Avoid Hangry: How to prevent and treat low blood sugar

apple with peanut butter

(Healthcastle.com) Every felt weak, clammy, dizzy or even just plain irritable in between meals? Did it disappear when you ate? Low blood sugar, otherwise known in medical circles as hypoglycemia, is an unpleasant experience. Preventing too low blood sugar is relatively easy - but it does require a bit of planning and a balanced plate. Find out how to prevent it from happening and stabilize your energy and mood while you're at it!

What is hypoglycemia?

Hypoglycemia in the strictest sense is a blood glucose of less than 4 mmol/L. You don't need to test your blood sugar to really know if its happening. Most of us feel it, some more than others. 

If your blood sugar is too low, you might experience some of these symptoms: 

  • Trembling or weakness
  • Dizziness
  • Palpitations
  • Clammy or sweating (most often described as a "cold sweat")
  • Anxiety, confusion or trouble concentrating
  • Hunger
  • Nausea
  • Headache
  • Irritable, angry or grouchy for no real reason (otherwise known as hangry!)
  • Fainting or loss of consciousness

While low blood sugars aren't as imminently damaging on your body as high blood sugars, they still instigate a stress response. In our over-stressed world its best to try and minimize these episodes so our bodies can heal from everyday assaults. 

Why does it happen?

 Blood sugar management is a reeeeallly complex system. We're still unraveling some strands of the story but it generally happens one of four ways.

  1. We haven't taken in enough carbohydrates from food (such as going long periods between meals)
  2. We burned through our easy access reserves in the muscle and liver (such as long or intense exercise)
  3. We "put away" more glucose in to storage, leaving less than we need in the blood. This is usually associated with eating higher glycemic index meals and large doses of refined carbohydrates that lead to spikes of insulin trying to put away all the excess. Sometimes our bodies seem to overshoot the insulin needed and we end up with clammy hands and a grumbling stomach. 
  4. Diabetic medications, alcohol and some other drugs may cause lower than usual blood sugars. Alcohol in particular can be tricky as the hypoglycemia is often delayed. Fun fact - this often contributes to the clammy, nauseated, weak sensation you get with a hangover! 

What can you do? 


If you are already feeling low- find a refined carbohydrate (piece of white bread) or something sugary ( 1/2 cup of pure juice is a good option). Wait 15 minutes after having this. If you're feeling better, follow it up a snack that has some fibre, complex carbohydrates and a bit of fat. A piece of sprouted grain bread with a spoonful of peanut butter or an apple with a slice or two of cheese are both good picks to help stabilize your now normal blood sugar.  


Prevention is really the key here. We'll do this by keeping our carbohydrate portions sensible and by making them last by slowing digestion and absorption so you get more of a trickle of sugar in the blood, not an avalanche. Side bonus- this is also the best way to boost your energy and avoid mid afternoon slumps!

  • Avoid processed and refined carbohydrates and sugary treats as a general rule. When you do have them pair them with a light but high fibre and balanced meal (like a big, hearty salad to start) to avoid both blood sugar highs and lows. 
  • Don't forget to have a healthy portion of protein at each meal. We actually convert 20-30% of the protein we eat in to glucose, so its a built in slow release blood sugar stabilizer. By including this and keeping the more easily digested carbs in a much smaller portion you'll feel much steadier during the day. 
  • Keep carbohydrate portions moderate and make sure they are high quality. Slow digesting fruit, whole or sprouted grains, or starchy root veggies are all good choices that will stick with you over several hours and prevent blood sugar spikes that lead to crashes later on. 
  • Balance your meals and snacks- high fibre fruits and veggies are key to slowing down digestion and absorption, as is a bit of fat in the form of avocado, olive oil, nuts/seeds, or a slice of cheese. 
  • Veggie up! I can't emphasize enough how much this help. Veggies provide fullness, fibre and the micronutrients needed to help your body perform at its best. Big salads, cauliflower rice, roasted goodies- make sure you're getting at least a half a plate full at lunch and dinner. 
  • Don't forget to balance breakfast! My patients often overlook this crucial starting point. Have a piece of fruit, low to moderate portion of unprocessed complex carbs (oats, sprouted whole grain bread) and a protein (eggs, leftover chicken or meat, plain greek yogurt, nuts or a protein powder). 

When to get help

  • Check in with your doctor and your dietitian if any of the following sound like you: 
  • If you experiencing times when you are close to, or are actually fainting
  • You are struggling to make the right choices to keep your blood sugar balanced due to knowledge, cooking skills, time or energy
  • You are following the prevention plan well and are still experiencing symptoms. Some types of more low blood sugar are driven by medical issues (such as reactive hypoglycemia, certain drugs, insulinomas). These are uncommon but do need medical attention if they are happening. 


CDA practice guidelines reference


Photo by Melissa

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