5 things everyone needs to know about blood sugar (even if you're not diabetic)

June 18, 2020

Whether you have diabetes or not, you should still take care of your blood sugar levels. Here’s why.

How your blood sugar changes when you eat is a crucial indicator of your health. In this post, we share 5 things you need to know about blood sugar control (whether you have diabetes or not):

  • Everyone’s blood sugar changes after they eat
  • Maintaining healthy blood sugar levels is vital for health
  • Unhealthy blood sugar responses after eating can damage your health in the long term
  • A one-size-fits-all low carb diet won’t work for everyone
  • To maintain healthy blood sugar levels, you need to understand your own unique responses to food

1. Everyone's blood sugar changes after they eat

When you eat, the food makes its way down into your stomach where the digestion process begins. Then the partially digested food passes into your intestines, where enzymes continue to break down the components of your food into smaller building blocks. 

Carbohydrates in your food are broken down into sugar (or glucose if you want to be more scientific), which passes through the walls of your intestines and into your blood. Once the sugar from your food enters your blood, it is transported around the body to wherever it’s needed. 

Glucose is absorbed the lumen of the small intestine into the bloodstream.


2. Maintaining healthy blood sugar levels is vital for health

High blood sugar can be toxic, damaging your cells and causing inflammation. But low blood sugar means your body won’t have the energy it needs to function, making you feel tired and hungry. Very high and very low blood sugar are both extremely dangerous, but even more moderately unhealthy glucose responses can lead to health problems.

Unhealthy blood sugar responses after eating have been linked to an increased risk of developing type 2 diabetes, having a heart attack or stroke, and even developing certain types of cancer. So maintaining your blood sugar levels is a crucial part of staying healthy.

3. Unhealthy blood sugar responses after eating can damage your health in the long term

But what does a healthy or unhealthy blood sugar response look like?

We all have increased blood sugar after we eat. It’s the job of a long, flat organ called the pancreas, tucked just behind your stomach, to sense the amount of sugar in your bloodstream and act if the levels get too high or too low. 

When your blood sugar levels start to rise, your pancreas produces insulin. Insulin is a hormone that encourages your cells to take up more sugar, helping your blood sugar levels return to a level that’s normal for you (sometime known as ‘baseline’).

The differences between a ‘healthy’ or ‘unhealthy’ response are about how high your blood sugar goes after you eat, how long it stays high, and whether your blood sugar dips below baseline before stabilizing. 

An example of what a 'healthy' and 'unhealthy' blood glucose response looks like after eating a meal.

How can you measure your blood sugar?

There are a few different ways to monitor your blood sugar:

  • Fasting blood sugar – This a simple blood test that measures the amount of glucose in your bloodstream first thing in the morning before you eat. While this test reveals your fasting baseline, it doesn’t tell you anything about what happens to your blood sugar after you eat.
  • HbA1c test – This is a blood test that measures the levels of HbA1c, a molecule in the blood that binds to glucose. This gives an indication of average blood glucose levels over the past few weeks, but it can’t tell you about your responses to individual foods. 
  • Measuring your blood sugar at a set time after eating – This provides a snapshot of your blood sugar after eating a particular food but doesn’t give you a comprehensive view of what is happening over a longer period of time. 
  • Continuous glucose monitoring – This is done using a wearable device that sticks to the skin and measures the sugar in your blood continuously over a period of up to 6 days. This is the gold standard for understanding how the body responds to food, and it’s the method we use in our PREDICT studies. 

4. A one-size-fits-all low carb diet won’t work for everyone

Several diets designed to combat unhealthy blood sugar responses have been created in recent years. They have been publicized as ‘the’ way to lose weight, avoid chronic diseases, and support your health. But do these blood sugar diets work? 

Most ‘blood sugar diets’ are low-carbohydrate diets. They claim to control your blood sugar by reducing unhealthy responses to food and preventing blood sugar spikes. 

Some fans of these diets point to studies where low-carbohydrate diets have improved blood sugar control in the majority of the participants.

But here’s the catch: you are not the majority of people. You are you.

5. To maintain healthy blood sugar levels, you need to understand your own unique responses to food

Research is increasingly showing that while some people respond better to a low-carbohydrate diet, others are better off on a low-fat, high-carbohydrate diet

Our PREDICT studies have found that even identical twins, who share all their genes, can have very different responses to the same foods. 

That means that a diet that helps one person may not be right for you and could even be unhealthy. Improving your nutritional responses is not as simple as eating a particular prescribed diet or sticking to foods labelled as 'good for your blood sugar.'

Keeping your blood sugar healthy is all about eating the foods that you respond to best. To do that, you need to understand how your metabolism responds to different food  - your ideal diet is the one that works best for you.

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