Fruit Fructose vs. Added Sugar: What You Need to Know for Your Diet

Let’s thoroughly explore the topic of ‘fructose’ found in fruits, which are celebrated for their natural and healthy qualities.

When dieting, the first food that comes to mind to avoid is carbohydrates. Of course, carbohydrates are not bad, but the sugars within them can be said to be the leading cause of weight gain.

But fruits are also incredibly sweet, so does the fructose in fruit also cause weight gain? Can it be bad for the body if it’s a natural food?

Let’s first understand sugar. Sugars, found in carbohydrates and blamed as the main culprit for weight gain, are essentially ‘sweet substances’ found in sugar or honey, etc. These sugars can be further divided into smaller units called ‘saccharides,’ divided into monosaccharides with one sugar molecule and disaccharides with two. Here, fructose and glucose belong to monosaccharides, and sucrose (table sugar), a combination of fructose and glucose, falls under disaccharides.

But fructose, a sugar in fruit, has some differences from other sugars. First of all, it is much sweeter than other sugars. According to Scott Helstad’s 2019 book, fructose feels 1.5 to 1.7 times sweeter than regular table sugar. In everyday life, honey, which has a higher ratio of fructose and glucose floating separately than disaccharide sugar, feels about 25% sweeter.

Also, the process of metabolizing in the body is different. The general understanding of sugar metabolism is that it secretes insulin from the blood vessels, breaks it down, and moves it into cells, but this is the metabolism process of glucose. Most of the fructose is broken down in the liver, some into glucose, some into fat, and some used as an energy source. Thus, it hardly raises blood sugar because fructose is absorbed and broken down in the liver, not the blood vessels.

In addition, when fructose is consumed, insulin secretion is minimal. According to a 2005 study from the University of Toronto, fructose hardly stimulates cells that secrete insulin compared to glucose, which significantly stimulates insulin secretion.

If you only look at these characteristics, fructose seems like a healthy sugar that doesn’t cause weight gain. However, it is said that avoiding such fructose when dieting is good.

A 2009 study from the University of California, Davis, described that fructose can cause blood lipid problems. In particular, it can increase VLDL cholesterol, cause visceral fat, and trigger heart disease. Looking at a 2006 study from the University of Florida it is written that fructose can increase uric acid, causing hypertension and gout. Not only this, but fructose, which is directly absorbed into the liver, can cause non-alcoholic fatty liver disease, and it cannot suppress appetite as much as glucose, which can lead to overeating and obesity, according to other studies.

From this, it is clear that fructose, like additives, should be avoided as it can hurt the body when consumed in large amounts. So, what about fruits containing fructose?

If you only look at fruits, eating them in moderation is not a big problem, even during a diet. After all, fruits are made of fructose and contain a lot of water and dietary fiber. Dietary fiber is a food optimized for dieting as it absorbs calories close to 0, has a high feeling of fullness, and lowers blood sugar. Also, fruits are rich in various vitamins, minerals, and antioxidants, so it’s okay to consume them in a diet, as long as you don’t overeat, like eating a whole box of tangerines.

It would be better to be cautious of artificial fructose added to processed foods, predominantly liquid fructose found in snacks and beverages, rather than fruits.

By. Soo Jung Shin