glucose that reach the diabetic range.

A high spike in glucose in response to eating carbohydrates can cause inflammation. When these spikes are excessive and repetitive, it contributes to adverse low-grade chronic inflammation, atherosclerosis and beta cell degeneration, and can lead to weight gain. These factors are associated with an increased risk of developing obesity, type 2 diabetes, cardiovascular disease and other metabolic diseases. High blood sugar after a meal increases the risk of cardiovascular disease, even in people with normal fasting glucose levels.

Too much blood glucose can also lead to a decreased ability of brain cells to absorb glucose, causing brain fog, a term used to describe mental fatigue and difficulty focusing.

People with dips in their blood sugar may end up feeling hungrier, which can lead to overeating and weight gain. On the other hand, controlling post-meal glucose levels can help reduce food cravings. The drop in glucose levels can cause mood to deteriorate and people to become even angrier.

For healthy people, their concerns may not be health concerns, but they don’t feel quite well after a meal. This differs from person to person. Those who experience high peaks may feel jittery, while big dippers may feel grumpy.

Start with breakfast

What you eat for breakfast can affect your blood sugar for meals later in the day.

“I believe that by having a really high-carb breakfast in the morning, you’re setting yourself up for bigger highs and lows right from the start, which can push some people to keep going on this rollercoaster ride,” says Berry.

Some research shows that those who skip breakfast may have poorer blood sugar and insulin control. However, that may be because people who skip breakfast tend to have poorer diets.

“I believe you should have fat, protein, fiber and carbohydrates in every meal, including your breakfast and all snacks, and not have single-nutrient meals,” said Berry.

Choose a balanced diet

It is important to focus on the overall quality of your food and stick to a balanced diet.

Consider eating less processed foods. It can cause higher glucose spikes and you may feel hungry sooner. These foods are usually high in calories, fat, sugar and salt, but low in fiber, so they are broken down quickly in the body and can cause a rapid rise in blood sugar. They often contain additional ingredients, which are harmful. These foods include frozen meals, packaged snacks, granola bars, soda and some breakfast cereals.

Adding protein and fiber to a meal slows the rate at which your stomach empties and glucose enters the blood more slowly. Certain proteins also trigger the release of insulin, and having more insulin clears glucose faster. Fiber can affect the gut microbiome in a way that also affects glucose metabolism.


Our body is unable to absorb and break down fiber. That means plant foods high in fiber don’t raise blood sugar. When soluble fiber passes through the body, it absorbs water and turns into a gel that slows down digestion and, in particular, the absorption of carbohydrates. Even a modest increase in fiber intake helps lower blood glucose levels.

It is important not only to eat a lot of fiber, but also to have a variety of different plant foods so that your gut microbiome is more diverse. Berry recommends eating 30 different types of plant foods throughout the week.

Some high-fiber options to consider are beans, peas, Brussels sprouts, and broccoli.

Egg white

Swapping pastries for some protein at breakfast can have many benefits. A high protein breakfast can lead to weight loss and better muscle health and can also help improve glucose levels.

In one study, participants ate either a small, high-carb breakfast or a larger, high-protein, high-fat breakfast for three months that provided about 33% of total daily calories. The high-protein, high-fat breakfast group lowered their hemoglobin A1C (a measure of blood glucose levels over three months) and blood pressure.

In another study, people with type 2 diabetes alternated between an omelette and oatmeal for breakfast. On days with the omelet, they then ate less, had less appetite and their glucose levels were more stable throughout the day.

For protein, choosing healthy protein sources like eggs, salmon, chicken, tofu, and beans instead of red meat and processed meats can lower your risk of several diseases and premature death.


Including fats in your diet can improve glycemic control.

Foods that contain saturated fat, especially animal products such as meat, butter and dairy products, may not affect blood sugar levels, but they are detrimental to cardiovascular health. Cut back on foods high in saturated fat, such as sausages, hamburgers, full-fat dairy products, coconut and palm oil, and baked goods, and replace them with foods higher in unsaturated fat, such as olive oil, avocado, salmon, trout, nuts, and seeds can help keep cholesterol levels in a healthy range. Nuts contain compounds that help balance insulin and glucagon, hormones involved in maintaining glucose levels.


Replacing highly processed and refined carbohydrates with whole grains is a great way to increase your fiber intake and keep your glucose levels stable. For example, if you have a piece of toast, consider choosing whole-grain breads with added seeds. Also add some protein and fat. For the toast, add some peanut butter. If you prefer fruit, consider adding some unsweetened yogurt, nuts, and chia seeds.


Exercise causes muscle cells to absorb sugar from the blood, lowering blood sugar levels. Do some squats, push-ups, or sit-ups shortly after meals. Just walking for 10 minutes after eating can also lower the glucose spike. No time to exercise while working at the office? Calf raises while sitting, called the soleus push-up, can also improve blood glucose control.

Individual response

Berry warns against trying to get the glucose levels as flat as possible. It’s also important to keep in mind that people can have a wide range of reactions to many foods.

“I think one thing everyone has to be careful about is that we all react so differently and we see this, especially with glucose,” Berry said. “So what might work for one person might not work for another.”

In one study, when people ate identical foods, such as bread and butter or chocolate, some had significant blood sugar spikes, while others did not. Your genetics, gut microbiome, insulin sensitivity, weight and lifestyle can determine how you respond to different foods. Talk to your doctor to determine what’s best for you.