Fructose: Could It Be Worse For You Than Alcohol?

It is well-documented that obesity is increasing to epidemic proportions around the world, and particularly in Australia.  The major reasons for this obesity epidemic continue to be debated, but it is undeniable that physical inactivity and poor dietary habits are at the forefront of this alarming trend.

For most of us, losing weight is a tough process that takes more than just diet and exercise to be successful. There are many factors that influence weight loss, including stress and sleep, but the chemical composition of our food is an aspect that is often forgotten. After reading an article titled “Toxic Sugar” in the science magazine Cosmos, I wanted to share the knowledge that this article provides. With weight loss being so hard for many, this “one percenter” of information could be the extra help you’re looking for to keep you on track with your weight loss goals.

The Cosmos article states that, previously, the most common cause of liver disease in the US was alcohol abuse, with liver biopsies highlighting regions of dead cells, inflammation, and fatty changes. However, these changes to the liver are now being observed in non-alcoholics. It is argued that the reason for such damage to the liver is coming from an over consumption of sugar, and in particular, fructose.

Fructose is a simple sugar found in many plants and is absorbed directly into the bloodstream. Fructose is very sweet and is found in honey, tree and vine fruits, flowers, berries, and most root vegetables. Commercially, fructose is derived from sugar cane, and is added to foods and drinks to enhance their palatability and taste.

Natural sources of fructose include fruits, vegetables, and honey.  Commercial sources of fructose include granulated sugar, brown sugar, high fructose corn syrup, honey, maple syrup, molasses, and corn syrup.  Foods high in fructose include soft drinks, apple sauce, honey, juice, salad dressing, and fruit.

A major source of fructose in our diet comes from high-fructose corn syrup, which is a sweetener made from maize and is widely used in soft drinks. Fructose is widely used in the processed food industry, which is underlined by this frightening observation from Professor O’Dea from the University of South Australia: producers “add sugar because it sells more”.

Why is that fructose in our diets can cause so much harm?  Dr Robert Lustig, an endocrinologist in California, believes that fructose causes an increase in insulin resistance, a fatty liver, and increases the risk of type 2 diabetes. The signs of type 2 diabetes and insulin resistance include an increased waist circumference, high blood sugar levels, and high cholesterol levels, which can lead to cardiovascular disease and even stroke. Lustig explains that fructose is different to glucose, in that glucose can be taken up by any body tissue, whereas fructose is predominantly taken up by the liver.  Fructose is also processed differently in the body, and has been shown to lead to increases in blood pressure and insulin resistance.  In addition, fructose is more likely to be converted to fat.

The Cosmos article also highlights how high levels of fructose in the diet are associated with a fatty liver, promoting fat storage around the heart, pancreas, and liver. Fructose also has little impact on the hormones that control our hunger: leptin and insulin. As a result, our body’s mechanisms for telling us when we are full are not activated with over-consumption of high fructose foods.

Many of us also have a “sweet tooth” which doesn’t help our cause when we are trying to avoid excess consumption of sugar. Nicole Avena, a researcher into sugar addiction at the University of Florida, says that the stimulation of sweetness on the tongue brings feelings of enjoyment. Receptors on the tongue are wired to our brain’s “reward” circuit, making particular experiences enjoyable. From an evolutionary perspective, it is contended that sugary foods, due to their high calorie levels, would have been a valuable energy source to our ancestors, so we have evolved to crave sugar as a result. Now that sugar is readily available, that craving is creating many problems such as the rapid rise in obesity and diabetes rates worldwide.

In addition to a balanced, nutritious diet and regular exercise, one simple act that can aid your weight loss and help to prevent type 2 diabetes is to avoid over-consuming fructose. This can be achieved by avoiding commercial foods high in artificial sweeteners (such as soft drinks, fruit juices, and sauces). Avoiding the over-consumption of fruit will also lower your intake of fructose. The current dietary guidelines state that 2 serves of fruit per day are sufficient for health benefits.  Therefore, it is important to limit yourself to 2 serves of fruit per day and avoid artificially sweetened foods. This will not only help your weight loss goals but also decrease your risk of liver disease, type 2 diabetes, and other obesity-related conditions.

(Image sources: The Kitchn, Los Angeles Times,