The tiny diet tweaks that will change your life

What you eat, the food combinations you make and when you exercise all play an essential role in keeping you healthy. This is how it works.

Glucose is our body’s preferred energy source. Each cell uses it to perform actions: our eye cells to see, our heart cells to contract, our brain cells to think.

We get glucose from the food we eat (from starches and sugars, which break down into glucose).

Our body thrives when the amount of glucose it receives is equal to the amount of glucose it needs for energy. But, too much glucose is harmful.

If we eat a meal that releases too much glucose too quickly to our body, that’s called experiencing a glucose spike.

Glucose spikes overwhelm our cells, causing inflammation, accelerated ageing, cravings, energy swings, and more. Glucose spikes slowly increase the overall amount of glucose in our body.

This leads to long-term consequences, such as type 2 diabetes or infertility.

Turns out, 90 per cent of us experience glucose spikes every day, without knowing. And we suffer the consequences. So here are some tips to avoid spikes, reverse your symptoms, and feel amazing.

Too much glucose in your diet is harmful.

AFTER YOU EAT, MOVE

There are multiple traditions that recommend walking after eating and they exist for good reason.

As soon as the influx of glucose (from a large bowl of rice, for example) hits our body, two things can happen.

If we stay sedentary as the spike reaches its peak, glucose floods our cells and overwhelms our mitochondria (the powerhouses that are responsible for turning glucose into energy). Potentially dangerous molecules are produced, inflammation increases and excess glucose is stored away in the liver, muscles and fat.

If, on the other hand, we contract our muscles as the glucose moves from our intestine to our bloodstream, our mitochondria have a higher burning capacity. They aren’t overwhelmed as quickly – they are thrilled to use the extra glucose to make energy to fuel our working muscles. On a continuous glucose monitor graph, the difference is stark.

A large 2018 research review looked at 135 people with type 2 diabetes and found that aerobic exercise (walking) after eating decreased their glucose spike by between 3 and 27 per cent.

If you want to hit the gym after meals, that’s going to help even more – although some people find strenuous exercise on a full stomach quite hard. The good news is, you can work out at any time up to 70 minutes after the end of your meal to curb a glucose spike; 70 minutes is around the time when that spike reaches its peak, so using your muscles before that is ideal. You can also use your muscles acutely in a push-up, a squat, a plank, or any weight-lifting exercise.

Resistance exercise (weight-lifting) has been shown to decrease the glucose spike by up to 30 per cent and the size of further spikes over the following 24 hours by 35 per cent.

It’s rare that you’ll be able to curb the entire glucose spike, but you can make a sizeable dent in it.

Move after you eat.

Try this: Rate how you feel when you have a sweet snack and stay sitting. Rate how you feel if you eat the same snack and then walk for 20 minutes afterwards. How’s your energy and how are your hunger levels in the next few hours?

FLATTEN YOUR BREAKFAST CURVE

In 2018, a study done at Stanford University in California set out to test the commonly accepted belief that, unless you have diabetes, your glucose levels should be of no concern. Second, and perhaps more controversially, they wanted to test a practice that has become a cultural norm: that cereal for breakfast is good for you.

Twenty participants were recruited, both men and women. None of them had been diagnosed with type 2 diabetes: their fasting glucose (as measured once a year by their doctor) was in the normal range. The experiment consisted of eating a bowl of cornflakes with milk while wearing a continuous glucose monitor.

The results of this study were alarming. In those healthy individuals, a bowl of cereal sent their glucose levels into a zone of deregulation thought to be attainable only by people with diabetes. Sixteen of the 20 participants experienced a glucose spike above 7.8 mmol/L (the cut-off for prediabetes, signalling problems with glucose regulation), and some even spiked above 11.0 mmol/L (in the range of type 2 diabetes).

That didn’t mean that the participants had diabetes – they didn’t. But it did mean that people without diabetes could spike as high as those with diabetes and suffer the harmful side effects those spikes cause. The discovery was groundbreaking.

Avoid an early morning spike.

The fact that a bowl of cereal causes spikes makes empirical sense. Cereal is made of either refined corn or refined wheat kernels, superheated, then rolled flat or puffed into shape. It’s pure starch, with no fibre left. And because starch is not the most palatable thing on its own, table sugar (sucrose, made of glucose and fructose) is added to the concoction. Vitamins and minerals join the mix, but the benefit of these doesn’t outweigh any of the harm of the other components.

Because of the way we eat today, early-morning spikes seem to be the norm.

Whether it’s cereal, toast and jam, croissants, granola, pastries, sweet oats, biscuits, fruit juice, Pop-Tarts, fruit smoothies, acai bowls, or banana bread, the typical breakfast in Western countries is composed of mostly sugar and starch – a ton of glucose and fructose.

A breakfast that creates a big glucose spike will make us hungry again sooner. What’s more, that breakfast will deregulate our glucose levels for the rest of the day, so our lunch and dinner will also create big spikes.

This is why a spiky breakfast is a one-way ticket to the glucose rollercoaster. A flat breakfast, on the other hand, will make our lunch and dinner steadier.

On top of that, first thing in the morning, when we are in our fasted state, our bodies are the most sensitive to glucose. Our sink (or stomach) is empty, so anything that lands in it will be digested extremely quickly. That’s why eating sugars and starches at breakfast often leads to the biggest spike of the day.

The best thing you can do to flatten your glucose curves is to eat a savoury breakfast.

An ideal breakfast for steady glucose levels contains a good amount of protein, fibre, fat and optional starch and fruit (ideally, eaten last). If you’re buying breakfast at a coffee shop, get avocado on toast, an egg muffin, or a ham and cheese sandwich, not a chocolate croissant or toast and jam.

This is an edited extract from Glucose Revolution: The life-changing power of balancing your blood sugar level by biochemist Jessie Inchauspé, Penguin Random House Australia, out March 29

Originally published as The tiny diet tweaks that will change your life