Nutrition 1/22/2021

What is blood sugar?

What is blood sugar?

In this course, you will learn what blood sugar is and why it's so important for your body to control the sugar in your blood.

39 Cards

If you have diabetes or know someone with diabetes, you know how important it is to control your blood sugar.

Your body likes its blood sugar like Goldilocks likes the height of her chair - not too high or too low, but just right.

You have experience with blood sugar highs and lows, even if you don’t realize it.

Have you ever felt irritable, fatigued or hungry again an hour after eating a stack of pancakes?  Your blood sugar might have soared... and then crashed!

But what is blood sugar?

Swipe to learn about blood sugar and why it’s important to control it.

Blood sugar is what it sounds like - sugar in your bloodstream.  It is the amount of sugar floating around in your blood.

Where does this sugar come from?  Mostly from food as it gets digested in your stomach and small intestines.  But your liver also produces sugar.

Much of your food is broken down or transformed by your body into the simple sugar glucose, which is the kind that “blood sugar” measures.

A simple sugar is made of carbon, oxygen and hydrogen atoms that join together and often form tiny rings.

Complex carbohydrates (carbs for short), like starches found in many plants, are strings of connected simple sugars.

Your body slowly digests and breaks down carbs like those found in beans and grains into simple sugars like glucose.

Fun Fact: There are some carbs that you can’t digest, like fiber, but that good bacteria in your intestines can eat!

Glucose from digested carbs and sugars gets absorbed from your gut into your bloodstream.

Your blood carries glucose to all of your organs, such as your brain, to power their work.

After you eat, your blood glucose goes up.  Your body must work quickly to use or store this glucose.

Glucose that cells don’t use immediately is stored in your liver and muscles as glycogen.  Glycogen is a string of connected glucose molecules.

Your body can use your glycogen stores for about 12 hours.  Then it has to make its own glucose.

But why is glucose so important?  Why do you need just the right amount of it in your blood?

Glucose is the quickest and most easily used source of energy for your cells.

A cell is a working unit of your body.  Collections of cells form tissues and organs like your brain.

Your cells use DNA at their centers as a recipe book to make proteins.  But this work requires energy.

Your cells prefer to get their energy from glucose, even though most cells can also use other fuels like fats.

For example, your brain cells depend heavily on glucose.  Your brain can’t work without it.

Your red blood cells must have glucose to do the work of shuttling oxygen through your body.

Because your cells are so dependent on glucose, you need some glucose in your blood at all times.

Your liver even breaks down fat and proteins to create glucose when you haven’t eaten in a while.

Low blood sugar or a “crash” can make you feel fatigued, irritable, hungry, shaky, dizzy or faint.

But while too little blood sugar is a problem for your cells, so is too much blood sugar.

Your cells can only take in so much glucose from your blood without risking internal damage.

As cells fill up with glucose, they can start to ignore your body’s signal (a signaling molecule called insulin) to take more in.  This creates high blood sugar.

If your cells continue to ignore your body’s signal to take in more glucose, you can develop insulin resistance.  This leads to lower sugar lows and higher sugar highs.

High blood sugar is a major health concern.  It can cause nerve damage and seizures.

Regularly having high blood sugar after meals can harm your heart and create inflammation in your body.  This puts you at risk for disease and premature aging.

Luckily, your body has many checks and balances to keep your blood sugar level just right.

If you’re healthy with no signs of diabetes, your body is likely very good at controlling your blood sugar.

But there are things you can do to keep your blood sugar levels just right and prevent highs and lows that can harm your health.

Eat more fruits and vegetables! Their fiber forces your gut to digest and absorb sugars from your food more slowly.

Avoid simple sugars like from soft drinks, sugary sweets, white bread and pasta.  Sugars from these foods can hit your system quickly and overwhelm your cells.

Exercise, get enough sleep, manage your stress and take 12-hour eating breaks nightly!  These activities help your cells to use sugar more efficiently.

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