DR MICHAEL MOSLEY: Does fructose cause your love handles?

With the arrival of winter days, I feel an insane urge to eat sugary, carb-heavy comfort food.

This is obviously due to the days getting colder and shorter and me craving sugar to cheer me up, but it could also be due to a subconscious fear of running out of calories in the winter months.

Despite all the temptations leading up to Christmas, I try to keep my sweet holiday indulgence to a minimum, knowing it’s the road to a growing waistline and type 2 diabetes. Additionally, there is mounting evidence to support a new theory that a certain sugar component is a key factor in our obesity crisis.

The idea that excess sugar can lead to weight gain is not new. But the stuff we call “table sugar”—the sweet white or brown stuff in your cupboard—is actually made up of two sugars: glucose and fructose.

Unless made with artificial sweeteners, most cakes, cookies and soft drinks you buy in the UK contain equal amounts of glucose and fructose (in contrast, the chances of you finding either these foods or fructose are much higher in the US is). The drink is sweetened with high fructose corn syrup, which, as the name suggests, tends to contain more fructose than glucose.

Fructose has long been considered a “healthy” sugar. But it turns out that when consumed in large quantities, it can have a dark side

Fructose has long been considered a “healthy” sugar. This is because it is the main sugar in fruit and does not raise your blood sugar levels to the same extent as glucose. And that is why people with diabetes are sometimes advised to switch to fructose as a sweetener.

However, it appears that fructose, at least when consumed in large quantities, may have a dark side.

So say scientists from the Anschutz School of Medicine at the University of Colorado in the USA in an article published in the journal Obesity.

Based on their previous research on the effects of fructose on cells, they claim that, unlike other sugars, fructose causes our metabolism to go into an “energy saving mode”. This then leads to hunger and causes us to lose control of our appetite, causing us to eat more (not just sweet food) even though we have eaten enough.

Normally, your food is broken down and absorbed in the intestines and then converted into adenosine triphosphate (ATP) – a substance that every cell in your body uses as its main source of energy.

However, scientists at the University of Colorado claim that consuming too much fructose suppresses ATP production. And when ATP levels begin to drop, your brain, fearing that its energy supply is at risk, activates hunger signals and tells you to eat more. what you do

But because you are now eating much more than your body needs, you are getting fatter.

Further evidence that fructose may play an important role in obesity comes from previous research published in the prestigious journal Nature in 2019. In this study, researchers at NewYork-Presbyterian/Weill Cornell Medical Center divided mice into three groups: one group was given a low-fat diet; the second on a high-fat diet; and third, a high-fat diet with added fructose.

The mice fed a fructose diet ate much more fat, even though they consumed the same number of calories as the other groups. This was because their villi – the tiny finger-like projections that line the small intestine (in mice and humans) and help your body absorb the calories you take in – grew much longer.

The scientists suspected that the longer villi caused the mice’s bodies to absorb many more calories, causing them to gain fat.

Previous studies by the same team also showed that feeding fructose to mice stimulates the growth of other cells and increases the risk of colon cancer.

When asked why consuming fructose had these effects, the scientists suggested that it might have been a winter survival strategy.

Before widespread and mass-produced food existed, fruit was the primary source of fructose in nature. And most fruits become sweet and ripe in late summer and fall.

So from an evolutionary perspective, it makes sense that eating fructose (in the form of fruit) not only helps you get more energy to lie down while your body tries to prepare you for the long winter months when food is scarce. It registers as fat, but it also helps shut down your cells (putting them in “power saving mode”) so they use less fuel.

What to keep in mind the next time you’re craving something sweet: It’s the fructose that makes you want more.

But while this can be a useful survival strategy when you’re a hibernating animal like a bear, in modern times, whenever we feel the slightest pang of hunger, we can buy a pack of cookies or order a takeaway useful to all. .

The researchers involved in the Nature study were careful to emphasize that the problem does not stem from eating high-fructose fruit, as it contains fiber (which is not only good for the gut, but also reduces sugar spikes ) and other valuable plants. Links; It comes from the added sugars we consume every day.

Like Dr. As Marcus DaSilva Goncalves, an endocrinologist who led the study, put it: “Fructose is almost ubiquitous in the modern diet, whether from high fructose corn syrup, table sugar, or from natural foods such as fruit.” “Fructose itself is not harmful, it is a problem of overconsumption.”

Next time you’re tempted by a sweet treat, remember: it’s the fructose that makes you eat more.