The glucose machine: how our bodies handle sugar

How Our Bodies Process and Store Glucose

Over the course of millions of years, our bodies have evolved to be extremely efficient sugar using machines. And while that was a big advantage in the palaeolithic, where access to sugars was scarce and people moved a lot in their daily lives, our very sugar-efficient bodies are struggling to keep up with an abundance of sugars in our modern life. As more information about the short- and long-term effects of too much sugar is more readily available, it can be overwhelming to know what is best for your health and diet. In this blog, we want to explore the role of glucose in the body, from the positives to the negatives, as well as the healthy (yes!) ways to eat sugars.

Glucose, a sugar monomer, is key to a healthy metabolism. This molecule plays crucial roles in providing energy use and storage in the body. After a meal, glucose is released into the blood, which is then channelled by insulin into the various organs where it is needed as fuel. This may sound familiar from high-school biology lessons, namely from the infamous ‘mitochondria are the powerhouse of the cell’. Glucose provides the fuel for mitochondrial metabolism, which in turn keeps the whole body, from tiny cells to whole systems, up and running. When the body has enough glucose to keep everything running smoothly, it can store excess glucose in the form of glycogen, more highly branched chains of glucose, to be used in case of a low glucose emergency. And when the body has enough glycogen, it uses the leftover glucose to make fat, for even longer-term storage. In this series of metabolic processes, glucose is used as efficiently as possible, great if you don’t have an ample supply, not great if you are just a few steps away from cookies in the office.

From Sugar High to Energy Crash

All this science is fascinating, of course, but what does this all mean practically? When we eat a high sugar meal, be it by having sweet starch-dense foods such as a nice slice of cake, glucose is quickly released into the blood, resulting in a glucose peak. As insulin channels the glucose out of the blood, this results in a glucose crash. This rollercoaster of excess to deficit brings about several symptoms: tiredness, brain-fog, light-headedness, and crucially, a hunger to regulate your blood-sugar levels. It is estimated that after a glucose crash people tend to eat 80 kcal more in their next meal, making healthy dietary choices more difficult.

How can we avoid glucose peaks and crashes? A complete diet, which includes fibres, fats and proteins, helps modulate glucose uptake. As your body works to digest these macronutrients, less glucose is quickly released into the blood. And if we take a closer look at fibres, we see that these are also sugars! But arranged in complex forms, making them harder or slower to digest, ensuring a slow release of sugar over time. This results in a more modulated source of fuel, rather than peaks and crashes. These fibres also provide fuel for our gut bacteria and may play an important role in maintaining a healthy immune system.

While glucose has been key to human evolutionary success, our extremely efficient bodies are struggling to adapt to an abundance of sugar in our daily lives. Understanding the science behind sugar metabolism, such as the closer look we took here at glucose, helps us make healthier food choices, and inspires innovation in the lab. At CarbExplore, we study glucose peaks with the use of in-vitro models, which are crucial for the discovery and development of slowly digestible carbohydrates. Armed with science, we can develop healthier ingredients and formulations to benefit our efficient glucose machines.