low blood sugar and energy levels

How Low Blood Sugar Affects Your Body

Sugar crashes aren’t just for toddlers. Adults get grumpy and hangry too. When your blood sugar level dips below normal levels, the energy drain and tiredness can be all too real. But what’s the relationship between sugar intake and energy levels? Are there any “good sugars”?

Hydrant dove into the literature to find out what’s actually going on when we feel low energy, and how to best recover with a sugary pick-me-up.



Blood sugar level 

Every cell in your body uses sugar, more specifically glucose, to generate the energy it needs to survive. It’s crucial to consume sugars in our diet so that we can keep enough glucose in our blood to supply every cell.

Low Blood Sugar (Hypoglycaemia) and Energy Levels

Our blood sugar levels are carefully controlled to regulate the amount of glucose available to our cells. Too high or too low are both dangerous. We need our blood sugar levels to be just right to be at our best. When blood sugar levels rise, the pancreas (a small organ that sits behind the stomach) responds by secreting insulin. Insulin is a hormone that stimulates the cells of the body to take up glucose from the bloodstream, lowering blood sugar levels again. People with diabetes need to inject insulin as they can’t produce or respond to their own insulin effectively.

As blood sugar levels drop, the pancreas no longer produces insulin and instead produces the hormone glucagon. Liver cells respond to glucagon by releasing stored glucose into the blood to raise blood sugar levels back to a normal range.



Low Blood Sugar (Hypoglycaemia) and Energy Levels 

Normal blood sugar levels range between 70-140 mg of glucose per deciliter of blood [1]. More extreme dips in blood sugar level – below 55 mg/dL – are known as hypoglycemia [2]. Signs of low blood sugar include sweating, dizziness, tiredness, or even collapsing. Since the symptoms result from a lack of blood glucose, they can often be treated by having a sugary snack or eating a meal [3].

Hypoglycemia is generally experienced by people with diabetes and can be caused by changes in insulin injections, diet, or exercise [3].

Although rare, non-diabetics can also experience hypoglycemia. This may take the form of reactive hypoglycemia, which happens within a few hours of eating a meal or fasting hypoglycemia, which may be related to a disease [4]. Reactive hypoglycemia is not fully understood but is thought to be caused by an abnormal spike in insulin after eating. The underlying cause may therefore be pre-diabetes, although other possible causes include stomach surgery and rare enzyme deficiencies [4]. Fasting hypoglycemia can be caused by certain medicines, illnesses, or tumors. Fasting hypoglycemia may also be caused by consistent alcohol consumption due to alcohol’s ability to prevent the liver from making new glucose to replenish dropping blood sugar levels [4]. The likelihood is increased when alcohol is consumed in the setting of poor nutrition and depleted glucose stores [2].



Glycemic index and load

When we think of sugar, we often imagine the white crystals spooned into coffee or cakes. However, sugar enters our diet in many forms. The term carbohydrate includes sugars, as well as more complex molecules that can be broken down into sugars in our digestive systems. However, not all carbs are created equal and different carbohydrates can have different effects on our blood sugar when we consume them.

Low Blood Sugar (Hypoglycaemia) and Energy Levels

One way to classify carbohydrates is “simple” vs “complex.” Simple carbohydrates are composed of simple sugar molecules such as glucose and fructose. When eaten, simple carbohydrates quickly lead to a rise in blood sugar. Complex carbohydrates contain many sugar molecules linked together – since they have to be broken down into individual sugars, they tend to cause a slower rise in blood sugar [5].

Carbohydrates can be directly classified by their ability to raise blood sugar by ranking them in the glycaemic index. If a food has a high glycaemic index (closer to 100), such as white bread, it is digested quickly and causes a fast spike in blood sugar level. Foods with low glycaemic index (below 50) take longer to digest so their effect on blood sugar is more graduated. Even within the same food glycaemic index can change – for example, ripe fruits and vegetables have a higher glycaemic index than their unripe counterparts. [5]

Carbohydrates may also be described by their glycemic load. This metric takes into account the amount of carbohydrate in the food as well as its impact on blood sugar levels. The more carbohydrates a food contains and the higher the glycemic index of a food, the higher its glycemic load will also be [5].



What does high blood sugar do to energy levels?

Thus far, this article gives the impression that if you’re feeling low energy, a sugary snack might be the solution. Certainly, if you’re suffering from hypoglycemia that might be the case. As mentioned before, however, this condition is fairly rare in non-diabetics. 

But is lots of sugar going to leave you with a pep in your step all day long? Unfortunately, the answer is possibly no. A study of 82 adults showed that those who were given a high glycaemic load diet (i.e. one with lots of carbohydrates that are rapidly digested to give fast spikes in blood sugar) reported feeling more fatigue than participants on a low glycaemic load diet [6]. This study is small and investigated energy levels in the context of low mood and depression, but it still hints that more sugar does not always equal more energy.



Other ways to boost energy 

Sugar is vital...at the right amount. Like most things, enjoy sugar in moderation. Low blood sugar (hypoglycemia) may cause tiredness. We need to intake enough sugar to keep blood glucose levels up. On the flip side, however, eating too much sugar and/or consuming high glycemic index foods may also cause fatigue. Healthy diets demand the right balance of sugar.

Blood sugar and energy

Blood sugar isn’t the be-all and end-all of energy levels. A variety of lifestyle measures such as sleep, exercise, and stress can affect the spring in your step. Within the diet, certain vitamin deficiencies (e.g. magnesium) may also cause low energy levels [7]. This is not even to mention the range of chronic and acute diseases that can impact energy levels. It’s important to take into account your lifestyle, diet, and health when considering how best to boost energy levels. 

For a quick pick-me-up, reach for your daily dose of Hydrant. The Hydrant mix features the right balance of sugars and salts to get you back to an even keel. Hydrant isn’t a sugar rush or a hit of caffeine; instead, it gets you back in action by delivering effective hydration.

Writer: Josie Elliott
Editor: Elizabeth Trelstad, www.hellobeaker.com



[1] WebMD. “What are normal blood sugar levels?” Oct 2018. - A quick answer to “what are normal blood sugar levels?”
[2] M Desimone and R Weinstock. “Non-Diabetic Hypoglycemia.” NCBI. 2017. - A medical text that describes the pathology and treatment of hypoglycemia.
[3] NHS. “Low blood sugar (hypoglycaemia).” Aug 2017. - This informational page from the UK’s National Health Service details the symptoms, treatments, and causes of hypoglycemia.
[4] M. Eckert-Norton and S. Kirk. “Non-diabetic hypoglycemia.” The Journal of Clinical Endocrinology & Metabolism. Oct 2013. - An article that discusses the causes, symptoms, diagnosis, and treatment of non-diabetic hypoglycemia.
[5] Harvard T.H. Chan. “The Nutrition Source: Carbohydrates and Blood Sugar.” - An accessible guide to the different types of carbohydrates and how each type changes blood sugar levels.
[6] K Breymeyer et al., “Subjective Mood and Energy Levels of Healthy Weight and Overweight/Obese Healthy Adults on High- and Low-Glycemic Load Experimental Diets.” Appetite. NCBI. Dec 2016. - This study investigated the effect of diet on mood and energy levels and found that adults on higher glycemic load diets reported increased fatigue and lower mood.
[7] United States Department of Agriculture. “Lack Energy? Maybe It’s Your Magnesium Level.” R. Bliss. May 2004. - A short article describing the results of study linking magnesium levels to energy metabolism.
[8]. Best Electrolyte Powders is a website with a just-the-facts comparison between the five big electrolyte powder brands

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