Blood sugar spikes are not necessarily bad for you

It's trendy to be concerned about blood sugar spikes, but these can be a normal response to eating. Here's when you don't need to worry.

Over the last few years, two surprising things have started happening.

Normal, otherwise healthy people have started wearing devices that allow them to check their blood sugar levels throughout the day. Others have been cutting out refined carbohydrates such as white bread and pasta entirely.   

In fact, authors, podcasters and wellness influencers have been selling the idea that we all need to check for blood sugar spikes and avoid them. According to this extreme view, we allow significant amounts of glucose in the bloodstream at our peril. Even in healthy people with no metabolic diseases, to risk a blood sugar spike is, they say, to welcome hormonal imbalances, acne, mood swings, and worse.   

But now experts are pushing back. Here's when to worry, and when that carbohydrate-heavy meal is unlikely to do any lasting damage.

Why does our blood sugar spike?

When we eat and digest sugary foods, such as refined sugar, fruit and carbohydrate-rich food, our blood sugar naturally inclines.

That's because as we digest carbohydrates and sugars, they are broken down into glucose, which is then absorbed into the bloodstream, temporarily leading our blood sugar levels to rise. As it does so, the pancreas responds by secreting the hormone insulin, which helps move the glucose out of our bloodstream and into the body's cells to provide energy. 

It's not only food that can raise our blood glucose levels. During high-intensity exercise, hormones such as adrenaline signal the liver to release more glucose into the bloodstream, providing extra fuel for working muscles. As a result, blood glucose can temporarily rise, says Jennifer Sherr, a paediatric endocrinologist from Yale School of Medicine, Connecticut in the US.

In people with diabetes the body does not produce enough insulin, or it no longer works as it should (insulin resistance). This means that after eating, their blood sugar can become dangerously high. In this case, it's essential that people carefully manage their diet, exercise, and monitor their blood sugar levels to avoid spikes. Some people also need to take medications such as insulin or metformin.

Glucose spikes are normal

Among healthy individuals, a rise in blood glucose after eating is a normal physiological response. "The biggest misconception is that every glucose spike is harmful," says Adrian Brown, associate professor in nutrition and dietetics from University College London in the UK. 

Recently I experimented with giving up added sugar for six weeks (read more from the BBC on what I learned). Since then, I've been especially attuned to the fact that when I eat sugary foods, my blood sugar is bound to rise. 

Our blood sugar level typically peaks around one hour after eating and tends to return to baseline within the next two hours. If a spike is brief and occurs in someone with a normal........

© BBC