Healthy Life

The term “sugar rush” is usually associated with children who’ve become overexcited after indulging in one treat too many.

But consuming too much sugar over time has an adverse and potentially dangerous effect on people of all ages.

Know your different saccharides (sugars)

Did you know that there are various kinds of sugar? Dr Elmo Pretorius, a specialist physician and endocrinologist at Mediclinic Vergelegen, explains that the term "sugar" refers to a group of molecules that we perceive as sweet because of the taste receptors on our tongues.

These molecules can exist in different forms. For instance, they can be single molecules called monosaccharides, like glucose. Alternatively, glucose can combine with another molecule, such as fructose, forming a disaccharide. When these molecules link together in a chain, they become polysaccharides, which are known as starches at this point. Sugars are present in various foods, ranging from milk to fruits, and they all serve as sources of energy.

Low GI vs high GI

On the one hand, the fact that sugars provide energy is a good thing, especially since glucose is the only form of energy that the brain can use. But, says Dr Pretorius, it’s vital to understand that not all sugars are created equal. “All sugars are broken down by your digestive system and released into the bloodstream, but the simpler the sugar, the more quickly it is released,” he explains. Foods that are complex and require some time and energy to break down are known as low glycaemic index (GI) foods, while those that release energy as soon as they hit the digestive tract are called high GI foods – and it’s the latter that create health issues.

“Your body doesn’t want high levels of glucose circulating,” Dr Pretorius says. To regulate glucose levels and ensure they remain constant, the pancreas secretes insulin. “The pancreas starts working as soon as you eat sugar. It produces insulin, which acts like a key, unlocking cells, which then open to accept the glucose.” The cells most affected are those in fatty tissue as well as in your liver – and that’s where the problems start. Besides storing fat, your fat tissues also store excess glucose. So, if you eat a lot of sugary foods over time, you’re certain to gain weight. This may eventually lead to obesity.

On the other hand, when your liver stores too much sugar, it may become fatty, a condition that can lead to cirrhosis, liver failure, or liver cancer. An added problem is that because people often feel hungry again shortly after eating high GI foods, a vicious cycle is set in place.

The danger of insulin resistance

That’s not the only harmful cycle that can develop, says Dr Pretorius. Eating a high-sugar diet can lead to insulin resistance, as the cells in fatty tissue and liver try to protect themselves by “ignoring” the insulin’s message to take up glucose. Your pancreas then reacts by producing even more insulin, causing insulin to accumulate in your bloodstream. This places strain on the pancreas and can lead to the development of diabetes.

It’s a long-term process, however, so if your pancreas is healthy, your body can handle the occasional sugary snack. But what about that sugar rush? “What we call a ‘sugar rush’ doesn’t refer to glucose, which insulin helps our bodies to absorb almost immediately,” explains Dr Pretorius. “Rather, you’re feeling the results of insulin, which the pancreas sometimes releases in excessive amounts. This leads to low glucose.” That’s the reason you may feel a little shaky after a sugary drink or feel a hunger pang shortly after eating something sweet.

Reduce your risk of lifestyle-related diseases

Dr Pretorius says people who eat large amounts of sugar are at risk for lifestyle diseases like hypertension, diabetes, metabolic syndrome, coronary artery disease and gout. However, it’s still unclear whether sugar directly causes these issues, or whether people with high-sugar diets are generally less likely to exercise or consume enough other healthy foods.

  • Consume low GI carbs rather than their high GI counterparts.
  • Vary your diet as much as possible – eat enough protein, fibre and micronutrients, like vitamins and minerals.
  • Try to eat food that’s as close to nature as possible – avoid processed foods, as well as those that are overcooked.
  • Choose a plant-based diet as far as possible – plant-based foods are high in fibre, better for your gut, and keep you full for longer.

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